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How Would You Rate Them?

FitSugar — Wed, 20 Jun 2007 15:15:00 -0700

We all had a good time reorganizing InTouch's list of the top ten hottest females on the beach and now they've gone and ranked the men. Here are the lucky men they picked (in no particular order):

Andy Baldwin
David Beckham
David Charvet
Josh Duhamel
Zac Efron
Hugh Jackman
Nick Lachey
Mario Lopez
Matthew McConaughey
John Mayer

Rate them in order from best to worst (one being your favorite body, ten being your least favorite) beach body in the comments section below.

To see how InTouch ranked 'em, read more

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All Kinds of Gifts For Bikers

FitSugar — Mon, 16 Nov 2009 10:00:32 -0800

Nothing beats heading out for a ride on Christmas day decked out in new gear with all sorts of new biking accessories. From full fingered, padded cycling gloves - a wintertime must have - to entry level biking computers, this list has something every cyclist wants. If your biking friend has everything, splurge and give them a biking computer with a built in heart rate monitor for the full fitness riding experience. Fancy cycling knickers are a perfect gift too. Even if there is snow on the ground, these padded knickers will be great for early Spring rides after the thaw. Don't forget the urban cyclist either. I have found a great set of panniers and a super cute bike basket as well. Take a gander at the gifts and tell me what cycling gear you covet for Christmas.

Grade Your Hikes

FitSugar — Thu, 12 Nov 2009 08:00:00 -0800

I love hiking in the Fall because of the beautiful scenery and perfect weather - the crisp air never leaves me too hot or too cold. On the weekends I often go on all-day or multi-day hikes in Yosemite valley or the Lake Tahoe region. Some of my friends equate hiking with a leisurely stroll through the woods, but anyone who hikes regularly knows this isn't always the case. Whether it's steep, rocky, or exposed terrain, a hiking trail can be quite difficult.

One way I prepare for an all-day hike is by researching the difficulty of the trail I'm walking. I'll use guidebooks and the Internet as resources, as well as the Yosemite Decimal System (YDS). The YDS is a three-part classification system that rates the difficulty of walks, hikes, and rock climbs based on categories of terrain, length, and level of danger. Not all routes are graded in each category - generally speaking, rock climbs are the only routes that use all three grading systems of the YDS.

To learn how hikes are classified, read more.

Classifying a route's terrain is what's most applicable to hiking trails, especially longer, more intense hikes such as the John Muir trail or Half Dome hike. Here's a general breakdown of the different terrain class types found in the YDS:

Class 1: Walking on a relatively flat trail with little chance of injury. Many backpackers compare a class 1 route to walking on a sidewalk.
Class 2: A simple trail that might have a slight incline. You may have to use your hands to balance while scrambling up rocks.
Class 3: You'll definitely need to use your hands and feet to find balance along parts of the trail while scrambling up rocks. There may be exposed terrain during the hike, though a fall should not prove fatal.
Class 4: This hike will involve climbing up steep terrain, and even though the route will have some natural protection, a fall could prove fatal.
Class 5+: Reserved for rock and aid climbing. Protection and gear recommended for these climbs as a fall will prove fatal.

Keep in mind that the YDS is a somewhat subjective grading system and there can definitely be some overlap and debate over a class assignment. I continue to use it as a guide because I can search for harder or easier trails depending on my mood that day. I'm also finding that more and more backpackers are using the YDS lingo when describing a trail to one another.

You can also keep a journal with details of your favorite trails and try rating them for yourself. If you do assign a class rating to a trail, the class assignment should reflect the hardest part of the hike. (For example, if you went on a hike that was mainly class 1 but had a few elements of a class 3 route, classify the hike as a class 3 route.)

Tell me, what class of hikes do you usually stick to?

Speak Up: How Would You Rate Them?

FitSugar — Wed, 06 Jun 2007 00:00:00 -0700

InTouch recently rated the hottest beach bodies from our favorite starlets, but I have realized that you guys are not always in agreement with how the glossies rate celebrity beach bodies. So I am wondering what order you would put them in, here are the ten women (in no particular order):

Cameron Diaz
Denise Richards
Drew Barrymore
Jessica Biel
Jessica Alba
Kate Bosworth
Kate Hudson
Michelle Rodriguez
Tyra Banks
Vanessa Minnillo

Rate them in order from best to worst (one being your favorite body, ten being your least favorite) beach body in the comments section below. To see how InTouch ranked 'em, read more

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The Lowdown on Exercising High

FitSugar — Mon, 26 Oct 2009 09:00:00 -0700

Recently FitSugar reader mamasitamalita wrote in to ask about her friend who works out while buzzed. Apparently it's more common than I thought, and it's not the only thing people are doing before hitting the gym. An anonymous reader commented

"Sometimes, every once in a while, I will get stoned before yoga or a long run - it helps me to calm down and focus on the task at hand, rather than obsessing about work or personal stresses."

So this brings up another issue. What about working out while high? Although illegal, people still smoke pot, so to find out if it's safe to light up before burning calories keep reading

Health Food Headlines

FitSugar — Thu, 08 Oct 2009 03:00:44 -0700

I love food. Not just eating it, but reading about it too. Here are three food-driven headlines that caught my eye.

Calorie Postings Don’t Change Habits, Study Finds - New York Times
Remember all the controversy about chain restaurants in the Big Apple being forced to post calorie counts? Well, it looks like you can post the calories, but consumers will consume what they want. A study performed in NYC neighborhoods where obesity rates are high found that although folks said the calorie counts helped them make healthier food choices, they actually ordered higher calorie items than before the calorie counts were posted.

10 Foods Most Likely to Make You Sick - Web MD
Oh, the irony. The Center For Science in the Public Interest researched food-borne illnesses and found that some health foods topped the list, including eggs, tomatoes, and sprouts.

Starting Good Food Habits in Kids From the Womb - Time
As a baby is being formed in utero, so is its sense of taste. A fetus in the second and third trimester has a highly sensitive palate, and what the mother eats helps determine the child's early flavors of choice. All the more reason to eat a variety of foods when pregnant and nursing.

Yoga With Biggest Loser Trainer Bob Harper

FitSugar — Thu, 24 Sep 2009 03:47:23 -0700

I gaze out past the middle finger of my left hand into the Hollywood Hills as my right quad quivers holding Warrior 2. This is when Bob Harper, trainer from The Biggest Loser, says, "You might be feeling a bit of heat in your thigh right about now." He's teaching a yoga class to a few bloggers and ladies of the press, and we all laugh as our legs burn.

You can hear Bob's charming smile even in his calm instructions leading us from pose to pose. He's a thoughtful teacher, with smart sensitive hands that gently mold you into correct positions. I've had a bit of a TV crush on him for years, and now after meeting him in person, I'm smitten. This yoga class and round table discussion were produced by Go With the Grain, and although carbs did come up (as well as protein, which Bob thinks is overrated), we mostly talked about the show, yoga, and a dash of musical theater. He mentioned the contestant Shay more than a few times; she was clearly on his mind. Having lived through each moment during filming, Bob doesn't watch the show but checks the ratings the following morning. He's also learned to avoid the online community boards: "They're so mean." He addresses the recent criticism about all the screaming on the show and shakes his head in dismay and bemusement about the clip of a tirade used on the Emmys.

Bob said there is so much of the action at the ranch that ends on the cutting room floor because it doesn't make for good TV. Which brings us to yoga. Quiet, slow yoga. He actually does a fair bit with his contestants because it's meditative. "It helps them own their bodies," he explains. Working with people that weigh over 300 pounds, Bob gets creative with props, using benches to help support Shay in Chaturanga. Ten minutes of sun salutations is often part of the exercise homework he gives his team.

To see if Bob and Jillian, his rival trainer on the show, are buddies, just read more.

Bob still teaches a Saturday spin class at a Crunch in LA and has participated in the SF to LA AIDS ride, so I asked him if he rides a road bike much. "I spin four to five days a week and get my cycle time there. Mostly, I like to ride my motorcycle." Who taught him to ride? Jillian. They hang out all the time. Cute.

As a personal trainer, we know Bob is into fitness, but food is a major part of the health picture. Growing up on a cattle farm, with "two coffin freezers full of meat," Bob is not into animal protein and believes in a plant-based diet. He feels too much emphasis has been placed on protein. He really wants people to focus on fruits and veggies, and of course grains. On the show, he tell contestants that life on the ranch is the little picture. It's extreme. Going forward with their lives after The Biggest Loser they're going to need to find balance. Which is what we all need, especially when doing the standing splits to end a series of standing poses he taught in his class.

Obviously, I am big fan of Bob's - are you? How was your last yoga class? Ever taken one with a celebrity yogi? Share the details in my Yoga Stretch and Tell group.

Gear Review: Kahuna Long Board With Big Stick

FitSugar — Fri, 11 Sep 2009 09:00:46 -0700

If you are looking to keep the surf of Summer alive in your landlocked life, you might want to try a dry version of stand-up paddling (SUP). Riding a long skateboard by Kahuna Creations while paddling yourself about with a Big Stick is the skating version of the popular water sport. As you can see, Matthew McConaughey is a fan of skate paddling; I would say I am too, but I'm not quite proficient enough at stopping yet to really claim to be a fan.

The Kahuna boards are beautiful - I tried the 45-inch Haka Pua ($169) - as are the Big Sticks ($89). To see how it feels to use them, just read more.

I had fun paddling up and down my street. Not only is it an upper body workout, but the motion gets your heart rate up too. As someone who is accident-prone with no prior skateboarding experience, it just doesn't feel all that safe - hence the helmet. Falling into water while SUPing is much less daunting than wiping out on asphalt. I found stopping and steering difficult, but feel these skills would come with practice. And skate paddling is fun, so practicing to gain skills would be a good time.

Here are a few more detailed shots of the board and stick.

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Check out this video clip of two dudes who know how to work the Big Stick.

Infertility in men

FitSugar — Wed, 08 Oct 2008 17:35:50 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

New At-Home Fertility Test Kit

Fertell, the first at-home fertility test kit, became commercially available in June 2007. The Fertell kit contains tests to screen for both male and female infertility. Men can test their semen for concentrations of motile sperm, while women can test their urine for levels of follicle-stimulating hormone (a marker for egg quality). Results are available in fewer than 90 minutes and, according to the test kit's manufacturer, are 95% accurate. However, Fertell does not screen for all types of infertility problems and should not be used as a replacement for a complete evaluation by a doctor.

Intracytoplasmic Sperm Injection May Be Overused

Use of intracytoplasmic sperm injection (ICSI), in combination with in vitro fertilization (IVF), has increased 5-fold over the past decade, even though the proportion of men treated for male infertility has remained the same. This increase suggests that doctors are now using ICSI to treat problems other than male infertility, according to a 2007 study in the New England Journal of Medicine. Some doctors recommend ICSI for women who have failed IVF cycles or who have few or poor-quality eggs. According to the Society for Assisted Reproductive Technology, there is little evidence that ICSI can help couples conceive when male infertility is not a factor.

Infertility and Birth Defects

Although there has been concern that assisted reproductive technologies (ART) may increase the risk for birth defects, infertility itself may be a risk factor, regardless of whether ART is used. Even children born to infertile couples who do not use ART have a slightly increased risk for birth defects, indicates a 2006 study in the British Medical Journal.

Varicocele Embolization

Varicocele embolization, a minimally invasive surgical approach to varicocele repair, can help improve sperm count and motility, according to research presented at the 2006 annual meeting of the Radiological Society of North America. Varicoceles (varicose veins in the testicles) are often linked to male infertility.

Introduction

Infertility is the failure of a couple to become pregnant after one year of regular, unprotected intercourse. In both men and women the fertility process is complex. Even under ideal circumstances, the probability that a woman will get pregnant during a single menstrual cycle is only about 30%. And, when conception does occur, only 50 - 60% of pregnancies advance beyond week 20. In many cases, infertility is caused by a combination of problems in both partners that conspire to prevent conception from occurring.

About 8 - 10% of couples of reproductive age experience infertility, and in around 40% of these cases male infertility is the major factor. Another 40% of infertility problems are caused by abnormalities of the woman's reproductive system, and the remaining 20% involve couples who both suffer reproductive difficulties.

Infertility affects one in 25 American men. More than 90% of male infertility cases are due to low sperm counts, poor sperm quality, or both. Whether sperm counts are declining overall in industrialized countries is a controversial issue. However, over the last few years the number of assisted reproductive procedures that target male infertility have increased, while female procedures have declined.

The male reproductive system creates sperm that is manufactured in the seminiferous tubules within each testicle. The head of the sperm contains the DNA, which when combined with the egg's DNA, will create a new individual. The tip of the sperm head is the portion called the acrosome, which enables the sperm to penetrate the egg. The midpiece contains the mitochondria which supplies the energy the tail needs to move. The tail moves with whip-like movements back and forth to propel the sperm towards the egg. The sperm have to reach the uterus and the fallopian tube in order to fertilize a woman's egg.

Male Reproductive System

Male fertility depends on the proper function of a complex system of organs and hormones:

The process begins in the area of the brain called the hypothalamus-pituitary axis, a system of glands, hormones, and chemical messengers called neurotransmitters, all of which are critical for reproduction.
The first step in fertility is the production of gonadotropin-releasing hormone (GnRH) in the hypothalamus, which prompts the pituitary gland to manufacture follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
FSH maintains sperm production, and LH stimulates the production of the male hormone testosterone.
Both sperm and testosterone production occurs in the two testicles, or testes, which are contained in the scrotal sac (the scrotum). (This sac develops on the outside of the body because normal body temperature is too high to allow sperm production.)

The male reproductive structures include the penis, the scrotum, the seminal vesicles, and the prostate.

Sperm are manufactured in several hundred microscopic tubes, known as seminiferous tubules, which make-up most of the testicles.

Surrounding these tubules are clumps of tissue containing so-called Leydig cells. Here, testosterone is manufactured.

Sperm Development. The life cycle of sperm consists of a remarkable journey that depends on hormonal signals combined with a mechanical process. It takes about 74 days:

Sperm begin partially embedded in nurturing amoebae-like cells known as Sertoli cells, which are located in the lower parts of the seminiferous tubules.
As they mature and move along, they are stored in the upper part of the tubules. Young sperm cells are known as spermatids.
When the sperm has completed the development of its head and tail, it is released from the cell into the epididymis. This remarkable C-shaped tube is 1/300 of an inch in diameter and about 20 feet long. It loops back and forth on itself within a space that is only about one and a half inches long. The sperm's journey through the epididymis takes about 3 weeks.
The fluid in which the sperm is transported contains sugar in the form of fructose, which provides energy as the sperm matures. In the early stages of its passage, the sperm cannot swim in a forward direction and can only vibrate its tail weakly. By the time the sperm reaches the end of the epididymis, however, it is mature and looks like a microscopic squirming tadpole.
At maturity, each healthy sperm consists of a head that contains the man's genetic material, his DNA, and a tail that lashes back and forth at great speed to propel the head forward at about four times its own length every second. The ability of a sperm to move forward rapidly and straight is probably the most significant determinant of male fertility.

Ejaculation. When a man experiences sexual excitement, nerves stimulate the muscles in the epididymis to contract, which forces the sperm out through the penis:

In the penis, the sperm first pass into one of two rigid and wire-like muscular channels, called the vasa deferentia. (A single channel is called a vas deferens.)
Muscle contractions in the vas deferens from sexual activity propel the sperm along past the seminal vesicles. These are clusters of tissue that contribute fluid, called seminal fluid, to the sperm. The vas deferens also collects fluid from the nearby prostate gland. This mixture of various fluids and sperm is the semen.
Each vas deferens then joins together to form the ejaculatory duct. This duct, which now contains the sperm-containing semen, passes down through the urethra. (The urethra is the same channel in the penis through which a man urinates, but during orgasm, the prostate closes off the bladder so urine cannot enter the urethra.)
The semen is forced through the urethra during ejaculation, the final stage of orgasm when the sperm is literally shot out of the penis.

Click the icon to see an image of the vas deferens.

Semen. In addition to providing the fluid that transports the sperm, semen also has other benefits:

It provides a very short-lived alkaline environment to protect sperm from the harsh acidity of the female vagina. (If the sperm do not reach the woman's cervix within several hours, the semen itself becomes toxic to sperm and they die.)
It contains a gelatin-like substance that prevents it from draining from the vagina too quickly.
It contains sugar in the form of fructose to provide instant energy for sperm locomotion.

The Path to the Egg. The sperm's passage to the egg is a perilous journey.

Usually about 100 - 300 million sperm are delivered into the ejaculate at any given time. Even under normal conditions, however only about 15% of these millions of sperm are sound enough to fertilize an egg.
To compound the problem, after the stress of ejaculation, only about 400 sperm survive the orgasm to complete the journey.
Out of this number, a mere 40 or so sperm survive the toxicity of the semen and the hostile environment of the vagina to reach the vicinity of the egg. Normally, the cervical mucus forms an impenetrable barrier to sperm. However, when a woman ovulates (releases her egg, the oocyte), the mucous lining thins to allow sperm penetration.
Sperm that manage to reach the mucous lining in the woman's cervix (the lower part of her uterus) must survive about four more days to reach the woman's fallopian tubes. (Here, the egg is positioned for fertilization for only 12 hours each month.)
The few remaining sperm that penetrate the cervical mucus and are able to reach the fallopian tubes become capacitated.
Capacitation is a one-time explosion of energy that completes the sperm's journey. It boosts the motion of the sperm and triggers the actions of the acrosome, a membrane that covers the head of the sperm and resembles a warhead. The acrosome is dissolved, and enzymes contained within it are released to allow the sperm to drill a hole through the tough outer coating of the egg.
In the end, only one sperm gets through to fertilize the egg.

Click the icon to see an image of the uterus.

Sperm Abnormalities

More than 90% of male infertility cases are due to low sperm counts, poor sperm quality, or both. In 30 - 40% of cases of sperm abnormalities, the cause is unknown. It may be the end result of one or more factors that include chronic illness, malnutrition, genetic defects, structural abnormalities, and environmental factors. Partial obstruction anywhere in the long passages through which sperm pass can reduce sperm counts. In one study, obstruction was believed to be a contributing factor in over 60% of low sperm count cases. Obstruction itself can be caused by many factors.

Sperm abnormalities are categorized by whether they affect sperm count, sperm quality, or sperm shape.

In the past, a sperm count of less than 40 million/mL in the ejaculate was believed to cause infertility. Now, however, if the woman is fertile and young, a count as low as 10 million can often accomplish conception over time, even without treatment. In fertilization clinics, men with low sperm counts report fertilization rates of about 30%, while those with average sperm counts have rates between 60 - 80%. Sperm count varies widely over time, and temporary low counts are common. Therefore, a single test that reports a low count may not be a representative result.

Sperm motility is the sperm's ability to move. If movement is slow, not in a straight line, or both, the sperm have difficulty invading the cervical mucous or penetrating the hard outer shell of the egg. If 60% or more of sperm have normal motility, the sperm is at least average in quality. If less than 40% of sperm are able to move in a straight line, the condition is considered abnormal. Sperm that move sluggishly may also have genetic or other defects that render them incapable of fertilizing the egg. An important 2001 study identified a protein in the tail of the sperm called CatSper, which might play a central role in the ability of the sperm to swim and penetrate the egg.

Morphology refers to the shape and structure of an object. Morphology may be even more important than count or motility in determining potential fertility. Abnormally shaped sperm cannot fertilize an egg. About 60% of the sperm should be normal in size and shape for adequate fertility.

The perfect structure is an oval head and long tail. Abnormally shaped sperm may include a number of variations:

A very large round head. (In one study, if 14% or more of sperm had round enlarged heads, the chances for pregnancy fell to about 20%. Such an abnormality indicates early unraveling of genetic material.)
An extremely small pinpoint head
A tapered head
A crooked head
Two heads
A tail with kinks and curls

Sperm carry half the genetic material necessary to make a complete human being. (The egg holds the other half.) Genes are contained in the rod-like structures called chromosomes. The genes themselves are made up of chains of molecules called DNA, which carry the information that defines a human. Genetically fragile sperm are important factors in male infertility. Such sperm have fragmented DNA chains, which make them less capable of fertilization and may also contribute to low quality.

Causes

In one study, the causes of infertility in men seeking to conceive included:

Vasectomy. In the study, 56% of men were seeking a reversal of this procedure. Thirty years ago, this was a factor in only 5% of men seeking help for fertility.
Varicocele (14%). A network of veins carries blood away from the testicles and back up into the body. If these veins become enlarged, twisted, and swollen (similar to varicose veins in the leg), this condition is termed a varicocele. Varicoceles can impair testicular function and fertility.
Unknown infertility (8%).
Absence of sperm (6%). There are many biologic and environmental factors that can lead to low sperm count. For instance, abnormalities in production or obstruction of the tubes that carry sperm can reduce sperm levels. A condition called Sertoli cell-only syndrome is one in which the cells that produce sperm (the Sertoli cells) are absent. This can be a congenital problem that a man is born with or caused by infection, injury, medication, radiation, or genetics. In addition, other conditions may cause infertility in men.

The effect of aging on male fertility is not totally clear. However, growing evidence suggests that it may be a factor (although not to the extent that it is in women). This evidence indicates that age-related sperm changes in men are not abrupt, but are a gradual process. Aging can adversely affect sperm counts and sperm motility (the sperm's ability to swim quickly and move in a straight line). A 2006 study also suggested that the genetic quality of sperm declines as a man ages. The researchers found that poor sperm motility was associated with DNA fragmentation. This led to some older men having an increased risk of passing on gene mutations that cause dwarfism and possibly other genetic diseases.

Nearly any major physical or mental stress can temporarily reduce sperm count. Some common conditions that lower sperm count, temporarily in nearly all cases, include:

Emotional Stress. Stress may interfere with the hormone GnRH and reduce sperm counts.

Sexual Issues. In fewer than 1% of cases, impotence, premature ejaculation, or psychological or relationship problems contribute to male infertility, although these conditions are usually very treatable. Lubricants used with condoms, including spermicides, oils, and Vaseline, can affect fertility. Astroglide, Replens, or mineral oil may not be as harmful to sperm. However, oil-based lubricants can damage latex condoms and should be avoided.

Testicular Overheating. Overheating, such as from high fevers, saunas, and hot tubs, may temporarily lower sperm count. Persistent exposure to high temperatures during work may impair fertility. Several studies have found no negative effects on fertility from wearing tight trousers, briefs, or athletic supports, even every day.

Substance Abuse. Cocaine or heavy marijuana use appears to temporarily reduce the number and quality of sperm by as much as 50%. Sperm actually have receptors for certain compounds in marijuana that may impair the sperm's ability to swim and also inhibit their ability to penetrate the egg. Alcohol does not appear to affect fertility, unless it is so abused that it causes liver damage.

Smoking. Smoking impairs sperm motility, reduces sperm lifespan, and may cause genetic changes that affect the offspring. One study found that men or women who smoke have lower success rates with assisted reproductive technologies. Another study reported that men who smoke also have lower sex drives and less frequent sex.

Malnutrition and Nutrient Deficiencies. Deficiencies in certain nutrients, such as vitamin E, vitamin C, selenium, zinc, and folate, may be particular risk factors for infertility

Obesity. Obesity may be a risk factor for male infertility. A 2006 epidemiological study found that a 20-pound increase in a man's weight increased the chance for infertility by about 10%.

Bicycling. Bicycling has been linked to impotence in men and also may affect fertility. Pressure from the bike seat may damage blood vessels and nerves that are responsible for erections. Mountain biking, which involves riding on off-road terrain, exposes the perineum (the region between the scrotum and the anus) to more extreme shocks and vibrations and increases the risk for injuries to the scrotum. One study found that men who mountain bike are far more likely to have scrotal abnormalities, including calcium deposits, cysts, and twisted veins. Men who cycle can reduce such risks by:

Taking frequent rests while biking
Wearing padded bike shorts
Using a padded or specially contoured bike seat that is raised high enough and sits at the proper angle

Problems in the genes that regulate male fertility and in the genetic material of sperm itself are important contributors to infertility problems in men. In fact, even in men with no known fertility problems, 19% of the sperm are genetically defective. Certain inherited medical conditions also contribute to male infertility. Defective genes themselves can be inherited, produced by environmental assaults (such radiation exposure), or both. Of some concern is the possibility that these mutations will be passed to offspring in men who undergo fertilization techniques that retrieve sperm and directly fertilize the egg. (Under natural conditions, genetically abnormal sperm would be very unlikely to reach and fertilize the egg.)

Defective Genetic Material. Sperm carry half the genetic material necessary to make a human being. Infertile men have been reported to have a relatively high percentage of sperm with broken or damaged DNA (the molecular chain that makes up a gene).

Genetic Factors Specifically Affecting Sperm Production or Quality. Abnormalities in genes that specifically regulate sperm production and quality are major factors in male infertility. Some research suggests that about 10% of cases of male infertility may be due to problems, most likely genetic, in the acrosome. The acrosome is the enzyme-filled membrane cap on the sperm -- its warhead -- that is critical for piercing the egg. In one study, pregnancy was impaired if 7% or more of sperm had abnormalities in the acrosome.

Inherited Disorders that Affect Fertility. Certain inherited disorders can impair fertility. Examples include:

Cystic fibrosis patients often have missing or obstructed vas deferens (the tubes that carry sperm). In fact, men whose infertility is caused by an inborn missing vas deferens have a 60% chance that they carry the gene for cystic fibrosis (even if they don't have the disease itself).
Klinefelter syndrome patients carry two X and one Y chromosomes (the norm is one X and one Y), which leads to the destruction of the lining of the seminiferous tubules in the testicles during puberty, although most other male physical attributes are unimpaired.
Kartagener syndrome, a rare disorder that is associated with a reversed position of the major organs, also includes immotile cilia (hair-like cells in lungs and sinuses that have a structure similar to the tails of sperm). Sperm motility may also be impaired by this condition.
Polycystic kidney disease, a relatively common genetic disorder that causes large cysts to form on the kidneys and other organs during adulthood, may cause infertility as the first symptom if cysts develop in the reproductive tract.

Exposure to toxins, chemicals, or infections may reduce sperm count by either affecting testicular function or altering hormone systems. The extent of the impact and specific environmental assaults involved, however, are often controversial. Some researchers believe environmental toxins are contributing to a general worldwide decline in male fertility. Data indicate that testosterone levels in American men may have declined over the last several decades. The reasons for this decline have not yet been determined. However, even if testosterone levels are declining, the proportion of men treated for fertility problems has not changed much over the past decade.

Free Radicals (Oxidants). The primary suspects in the link between environmental assaults and infertility are free radicals, also called oxidants. These are unstable molecules, usually containing oxygen, that are released as a by-product of many natural chemical processes in the body. Infections, chemicals, and other environmental assaults can produce high levels of these particles. High levels may even affect the genetic material in cells. Sperm are particularly vulnerable to the damaging effects of this oxidation process. There have been reports that significant levels of oxidants occur in the semen of about 25% of infertile men.

Exposure to Estrogen-Like and Hormone-Disrupting Chemicals. European studies have increasingly reported a worsening in male reproductive health and an increase in testicular and prostate cancers. Many investigators strongly suspect environmental causes, particularly excessive chemicals that disrupt hormones, as a major cause for both these events. Estrogen-like chemicals found in pesticides and other chemicals are of particular concern. Overexposure to estrogen in male animals reduces the number of Sertoli cells (the cells necessary for the initial development of sperm). Some hormone-disrupting chemicals under investigation include:

Treatment of prostate cancer varies depending on the stage of the cancer and may include surgical removal, radiation, chemotherapy, hormonal manipulation or a combination of these treatments.

Bisphenol A is a widely used chemical found in plastic food containers and bottles that has provoked concern. It has potent estrogen-like effects in low dose. Use of the chemical in female rats has produced prostate abnormalities in their male offspring.
Phthalates, chemicals used to soften plastics, are under particular scrutiny for their ability to disrupt hormones. Specific phylates of special concern include dibutyl phthalate (DBP), which is found in many products, including cosmetics and clay products sold to children (Fimo, Sculpey). Animals exposed to phylates have significantly impaired sperm count and abnormalities in their reproductive structures, such as the testes. In addition, there is some concern that exposure in pregnant women may affect the offspring,
Organochlorines are compounds that combine chlorine and organic substances -- usually petrochemicals. Many have estrogen-like effects, including those previously used to make plastics (PCBs) and pesticides (DDT and p,p-DDE). Some, such as dioxins and furans, are byproducts of many chemical processes. Fortunately, most of these chemicals have been banned, but they were heavily used in manufacturing before 1970 and are still widespread in the environment. Studies report that when men had a history of moderate or high on-the-job exposure to pesticides containing organochlorines, their fertility rates were lower than men without such exposures. Studies have found a strong correlation between high levels of polychlorinated biphenyls (PCBs) or p,p-DDE with reduced sperm quality and quantity. In one of the studies, even men with healthy sperm with high organochlorine levels had a lower sperm count than those with lower levels of these compounds.

Most evidence on the hormone of chemical estrogens has occurred in animals and birds. Tests of single chemicals containing estrogen have reported little danger for people. Some studies suggest, however, that exposure to more than one of these chemicals may be very harmful. At this time, there is no strong evidence supporting a serious harmful effect in people who have normal exposure to these chemicals. Major efforts are underway to determine the extent of any possible harm from these chemicals.

Exposure to Heavy Metals. Chronic exposure to heavy metals such as lead, cadmium, or arsenic may affect sperm quality. Trace amounts of these metals in semen seem to inhibit the function of enzymes contained in the acrosome, the membrane that covers the head of the sperm.

Radiation Treatments. X-rays and other forms of radiation affect any rapidly dividing cell, so cells that produce sperm are quite sensitive to radiation damage. Cells exposed to significant levels of radiation may take up to 2 years to resume normal sperm production and, in severe circumstances, may never recover.

Men with fertility problems because of low semen levels when they ejaculate may have a structural abnormality in the tubes transporting the sperm. (A normal amount of semen is 2.5 - 5 mL, or about 1/2 - 1 teaspoon.)

A varicocele is an abnormally enlarged and twisted (varicose) vein in the spermatic cord that connects to the testicle. Varicoceles are found in 15 - 20% of all men and in 25 - 40% of infertile men, although it is not clear how or even if they affect fertility. They tend to occur more commonly (85%) on the left side. Some theories supporting their possible effect on infertility include:

Click the icon to see an image of a varicocele.

Varicoceles may partially obstruct the passages through which sperm pass.
Varicoceles may elevate temperature in the testes.
Varicoceles may produce higher levels of nitric oxide, a substance that has beneficial effects on blood flow and other functions but which might, in excess, injure sperm.
Varicoceles may block oxygen supply to the sperm.
Varicoceles have been associated with abnormalities in cellular material in the sperm. One study suggested that some men with fertility problems may have genetic defects that cause both varicoceles and impaired sperm.

Some reports indicate that only varicoceles that are large enough to be felt (or palpable) may impact fertility. On the other hand, however, an 8-year study of men with and without varicoceles found no differences in sperm quality or in the ability to conceive. Furthermore, the few well-conducted studies on repair of varicoceles suggest that the procedure does not improve pregnancy rates. Their effect on fertility remains unclear.

Hypogonadism is the general name for a severe deficiency in gonadotropin-releasing hormone (GnRH), the primary hormone that signals the process leading to the release of testosterone and other important reproductive hormones. Low levels of testosterone from any cause may result in defective sperm production.

Hypogonadism is uncommon and is most often present at the time of birth, usually the result of rare genetic diseases affecting the pituitary gland that may include selective deficiencies of the hormones FSH and LH, Kallman syndrome, or panhypopituitarism, in which the pituitary gland fails to make almost all hormones. It can also develop later in life from brain or pituitary gland tumors or as a result of radiation treatments. Defects in the gene on the X chromosome that regulates receptors that bind to androgens (male hormone) may also prove to be very important causes of male infertility.

Click the icon to see an image of the pituitary gland.

Autoimmunity is a condition in which antibodies of the immune system attack specific cells in the body, mistaking them for foreign microinvaders. In the case of male infertility, these so-called autoantibodies ("self" antibodies) target the sperm. Antibodies bind to specific parts of the sperm, such as the head or tail and, depending on the site of attachment, cause various problems:

Sperm may stick together (agglutinate)
They may fail to interact with cervical mucous
They may be unable to penetrate the egg

Some experts believe that in most cases the presence of these antibodies will not prevent conception unless a large percentage of sperm are affected.

Vasectomy and Anti-Sperm Antibodies. Vasectomy, the primary sterility procedure in men, is the most common cause of sperm autoantibodies (also called anti-sperm antibodies). Their typical development may be as follows:

Vasectomy works by severing the vas deferens, the tube that carries sperm from the testicles to the urethra (which leads out of the penis).
After vasectomy, sperm continue to be produced but, instead of being confined to the reproductive passages, they leak out into the body.
Here, the immune system may perceive them as foreign invaders and develop antibodies to attack them.

Such antibodies often persist, even if a man restores sperm flow by a successful reversal procedure (vasovasostomy). The persistence of anti-sperm antibodies may result in infertility.

Click the icon to see an illustrated series detailing vasectomy.

Other Causes of Autoantibodies. Antibodies to sperm can also appear in men without previous vasectomies and have been reported to be present in 10% of all men with fertility problems. They may be linked to genital infections or injury, although the cause is usually not known.

Retrograde ejaculation occurs when the muscles of the urethra do not pump properly during orgasm and sperm are forced backward into the bladder instead of forward out of the urethra. Sperm quality is often impaired.

Retrograde ejaculation can be the consequence of several conditions:

Surgery to the lower part of the bladder or prostate (the most common cause of retrograde ejaculation)
Diabetes
Multiple sclerosis
Back surgery
Spinal cord injury

Medications such as tranquilizers, certain antipsychotics, or hypertension medications also may cause temporary retrograde ejaculation.

Any structural abnormalities that affect the testes, tubes, or other reproductive structures can have a profound effect on fertility.

Testicular Dysgenesis Syndrome. Testicular dysgenesis syndrome is a recently observed occurrence of three conditions -- impaired sperm production and quality, testicular cancer, and genital tract abnormalities. Environmental factors that increase damage from oxidants are believed to be responsible.

The genital abnormalities identified with this syndrome are undescended testes and hypospadias, each of which is associated with infertility:

Undescended Testes (Cryptorchidism). In some cases, there is a failure of the testes to descend from the abdomen into the scrotum during fetal life. Cryptorchidism is associated with mild to severe impairment of sperm production. In one survey, 38% of men who as youngsters had two undescended testicles and 10% of men with one undescended testicle were infertile, compared with 5% of men who had normal testes. Even one undescended testicle may impair fertility. In cryptorchidism, the testes are exposed to the higher internal body heat, but this may not totally explain the damage in sperm production that can occur. (Men who suffer from this condition should be aware that even if the testicle is surgically moved to the scrotum, their risk of testicular cancer is significantly increased, warranting careful self-exams and regular follow-up with a doctor.)
Hypospadias. This is a birth defect in which the urinary opening is on the underside of the penis, can prevent sperm from reaching the cervix if not surgically corrected.

Click the icon to see an image of an undescended testicle.

Click the icon to see an image of hypospadias.

Blockage in the Tubes that Transport Sperm. Some men are born with a blockage in the epididymis or ejaculatory ducts or other problems that later affect fertility. One center reported that 2% of men seeking treatment had no vas deferens.

Anorchia. In the very rare condition known as anorchia, a man is born without any testes.

Syringomyelia. This is a disease of the spinal cord that results in no ejaculate at all (aspermia).

Birth rates among cancer survivors are only 40 - 85% of normal rates. Certain cancers, particularly testicular cancer, impair sperm production, often severely. Cancer treatments such as chemotherapy and radiation can damage sperm quality and quantity, causing infertility. The closer radiation treatments are to reproductive organs, the higher the risk for infertility. Fortunately, while men may fail to produce sperm for as long as 5 years after radiation therapy, many men eventually recover their sperm production ability. Chemotherapy with drugs that harm reproductive function tends to affect fertility more severely in men than in women. New drug regimens are helping to improve fertility rates.

Adolescents and adult men undergoing cancer treatments who may want to father children should consider banking and freezing their sperm for later use in assisted reproductive therapies. This technique is called sperm cryopreservation. Sperm cryopreservation is recommended by the American Society of Clinical Oncology as the method with the highest likelihood of success for male cancer survivors. However, these banking methods are not appropriate for pre-adolescent boys being treated for childhood cancers such as leukemia. Researchers are investigating ways that stem cell transplantation may someday help these children regain their fertility while avoiding leukemia relapse.

There is some controversy over the effect of infections on infertility. Simply detecting the presence of an infection in infertile men does not necessarily mean that it has any relationship to the infertility itself. The immune response to some infections may release inflammatory factors and oxidants, chemically unstable particles that can damage sperm. The exact impact of this process on sperm is unclear, however. Infections may alter the liquidity of semen and sperm motility, although these are likely to be temporary effects. Among the infections most implicated in infertility are:

Sexually Transmitted Diseases. Repeated Chlamydia trachomatis or gonorrhea infections are most often associated with male infertility. Such infections can cause scarring and block sperm passage. Human papilloma viruses, the cause of genital warts, may also impair sperm function.

Mycoplasma. Mycoplasma is an infectious organism that appears to fasten itself to sperm cells and render them less motile.

Mumps. When mumps develops after puberty, it damages the testicles in 25% of men afflicted with the disease. (Interferon, an anti-viral drug, may help prevent infertility in adult males with active mumps, but the drug is highly toxic and caution is essential.)

Glandular Infections in the Urinary Tract or Genitals. Glandular infections that may affect fertility include prostatitis (in the prostate gland), orchitis (in the testicle), semino-vesculitis (in the glands that produce semen), or urethritis (in the urethra), perhaps by altering sperm motility. Even after successful antibiotic treatment, infections in the testes may leave scar tissue that blocks the epididymis.

Medical Conditions. Other medical conditions that can affect male fertility include any severe injury or major surgery, diabetes, HIV, thyroid disease, Cushing syndrome, heart attack, liver or kidney failure, and chronic anemia.

The effects of medications on sperm quality and count have not been rigorously studied, and many medicines are commonly prescribed without knowing whether they impair fertility. Anabolic steroids (which are often abused by weight lifters and other athletes) deserve special notice because they are known to severely impair sperm production. Among the other drugs that can affect male fertility are cimetidine (Tagamet), sulfasalazine (Azulfidine), salazopyrine, colchicine, methadone, methotrexate (Folex), phenytoin (Dilantin), corticosteroids, spironolactone (Aldactone), thioridazine (Mellaril), and calcium channel blockers.

Diagnosis

In any fertility work-up, both male and female partners are tested if pregnancy fails to occur after a year of regular unprotected sexual intercourse. It should be done earlier if a woman is over age 35 or if either partner has known risk factors for infertility. A work-up can not only uncover the causes of infertility but also detect other potentially serious medical problems as well, including genetic mutations, cancer, or diabetes.

The patients will provide the doctor with a detailed history of any medical or sexual factors that might affect fertility:

Frequency and timing of sexual intercourse
Duration of infertility and any previous fertility events
Childhood illnesses and any problems in development
Any serious illness (diabetes, respiratory infections, cancer, previous surgeries)
Sexual history, including any sexually transmitted diseases
Any exposure to toxins, such as chemicals or radiation
History of any medications and allergies
Any family history of reproductive problems

A fertility specialist, usually a urologist, will perform a physical examination. A physical examination of the scrotum, including the testes, is essential for any male fertility work-up. It is useful for detecting large varicoceles, undescended testes, absence of vas deferens, cysts, or other physical abnormalities.

Varicoceles large enough to possibly interfere with fertility can be felt during examination of the scrotum. In such cases, they are described as feeling like "a bag of worms." They disappear or are greatly reduced when the patient lies down, so the patient should be examined for varicocele while standing.
Checking the size of the testicles is helpful. Smaller-sized and softer testicles along with tests that show low sperm count are strongly associated with problems in sperm formation. Normal testicles accompanied by a low sperm count, however, suggest possible obstruction. The doctor may also take the temperature of the scrotum with a test called scrotal thermography.
The doctor will also check the prostate gland for abnormalities.
The penis is checked for warts, discharge from the urinary tract, and hypospadias (incorrect location of the urethra opening).

A urine sample to detect sperm after ejaculation may rule out or indicate retrograde ejaculation. It also may be used to test for infections.

The basic test to evaluate a man's fertility is a semen analysis. The sperm collection test for men who can produce semen involves the following steps:

A man should abstain from ejaculation for several days before the test because each ejaculation can reduce the number of sperm by as much as a third. To ensure an accurate sample, most doctors recommend abstaining from ejaculation for at least 2 days, but not more than 5 days, prior to semen collection.
A man collects a sample of his semen in a collection jar during masturbation either at home or at the doctor's office. Proper collection procedure is important, since the highest concentration of sperm is contained in the initial portion of the ejaculate. Specially designed condoms are also available that enable collection of a sample during sexual intercourse. (Regular condoms are not useful, since they often contain substances that kill sperm.)
The sample should be kept at body temperature and delivered promptly. If the sperm are not analyzed within 2 hours or kept reasonably warm, a large proportion may die or lose motility.
A semen analysis should be repeated at least three times over several months.

The sperm count test is performed if a man's fertility is in question. It is helpful in determining if there is a problem in sperm production or quality of the sperm as a cause of infertility. The test may also be used after a vasectomy to make sure there are no sperm in the semen.

The man and woman should both be present when the doctor discusses the results of this analysis so that both partners understand the implications. The analysis report should contain results of any abnormalities in sperm count, motility, and morphology as well as any problem in the semen. However, semen analysis alone is not necessarily a definitive indicator of either infertility or fertility.

In June 2007, the first at-home fertility test kit became commercially available. Fertell includes both male and female tests that allow couples to test sperm motility (for men) and follicle-stimulating hormone (for women). Results are available in less than 90 minutes, and are 95% accurate. The test is available on-line and at some pharmacies. It does not require a prescription. However, Fertell does not screen for all types of fertility problems and should not be used as a substitute for a professional evaluation by a doctor.

Sperm Count. A low sperm count should not be viewed as a definitive diagnosis of infertility but rather as one indicator of a fertility problem. Although in a large analysis sperm counts below 13.5 million were considered a strong indication of infertility, pregnancy was possible so long as any motile sperm were present. If there are no sperm cells at all in the semen, the doctor checks for obstruction in the tubes or for Sertoli cell-only syndrome, in which there are no sperm-producing cells in the testes. An at-home test (FertilMARQ) is now available to help gauge sperm quantity.

Sperm Motility. Motility (the speed and quality of movement) is graded on a 1 - 4 ranking system. For fertility, motility should be greater than 2.

Grade 1 sperm wriggle sluggishly and make little forward progress. (Sperm that, in fact, clump together may indicate that antibodies to the sperm are present.)
Grade 2 sperm move forward, but they are either very slow or do not move in a straight line.
Grade 3 sperm move in a straight line at a reasonable speed and can home in on an egg accurately.
Grade 4 sperm are as accurate as Grade 3 sperm, but move at terrific speed.

More than 63% of sperm should be motile for normal fertility, but even men whose motile sperm constitutes only about a third of the total sperm count should not rule out conception. Testing for sperm motility is particularly valuable for predicting the success of artificial insemination and which men might be candidates for the intracytoplasmic sperm injection (ICSI) fertilization technique, in which the sperm is inserted directly into the egg and motility plays almost no role.

Sperm Morphology. Morphology is the shape and structure of the sperm and, of the three main sperm values, may be the best predictor of fertility. Older reports indicated that about 60% of the sperm should be normal in size and shape for adequate fertility. However, one major analysis used a much broader range of criteria for sperm morphology and concluded that values over 12% were good predictors of fertility. Determining the morphology of the sperm is particularly important for the success of the fertility treatments in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

Seminal Fluid. The seminal fluid (semen) itself is analyzed for abnormalities. The color is checked and should be whitish-gray.

The amount of semen is important. Most men ejaculate 2.5 - 5 milliliters (mL) or cubic centimeters (cc) (1/2 - 1 teaspoon) of semen. Either significantly higher or lower amounts can be a sign of trouble:

Amounts greater than 1 cc but lower than 2.5 cc may indicate prostate problems or frequent intercourse.
A semen sample that is less than 1 cc could indicate a blockage of the ejaculatory ducts or other tubular abnormalities.
No ejaculate at all may signal retrograde ejaculation.
High amounts of ejaculate may, in some cases, also contribute to infertility.

The semen will be tested for how liquid it is. (Normal semen is liquefied within 20 minutes after adding certain enzymes.) Abnormal results suggest the following:

Overly sticky fluid suggests problems in the prostate gland (which adds fluid to sperm)
Overly watery fluid suggests lack of sperm

The amount of sugar (fructose) in sperm will be measured:

Since fructose is added to the semen in the epididymis, an absence of fructose indicates that an obstruction has occurred either in the vas deferens or the epididymis.
Conversely, if there is fructose in the semen but no sperm, then the channel from the epididymis is open but there is a defect in sperm production.

Other factors may also be measured:

White blood cell counts are taken to detect infection.
Low levels of a substance called inhibin B, which appears to be produced only in the testes, may indicate blockage or other defects in the seminiferous tubules.
Low levels of another compound, alpha-glucosidase, may also indicate blockage in the epididymis.

Blood tests are used for measuring several factors that might affect fertility:

Hormonal Levels. Tests for certain hormone levels are indicated if semen analysis is abnormal (especially if sperm concentration is less than 10 million per milliliter) or there are other indications of hormonal disorders.

Blood tests for testosterone and follicle-stimulating hormone (FSH) levels are usually taken first.
If testosterone levels are low, then luteinizing hormone (LH) are measured.

Low levels of FSH, LH, and testosterone indicate a diagnosis of hypogonadotropic hypogonadism. Very high FSH levels with normal levels of other hormones indicate abnormalities in initial sperm production. Usually this occurs only if the testicles are severely defective, causing Sertoli cell-only syndrome, in which sperm-manufacturing cells are absent. Other hormones, such as prolactin, estrogen, or stress hormones may be measured if there are symptoms of other problems, such as low sexual drive or the presence of breasts.

Infections. Blood tests can also determine the presence of any infections that might affect fertility, including HIV, hepatitis, and Chlamydia.

The postcoital test, also known as the cervical mucus penetration test, is designed to evaluate the effect of a woman's cervical mucus on a man's sperm. Typically, a woman is asked to come into the doctor's office within 2 - 24 hours after intercourse at mid-cycle (when ovulation should occur). A small sample of her cervical mucus is examined under a microscope. If the doctor observes no surviving sperm or no sperm at all, the cervical mucus should then be cultured for the presence of infection. The test cannot evaluate sperm movement from the cervix into the fallopian tubes or the sperm's ability to fertilize an egg.

If a man has had a vasectomy reversed and still cannot conceive or if semen analysis shows sperm clumping together, blood tests for anti-sperm antibodies will be conducted. Anti-sperm antibodies may also develop after genital infection or injury to the testes. The primary negative effect of these antibodies is to bind the sperm to the woman's cervical mucus, preventing the sperm from swimming further up.

Occasionally, a testicle biopsy may be performed, particularly for the following:

If Sertoli cell-only syndrome is suspected, in which sperm-producing cells in the testes are absent. It should be noted that specific cellular patterns can determine whether this condition is congenital (inborn) or caused by some later injury. This distinction is important in predicting the potential success of later sperm retrieval procedures.
For detecting obstruction in the transport system when sperm production looks normal but the count is low.

The standard biopsy procedure requires incisions (called an open approach) under anesthesia. It can be painful afterward. More than one biopsy may be needed in the case of suspected Sertoli cell-only syndrome, since one area may not have cell-producing cells, but other regions may contain normal sperm. Biopsies of both testes are more accurate than one. (Doctors must be careful to avoid the epididymis during a biopsy, since it is a continuous tiny tube and would be destroyed.) Patients may consider freezing any sperm retrieved during biopsy for later use.

Ultrasound imaging may be used to accurately determine the size of the testes or to detect cysts, tumors, abnormal blood flow, or varicoceles that are too small for physical detection (although such small veins may have little or no effect on fertility). It also can detect testicular cancer, which some experts believe make it worthwhile as a routine procedure for any male infertility work-up.

Click the icon to see an image of testicular ultrasound.

Genetic testing may be warranted in men who are severely deficient in sperm and who show no evidence of obstruction, particularly in men undergoing the intracytoplasmic sperm injection (ICSI) procedure. One study of men attending a fertility clinic showed that a third had genetic defects. If genetic abnormalities are suspected in either partner, counseling is recommended. Researchers are testing techniques such as preimplantation genetic diagnosis (PGD) that can examine all the chromosomes in a human embryo and detect defective genes, such as those for cystic fibrosis, at the very earliest stages. If it proves useful, it may help identify numerous abnormalities that increase the risk for infertility, treatment failures, or genetic defects in the offspring. In fact, a 2003 study suggested that performing an initial genetic analysis to determine DNA fragmentation in sperm may be a better way of predicting whether conception will succeed than analyzing semen.

In men who wish to undergo fertility treatments, certain tests will help determine the right strategies.

The Hamster Test. The hamster test, or micro-penetration assay test, uses the sperm sample to fertilize hamster eggs that have had their covering removed to allow penetration. If fewer than 5 - 20% of the eggs are fertilized, infertility is diagnosed. It may be useful for determining the best assisted reproductive treatment options for men with infertility.

The Human Zona Penetration Test. The human zona penetration test uses sperm to fertilize dead human eggs, which are usually obtained from an ovary that was removed for medical purposes. (Like the hamster test, the procedure cannot result in a living embryo.) Results may provide the same information as the hamster test and also indicate whether the sperm can penetrate the outer coating of an egg.

Acrosome Reaction Test. Tests that induce the ability of the sperm's enzyme-rich covering (acrosome) to dissolve can be very useful.

Other Tests. Additional advanced laboratory tests to measure sperm function, such as computer-aided sperm motility analysis, may also be performed. Some of these tests assess such factors as level of cell-damaging oxidants.

Treatment

Many men diagnosed with infertility in the past would be considered treatable now, even some men with spinal cord injuries. Unless a man produces no sperm at all, recent developments in treatment have made fertility possible for many men willing to undergo treatment and bear the expense. Before undergoing more advanced procedures, most couples trying to conceive should attempt some simple lifestyle changes.

Both male and female hormone levels fluctuate according to the time of day, and they also vary from day to day and month to month. Some timing tips might be helpful.

Male Hormone Levels and Sexual Activity. Male hormone levels are highest in the morning. In one study of men, their sexual activity was highest in October, when conception rates were also high.

Fertility and Seasonal Changes. Different studies have reported higher sperm counts in the winter than in the summer. For women, fertility rates as measured by treatment success are highest in months when days are longest.

Monitoring Basal Body Temperature. To determine the most likely time of ovulation and therefore the time of fertility, a woman is instructed to take her body temperature, called her basal body temperature. This is the body's temperature as it rises and falls in accord with hormonal fluctuations.

By studying the temperature patterns after a few months, couples can begin to anticipate ovulation and plan their sexual activity accordingly. Couples must try to avoid becoming fixated on the chart, however, in scheduling their sexual activity. Spontaneity can be lost, and the stress on the relationship can be quite severe.

Hormone Monitoring Systems for Women. A device called a saliva fertility monitor (Fertility Tracker) uses a microscope to view slides containing saliva and monitors estrogen levels. Home test kits that monitor reproductive hormone levels in the urine are also available. They are less costly than the saliva test but are messier. Monitoring hormone levels helps to determine when a woman is ovulating.

Frequency of Intercourse. The question of how often a couple should have intercourse is in debate. Some experts say that having sex more than 2 days a week adds no benefits. And, in fact, frequent sexual activity lowers sperm count per ejaculation. Some studies have indicated, however, that having intercourse every day, or even several times a day, before and during ovulation, improves pregnancy rates. Although sperm count per ejaculation is low, a constantly replenished semen supply is more likely to result in a fertilized egg.

Everyone should eat a healthy diet rich in fresh fruits, vegetables, and whole grains. Replace animal fats with monounsaturated oils, such as olive oil. Fish is also a good choice, and fish oils may have benefits for men with infertility. Certain specific nutrients, vitamins and minerals may also improve fertility.

Higher antioxidant intakes of vitamin C, vitamin E, and beta-carotene may help improve sperm numbers and motility, according to a 2005 study. The study included both food and supplement sources.
Vitamins C and E may also help repair DNA damage to sperm. According to a 2005 study, men who took 1 gram per day of these vitamins significantly reduced their percentage of DNA sperm fragmentation within 2 months.
The dietary supplements L-carnitine and L-acetylcarnitine may help improve sperm motility, according to several recent clinical trials.

A man who wants to increase his sperm count should also pursue a healthy lifestyle.

Avoid cigarettes and any drugs that may affect sperm count or reduce sexual function.
Overweight men should try to reduce their weight.
Get sufficient rest, and exercise moderately but regularly. (Those who exercise excessively might cut back, but not stop altogether.)
Stress may contribute to reduced sperm quality. It is not known if stress reduction techniques can improve fertility, but they may help couples endure the difficult processes involved in fertility treatments.
Although studies now indicate that tight underwear and pants pose no threat to male fertility, there is no harm in wearing looser clothing.
To prevent overheating of the testes, men should avoid hot baths, showers, and steam rooms.

The fertility process is a roller coaster of emotions that are present throughout both failure and success. There are almost no sure ways to predict which couples will eventually conceive. Some couples with multiple problems will overcome great odds, while other seemingly fertile couples fail to conceive. Many of the new treatments are remarkable, but a live birth is never guaranteed. The emotional burden on the couple is considerable, and some planning is helpful.

Planning for Emotional Turmoil.

Decide in advance how many and what kind of procedures will be emotionally and financially acceptable and attempt to determine a final limit. Fertility treatments are expensive.
Determine alternatives (adoption, donor sperm or egg, or having no children) as early as possible in the fertility process. This can reduce anxiety during treatments and feelings of hopelessness in case conception does not occur.

Managing Emotional Stress During the Process. Managing negative emotions in both men and women can be viewed as important as medical treatment. The process of fertility evaluation can be very difficult for many men. In a 2003 study, over 10% of men who required a second semen sample were unable to collect a semen sample using masturbation. Such men had had no problems with a first collection, but after being asked for additional samples they suffered severe anxiety during both masturbation in the fertility clinic and during regular sexual activity at home. Numerous studies reported a significant association between psychologic factors, particularly anxiety, and fertility treatment failure in women.

Managing the Emotional Effects of the Outcome. After enduring the process of fertility evaluation, the couple must face the outcome, and even a positive outcome has emotional repercussions.

Effects of Failure. Needless to say, the emotional stress of failure can be devastating even on the most loving and affectionate relationships and even in those who have prepared for the possibility of failure. Neither the male nor female partner should hesitate to seek professional help if the emotional burdens are too heavy.
Effects of Genetic Testing. As advanced technologies allow testing and greater genetic information at the earliest stage, potential parents will have to learn to deal with the uncertainties of possible chromosomal abnormalities, which may or may not be significant.
Effects of Multiple Births. A successful pregnancy that results in a multiple birth introduces new complexities and emotional problems. One study reported a very high rate of depression in women with triplets, particularly if they had little help from others, and especially if their husbands weren't involved.
Effects on Parenting. Once the fertility treatment-assisted child arrives, parents (both men and women) are more likely to be anxious and to have less confidence than those who conceive naturally.

Assisted Reproductive Technologies

Assisted reproductive technologies (ART) are medical techniques that help couples conceive. These procedures involve either:

A couple's own eggs or sperm
Donor eggs, sperm, or embryos

Fertilization may occur either in the laboratory or in the uterus. In the U.S., the number of live birth deliveries from ART increased by 128% from 1996 - 2002. More than 45,000 babies are now born in the U.S. each year using assisted reproductive technologies.

ART includes fertility drug treatments, artificial insemination (AI), in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and other procedures.

Choosing a good fertility clinic is important. The government does not always regulate centers offering assisted reproductive techniques, and abuses have been reported, including lack of informed consent, unauthorized use of embryos, and failure to routinely screen donors for disease.

The clinic should always provide the following information:

The live-birth rate (not just pregnancy success rate) for other couples with similar infertility problems. (Multiple births, such as twins or triplets, are counted as one live birth.)
Such statistics should include high-risk women, such as those who are older or fail to produce eggs. (Some disreputable clinics give success percentages that exclude high-risk women from their total, thereby making the percentage of success much higher.)

Advanced fertility procedures and medications are extremely expensive and often not covered by insurance. Couples should be cautious about offers of rebates in the event of failure. The clinics offering them are often significantly more expensive than those that don't.

Artificial insemination it is the least complex of the assisted reproductive technologies and is often tried first in uncomplicated cases of infertility. Artificial insemination either involves placing the sperm directly in the cervix (called intracervical insemination) or into the uterus (called intrauterine insemination, or IUI). IUI is the standard artificial insemination procedure.

It is useful under the following circumstances:

When the woman's cervical mucus is unreceptive.
When donor sperm are required.
If the man's sperm count is very low (although it is preferable if at least 5 million per milliliter are motile).
When unexplained infertility exists in both partners.

Those in whom artificial insemination fails, couples with specific fertility defects, or older women may be candidates for more advanced reproductive technologies.

Pregnancy Rates. A review of 45 studies reported that in unexplained infertility cases, the per-cycle pregnancy rates were 4% for intrauterine insemination (IUI) alone and 8 - 17% per cycle for IUI combined with superovulation, a procedure that uses fertility drugs to bolster egg recovery.

Researchers in one study suggested IUI as a reasonable first option for many women under age 43. It is less expensive and poses less risk for multiple births than the more advanced assisted reproductive technologies (ART), such as in vitro fertilization. Although in vitro fertilization procedures are more effective per cycle, couples tend to be able to afford more IUI cycles, so the pregnancy rates over time are very similar.

The Artificial Insemination Procedure. The artificial insemination procedure is as follows:

A woman usually (but not always) takes fertility drugs in advance.
The man must produce sperm at the time the woman is ovulating.
The sperm are subjected to certain so-called "washing" procedures. They are then inserted into the uterine cavity through a long, thin catheter.

The administration of fertility drugs and sperm retrieval is timed so that the process can coincide with time of ovulation. One study suggested that women who lay quietly for 10 minutes after sperm were implanted had a significantly higher rate of pregnancy than those who got up immediately.

Intracytoplasmic sperm injection (ICSI) is an assisted reproductive technology used for couples when male infertility is the main factor. It involves injecting a single sperm into an egg obtained from in vitro fertilization (IVF). The procedure is very simple:

A tiny glass tube (called a holding pipet) stabilizes the egg.
A second glass tube (called the injection pipet) is used to penetrate the egg's membrane and deposit a single sperm into the egg.
The egg is released into a drop of cultured medium.
If fertilized, the egg is allowed to develop for 1 - 2 days and then is either frozen or implanted.

The greatest concern with this procedure has been whether it increases the risk for birth defects. However, several studies have reported no higher risks of birth defects in children born using ICSI procedures. While other studies have shown a higher number of birth defects in children conceived with ICSI, the results may have more to do with the genetic background of the parents than ICSI itself. A 2006 study of 8-year-old children conceived with ICSI, meanwhile, found no important differences between these children and children who were conceived naturally.

A 2007 study in the New England Journal of Medicine indicated that ICSI use has increased 5-fold over the past decade, even though the proportion of men receiving treatment for male infertility has remained the same. In 1995, 11% of IVF cycles used ICSI. By 2004, 57.5% of IVF cycles used ICSI.

While ICSI is an important assisted reproductive technology for male infertility, it may be overused. Some doctors recommend ICSI for women who have failed prior IVF attempts or who have few or poor-quality eggs, even if their male partners have normal semen measurements. There is little evidence that ICSI helps improve pregnancy success for couples who do not have a problem with male factor infertility, according to the Society for Assisted Reproductive Technology.

About 71% of ART procedures now use in vitro fertilization (IVF) with the woman's own eggs. An in vitro procedure is one that is performed in the laboratory. Advances in these procedures have dramatically increased the rate of live births.

The best candidates for IVF are women with damaged fallopian tubes, and some experts believe it is a better option than attempting surgical repair. IVF is also used when infertility is unexplained or when the male partner has the infertility problem. A typical IVF procedure is as follows:

The doctor first induces superovulation using fertility drugs so that several eggs can be harvested from the ovary before they have been released from the follicles. Higher doses of fertility drugs for subsequent cycles do not appear to add any advantage in women who have a poor response the first time.
To harvest eggs, the doctor generally inserts a probe into the vagina and is guided by ultrasound. A needle is then used to drain the liquid from the follicles, and several eggs are retrieved.
The eggs and sperm are combined in a Petri dish. Between 48 - 72 hours later the eggs are fertilized.
The resulting embryos (the first stage toward the development of the fetus) are reimplanted into the woman's uterus.
It takes about 2 weeks to determine if the process is successful.

IVF success rates for the first three cycles of treatment are about equal. They then decline modestly for the fourth cycle and drop significantly after the fifth cycle.

Gamete/Zygote Intrafallopian Transfer. Gamete intrafallopian transfer (GIFT) and zygote intrafallopian transfer (ZIFT) are adaptations of IVF. GIFT and ZIFT are used in unexplained female infertility and in mild male infertility. The success rates are similar to those of IVF, but a woman must have at least one functioning fallopian tube.

GIFT: The procedure is as follows:

The eggs are harvested as in IVF.
They are mixed with the sperm but not actively fertilized.
They are immediately injected back into the woman. Laparoscopy, a technique that employs a miniature viewing device, is used with this procedure to guide the placement of the embryos or egg through a long, thin catheter into the fallopian tubes.
The sperm and egg are placed exactly where they would be in natural fertilization.

ZIFT: The procedure is as follows.

The eggs are harvested as in IVF.
They are then mixed with the sperm and, in this case, are fertilized in the laboratory.
They are then implanted in the fallopian tubes as in GIFT. (The advantage of this procedure over GIFT is that the doctor and couple are assured that fertilization has taken place and the eggs can be examined for defects before implantation.)

Success rates have increased in all age groups (although they are still considerably lower in older than in younger women). Chances for assisted reproductive technology success are also greater among women who do not have uterine abnormalities and have had previous successful pregnancies.

Success rates are also higher or lower depending on whether the woman uses her own eggs or whether they are donated and also whether the eggs are fresh or frozen. The highest live birth rates are with donated fresh eggs (an average of 50% per transfer) and the lowest rates are when a woman uses her own frozen eggs (an average of 29% per transfer). However, using frozen eggs is less expensive than fresh eggs, so a couple may be able to afford more cycles with frozen eggs.

Use of Donor Eggs. Older women are more likely to use donor eggs. In one study, success rates were the same for women who used donors with an age range of 20 - 40. There were also no differences in delivery rates for recipients up to age 45. Women over age 45, however, increasingly had problems with implantation, pregnancy, and delivery.

Use of Frozen Eggs. Frozen eggs tend to have lower success rates because of toxins released by cells damaged in the freezing and thawing tissues.

In Vitro Maturation. A new technique called in vitro maturation allows fertilization without the use of fertility drugs. In this process, follicles are harvested a few days before ovulation. In such cases, up to 50 have already begun to mature. About 15 of these maturing follicles can be removed, out of which 2 or 3 can produce healthy embryos.

Blastocyst Transfer. Blastocyst transfer is very promising. Instead of implanting the standard 2- or 3-day-old embryos in the uterus, the procedure implants blastocysts, which are more complex, 5-day-old embryos. Fewer blastocysts than embryos need to be implanted, reducing the risk for multiple births. (There is, however, a higher risk for identical twins compared to other procedures.) Offspring may be more likely to be males than females. Pregnancy rates are about 36% with a first attempt but then drop significantly. The procedure is more likely to be successful in younger than older women.

Ooplasmic Transfer. Ooplasmic transfer is a controversial experimental procedure that uses the woman's own egg and a female donor's egg and the male sperm for fertilization. Genetic material from the donor's egg plus the sperm are added to the woman's own egg. This has been successful in a few cases, but studies are very early and long-term effects are unknown. Research on this and similar procedures are currently conducted outside the United States.

Before fertilization using intrauterine insemination (IUI) or advanced assisted reproductive technologies (ART) can take place, the sperm must be collected and prepared for optimal chances for success.

Retrieval Procedures

When a man has no available sperm in the ejaculate (usually from blockage, vasectomy, or lack of vas deferens), the sperm must be retrieved from the testes or the epididymis. Various microsurgical techniques are now available for retrieval. The procedure may be done under local or general anesthesia, using a spring-loaded biopsy device, a thin needle, incisions, or microsurgical techniques.

Surgical Biopsy. In men without obstruction, sperm can be retrieved using a surgical testicular biopsy.

Testicular Fine Needle Aspiration. With testicular fine needle aspiration (TFNA), the surgeon uses a fine needle to remove sperm. This can be performed with local anesthetic and by surgeons who do not have to be experienced in microsurgeries.

Microsurgical Epididymal Sperm Aspiration. Microsurgical epididymal sperm aspiration (MESA) uses microsurgical techniques to collect sperm that are close to blocked portions of the epididymis. It involves an open incision and may be done under general or spinal anesthesia in a hospital setting, although the patient can often go home the same day. The doctor accesses the epididymis and retrieves sperm with an extremely fine needle-like device. It has the advantage that it can retrieve the largest number of sperm compared to other procedures. However, as with any invasive procedure, it carries some risks of complications, such as bleeding or infection.

Percutaneous Epididymal Sperm Aspiration. Percutaneious epididymal sperm aspiration (PESA) uses a needle to obtain mature sperm from areas in the upper parts of the epididymis (the coiled tube where sperm are stored before ejaculation). It is done under local anesthesia, sometimes in the doctor's office, is less expensive than other techniques, and recovery is fairly painless. However, it has less of a chance of achieving sufficient sperm than MESA, and there is also a chance of hitting a blood vessel, causing bleeding.

Testicular Sperm Extraction. Testicular sperm extraction (TESE) is a microsurgery that removes a small amount of tissue from one or more areas of the testes using incisions and microsurgery techniques. The tissue is placed in a culture and chopped into tiny pieces. Sperm are liberated from the tiny tubes and extracted. It is a complex process, however. This is the second best method for men with vasectomies, according to some experts. It is more painful than PESA, however. In addition, if the procedure is repeated too often, it can cause permanent alterations in testicular function that may even reduce male hormone levels.

Testicular Sperm Aspiration. Testicular sperm aspiration (TESA) uses a needle-like biopsy device to draw a small sample of testicular tissue. Multiple attempts are sometimes required to retrieve sperm, and it is not as effective or as safe as TESE, although imaging techniques using ultrasound may improve results.

Sperm Washing

A sperm's energy output is 20 times greater once it is removed from the seminal fluid. Methods for washing sperm can have a dramatic effect on the ability of sperm to move towards the egg. The simplest method involves:

The sperm is mixed with a nutrient-rich fluid (or culture media) in a test tube.
They are then centrifuged (spun very rapidly) for about 5 minutes.
The sperm, which are heavy, settle on the bottom, forming a dense button of millions of pure sperm. The fluid left on top is siphoned off.
This procedure may be repeated.

This simple method of sperm washing, however, does not eliminate heavy debris, such as dead sperm, white blood cells, or bacteria, which may impair fertility. Scientists are developing new techniques, such as adding a substance called platelet-activating factor during the sperm washing process, which may enhance pregnancy rates.

Swim-Up Technique

The swim-up technique is not only a useful diagnostic procedure for testing the ability of sperm to escape from the semen into the cervical mucus, but it also achieves the goal of removing sperm from semen.

A specially prepared semen sample is placed in a tube.
A culture media (a nutrient-rich substance in which cells thrive) is placed on top of the sample.
The medium is a hospitable environment for sperm, and those that are healthy will swim up to it.
After an hour or more, the culture is examined, and the number of sperm that have reached the medium is compared to the number still remaining in the semen.

The result gives a fair estimation of the number of sperm potentially capable of fertilization. It is superior to sperm washing because the live sperm will swim up to the culture media, leaving behind most of the debris, although some may float up into the medium. There is also some evidence that such sperm may have fewer genetic abnormalities than those retrieved through sperm washing. The strongest sperm, which are those at the top of the medium, can be collected for in vitro fertilization or artificial insemination. A good swim test yields about half a million very active sperm.

Freezing Sperm

Sperm can be fresh or frozen in advance. Studies are reporting that frozen sperm provide excellent results and can be used confidently for fertilization procedures. Fresh sperm, however, are preferred by some centers for cases when low sperm count is not caused by obstruction.

Complications of Assisted Reproductive Technology

Since assisted reproductive technology (ART) procedures have become more widespread since 1980, multiple births have significantly increased. About 35% of all ART births are multiple ones, with 4.3% being triplets or more. Multiple births increase the risk of complications, for both the mother and the child.

Assisted reproductive technology (ART), and multiple births, increase the risks for pregnancy complications. According to a 2005 study, the type of complications may depend on the infertility treatment:

Fertility drugs. Increase risks of the placenta becoming detached from the uterus (placental abruption), third trimester miscarriage, and gestational diabetes.
IVF. Increase risks of placental abruption, the placenta developing in the lower section of the uterus (placenta previa), dangerously high blood pressure during pregnancy (pre-eclampsia), and Caesarean sections.

Multiple births can also increase the risk of pregnancy death. A 2006 study indicated that women who carry multiple fetuses have a 3.6 times greater risk of dying from pregnancy complications than women with singleton pregnancies. The leading causes of death were blood clot (embolism), high blood pressure complications, excessive bleeding (hemorrhage), and infections.

The main risks for children conceived with assisted reproductive technology (ART) are complications associated with pregnancy problems and multiple births. Children conceived with ART are more likely to be born premature and to have extremely low birth weight. These conditions increase the risk for heart and lung problems, as well as learning and developmental disabilities. Premature delivery is also associated with cerebral palsy, a brain injury condition that affects muscle coordination. A 2006 study indicated that children born after in vitro fertilization have an increased risk for cerebral palsy.

However, unlike earlier research, recent studies suggest that ART does not increase the risk for chromosomal damage or other major birth defects. Couples undergoing ART may have other factors, such as older age or genetic predispositions, which make complications more likely. Infertility itself, even without ART, can pose a risk factor for birth defects. Children conceived naturally by couples with fertility problems tended to have more disorders of the nervous system, digestive system, and musculoskeletal system than children born to fertile couples, according to a 2006 study in the British Medical Journal. Children born to couples treated for infertility with ART may also have a slightly increased risk for these problems, as well as genital organ malformations, but the overall risk for birth defects appears to be very small.

Preimplantation genetic diagnosis (PGD) is now available in a few fertility centers. It can help identify genetic defects in the offspring and may help parents determine future problems. Such testing, however, also raises significant emotional issues that should be addressed beforehand.

Given the hazards of multiple births, parents must make some hard decisions if the treatment produces multiple embryos. The choices are limited:

Carry all of them to term, which increases health risks for both the mother and the developing fetuses
Complete abortion
Embryo reduction, in which the doctor removes one or more embryos (possibly endangering the remaining embryos)

At this time, the best approach is to limit the number of implanted embryos in the first place. Experts are attempting to develop methods to reduce the risk for multiple births:

Most centers now implant two to three embryos at a time, and the remainder can be frozen for future use. (Frozen eggs do not appear to pose a risk for developmental problems in children conceived using them.) This limits the chance for success, but implanting more than three embryos only increases success rates very slightly, whereas the risk for multiple births increases significantly.
Reducing the dosage of fertility drugs also reduces the risk for multiple births, but not significantly and it too reduces the chance for successful outcome.
Blastocyst transfer may help reduce the chances for multiple births.

Other Treatments

Hormone therapy has been effective for women with infertility problems, but has been disappointing in men except in a few specific cases:

Gonadotropin-releasing hormone (GnRH) is often very helpful in restoring fertility in men with gonadotropin deficiency and hypogonadism.
GnRH may be useful for restoring sperm production after chemotherapy treatments.
Sperm production occasionally responds to low doses of estrogen and testosterone or testosterone alone, menotropins (Pergonal, Repronal), clomiphene citrate (Clomid), human chorionic gonadotropin (hCG), or human follicle-stimulating hormone (r-hFSH, Gonal-F).
Prolonged treatment with follicle-stimulating hormone (FSH) prior to intracytoplasmic sperm injection (ICSI) may improve implantation rates.
Aromatase inhibitors block aromatase, an enzyme that is a major source of estrogen in many major body tissues. These drugs include anastrozole (Arimidex) and letrozole. (Femara). They may be helpful for specific men whose infertility is associated with abnormal testosterone-to-estrogen ratios.

Bromocriptine. Bromocriptine (Parlodel) is used in men whose infertility is related to excess prolactin manufactured by the pituitary.

Antibiotics. Infections interfering with fertility may be successfully treated with antibiotics.

Mast Cell Blocking Antihistamines. Studies report that certain antihistamines that block mast cells may be beneficial for some men with low sperm counts. Mast cells are inflammatory immune factors that may play a role in lower sperm quality. Studies have reported that two such drugs used overseas, ebastine and tranilast, improved pregnancy rates. Similar antihistamines in the U.S. are fexofenadine (Allegra), loratadine (Claritin), and cetirizine (Zyrtec).

Repair of a varicocele (varicocelectomy) in men with infertility problems is a common surgical practice. Nevertheless, although many urologists favor varicocele repair, the few well-conducted studies on this procedure suggest that it does not improve the chances for a successful pregnancy. Some experts argue that such studies were not using the most advanced techniques, which may be more effective. Some studies report that repair may improve the success rate of assisted reproductive technologies, such as intrauterine insemination (IUI). Still, the overall benefits remain uncertain, and additional rigorous trials are needed. In any case, the procedure does not appear to be beneficial for improving fertility in men whose varicoceles are very small.

Varicocele repair for fertility is sometimes considered when the following conditions are met:

When the varicocele can be felt during a physical examination.
Surgical treatment of varicoceles may be important in boys and adolescents to prevent later testicular damage.
When the male partner with varicoceles has abnormal semen quality or abnormal sperm function test results.
When the couple has known infertility, and the man has varicoceles but the woman is either fertile or can be treated for her infertility.

Varicocelectomy. Varicocelectomy, the standard repair procedure, involves tying off the swollen and twisted veins. Recovery takes 6 days, and most men cannot resume full activity for about 3 weeks. This technique eliminates 90% of varicoceles.

Recent surgical techniques use laparoscopy, which only requires tiny incisions (less than an inch). This approach allows for quicker recovery, although the procedure itself takes longer. It also has a higher rate of complications than the standard approach.

Varicocele Embolization. A nonsurgical technique called varicocele embolization may eventually prove to be an effective and less painful treatment for varicoceles, including those in young boys. It involves inserting a narrow tube (catheter) through a small incision in the neck or leg. Tiny steel plugs are passed through the catheter to block off the affected veins. The procedure takes 15 - 45 minutes to perform and uses local anesthetic. Some studies suggest that recurrence occurs in more than 10% of men, often requiring conventional surgery. This procedure is not yet widely available, and it may not be appropriate for some men.

Men with retrograde ejaculation and failure of emission caused by surgery, severe disease, or spinal cord injury are treated with various methods.

Drugs known as alpha-adrenergic agonists, including pseudoephedrine (Sudafed, Actifed), stimulate muscle contraction and help ejaculation. The tricyclic antidepressant imipramine (Tofranil) has similar effects, and in one analysis of 35 studies was more effective than pseudoephedrine. Promising investigational drugs include amezinium, which increases blood pressure.
If drugs are not effective, a technique called electrovibration (or electrical stimulation) is often beneficial. (Drugs in any case are not helpful for men with complete failure of emission.)

With any of these methods, the sperm can be collected for intrauterine insemination or assisted reproductive techniques. Spontaneous conception is possible, but not common, even with these treatments.

To prepare sperm for in vitro fertilization (IVF), men with retrograde ejaculation typically use sodium bicarbonate four times a day to reduce the acidity of the urine. After ejaculation, the man urinates or has a catheter (a tube) inserted to withdraw urine, which is then submitted for washing techniques to separate out the sperm.

Procedures that assist ejaculation are helping men with spinal cord injury conceive children. Vibratory or electronic stimulation is proving to be very beneficial for many of these men. The sperm retrieved using these methods are inserted into the women using self-insemination, intrauterine insemination, in vitro fertilizaiton, or intracytoplasmic sperm injection. Nearly a third of couples achieve pregnancy, a success rate that approaches natural conception.

Vasovasostomy. For men who wish to conceive after vasectomy, reversal surgery (vasovasostomy) may restore fertility. In vasovasostomy the severed ends of the vas deferens (which were cut during vasectomy) are reconnected to reestablish the flow of sperm. The reversal procedure is difficult. It involves sewing together the two ends of both tubes, each with pinhead sized openings. [See In-Depth Report #37: Vasectomy and vasovasostomy.]

Pregnancy Rates After Vasovasostomy. An Australian study reported that pregnancy rates in the late 1990s after reversal surgery were nearly four times higher than they were in the early 1980s. Pregnancy rates of over 50% are now being reported after a vasovasostomy. One study indicated that when successful conception occurs, it does at an average of 1 year after the surgery.

A successful reversal is more likely if the following conditions are present:

The section removed during vasectomy was not long
The original procedure was performed on straight sections of the vas deferens
The pieces joined during the vasovasostomy are of equal size

The closer in time the vasovasostomy is to the original vasectomy, the better. In one large study, the pregnancy rates were 76% for those who had vasectomy less than 3 years before reversal surgery, but decreased to 30% for those men who had a vasectomy more than 15 years earlier. The decrease in rates as time goes by is probably due to an increase in the chance for obstruction of the epididymis and the development of anti-sperm antibodies. Success rates, according to some studies, are slightly better if the male partner does not change female partners after the procedure. Other studies suggest that it makes no difference if the man has a new female partner. The age of the woman is an important factor, and the chances of achieving pregnancy are best for women younger than age 35. Some research suggests that men who have a vasectomy reversal may have a greater rate of sperm chromosomal abnormalities than normal fertile men.

Reversal Versus Assisted Reproductive Technologies. Even though newer techniques such as ICSI are improving pregnancy rates after vasectomy, vasovasostomy is still a better choice than assisted reproductive technologies (ART) for most men who want children.

Success rates with reversal surgeries are improving, and the costs are lower than with ART. In addition, a vasovasostomy does not pose a risk for multiple births. In one study, the pregnancy rate for vasovasostomy was 52%, whereas success after intracytoplasmic sperm injection (ICSI) was 25 - 30% (ICSI is the ART treatment of choice for men who have had vasectomy). Even for men who have failed vasovasostomy, a repeat procedure appears to be less expensive than embarking on fertility treatments at that time.

ART may, however, be a better approach than reversal for men with evidence of anti-sperm autoantibodies due to vasectomy. ICSI may also be more effective than reversal surgeries in men whose vasectomy was conducted at least 15 years or more beforehand.

Surgical Treatment of Obstructions. Obstructions in the area of the ejaculatory ducts have been successfully treated by excising or scraping the area where the prostate gland surrounds the urethra and by reconstructing the ducts.

Correcting Undescended Testicles. Undescended testicles of young boys may be repositioned surgically to prevent later infertility. It is important to perform the operation before 15 - 18 months of age to prevent the destruction of most of the sperm-producing cells, which occurs if the testicles remain in the abdomen.

Stem Cells. Researchers are investigating using sperm stem cells to treat male infertility. The research is still in its earliest stages. In 2004, researchers announced that they had successfully grown sperm progenitor cells in the laboratory. These types of cells could potentially develop into sperm cells capable of fertilizing an egg. This discovery was an important first step for developing stem cell infertility treatments.

Resources

www.resolve.org -- National Infertility Association
www.asrm.org -- American Society for Reproductive Medicine
www.urologyhealth.org -- American Urological Association
www.afafamilymatters.com -- American Fertility Association
www.ssmr.org -- Society for the Study of Male Reproduction
www.sart.org -- Society for Assisted Reproductive Technology
www.cdc.gov/ART/index.htm -- Centers for Disease Control: Assisted Reproductive Technology Report

References

Jain T, Gupta RS. Trends in the use of intracytoplasmic sperm injection in the United States. N Engl J Med. 2007 Jul 19;357(3):251-7.

Travison TG, Araujo AB, O'Donnell AB, Kupelian V, McKinlay JB. A population-level decline in serum testosterone levels in American men. J Clin Endocrinol Metab. 2007 Jan;92(1):196-202. Epub 2006 Oct 24.

Zhu JL, Basso O, Obel C, Bille C, Olsen J. Infertility, infertility treatment, and congenital malformations: Danish national birth cohort. BMJ. 2006 Sep 30;333(7570):679. Epub 2006 Aug 7.

Review Date:
10/17/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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adam.com

Non-small cell lung cancer

FitSugar — Wed, 08 Oct 2008 17:35:06 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Risk Factors
Lifestyle Changes
Diagnostic Tests
Staging Systems
Surgical Procedures
Radiation Treatments
Treatment Options by Stages...
Chemotherapy Treatments
Investigative Agents
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Research News:

About 3,000 nonsmokers die each year of lung cancer resulting from exposure to secondhand smoke, according to a 2006 Surgeon General report.
Advexin, a genetic therapy that contains the p53 tumor-suppressor gene, is showing promise. A 2006 study in Japan found that out of 13 patients with advanced NSCLC receiving Advexin, 10 had stabilized. Advexin is in Phase II clinical trials for NSCLC.
Studies are finding that NSCLC tumors in people who never smoked have a much higher rate of epithelial growth-factor receptor (EGFR) mutations. EGFR helps new blood vessels grow to feed tumors. This discovery may help tailor future treatments to specific patient populations. It also helps explain why some newer treatments seem effective mostly in patients who never smoked.

Treatment News:

Video-assisted thoracic surgery (VATS) is a new, less-invasive surgical technique that uses a thin tube containing a miniature camera and surgical instruments. Though the procedure is not appropriate in all cases, it offers significant advantages, especially in older or frail patients, in the treatment of early stage non-small cell lung cancer (NSCLC).
Bevacizumab, a monoclonal antibody, was approved in October 2006 as a first-line treatment (in combination with carboplatin and paclitaxel) for inoperable, locally advanced, metastatic, or recurrent non-squamous, non-small cell lung cancer.
Gefitinib (Iressa), a drug that targets EGFR, proved disappointing in final clinical trials. However, erlotinib (Tarceva), a drug that targets a different part of the EGFR molecule, has shown benefits. Erlotinib is now approved as a second-line chemotherapy to treat patients with locally advanced or metastatic NSCLC after a previous course of chemotherapy failed.

Introduction

Although lung cancer accounts for only 13% of all cancers, it is among the most lethal, accounting for over 28% of all cancer deaths. It is more deadly than colon, breast, and prostate cancers combined. An estimated 160,390 people will die from lung cancer in 2007. Death rates have been declining in men over the past decade, and they have now stabilized in women.

The lungs are two spongy organs surrounded by a thin moist membrane called the pleura. Each lung is composed of smooth, shiny lobes: the right lung has three lobes, and the left has two. About 90% of the lung is filled with air; only 10% is solid tissue.

Air is carried from the trachea (the windpipe) into the lung through flexible airways called bronchi.
Like the branches of a tree, the bronchi in turn divide into over a million smaller airways called bronchioles.
The bronchioles lead to grape-like clusters of microscopic sacs called alveoli.
In each adult lung, there are about 300 million of these tiny alveoli. A thin membrane makes up the alveoli sacs. Oxygen and carbon dioxide pass through this membrane to and from capillaries.
Capillaries, the smallest of our blood vessels, carry blood throughout the body.

The major features of the lungs include the bronchi, the bronchioles, and the alveoli. The alveoli are the microscopic blood vessel-lined sacks in which oxygen and carbon dioxide gas are exchanged.

Lung cancer develops when genetic mutations (changes) occur in a normal cell within the lung. As a result, the cell becomes abnormal in shape and behavior, and reproduces endlessly. The abnormal cells form a tumor that, if not surgically removed, invades neighboring blood vessels and lymph nodes and spreads to nearby sites. Eventually, the cancer can spread (metastasize) to locations throughout the body.

The two major categories of lung cancer are small cell lung cancer and non-small cell lung cancer. Most lung cancers are non-small cell cancer, the subject of this report. Less common cancers of the lung are known as carcinoids, cylindromas, and certain sarcomas (cancer in soft tissues).

Some experts believe all primary lung cancers come from a single common malignant (cancerous) stem cell that, as it copies itself, can develop into any one of these cancer types in different individuals.

In addition, cancers in the lung may have spread from other primary sites, such as the breast, thyroid, or colon. In these cases, doctors name the cancer after its original location; for example, "breast cancer with lung metastases."

Non-small cell lung cancers are categorized into three types: squamous cell carcinoma (also called epidermoid carcinoma), adenocarcinoma, and large cell carcinoma. These separate types are grouped together because, in early stages before the cancers have spread, they all can be treated surgically.

Squamous Cell Carcinoma. Squamous cells are formed from reserve cells, which are round cells that replace injured or damaged cells in the lining (the epithelium) of the bronchi, the major airways. Tumors formed from squamous cells are usually found in the center of the lung, either in a major lobe or in one of the main airway branches. They may grow to large sizes and form cavities in the lungs.

Click the icon to see an image of squamous cell carcinoma.

When squamous cell cancer metastasizes, it may travel to the bone, adrenal glands, liver, small intestine, and brain.

Squamous cell carcinoma is nearly always caused by smoking and used to be the most common cancer. It still makes up 25 - 40% of all lung cancers.

Adenocarcinoma. Adenocarcinomas usually arise from the mucus-producing cells in the lung. About two-thirds of adenocarcinomas develop in the outer regions of the lung, while one-third develop in the center of the lung. In 1965, 12% of lung cancers were adenocarcinomas. They are now estimated to account for 30 - 50% of all lung cancers and are the most common lung cancers in many countries. They are also the most common lung cancers in women. In fact, a 2000 European study showed that nearly 34% of the women with lung cancer under investigation had adenocarcinoma, compared to 26.4% who had squamous cell carcinoma, and 22.3% with small cell lung cancer. Adenocarcinoma is also increasing dramatically in men. Until recently, adenocarcinoma was only weakly linked to smoking. Experts now suggest, however, that the dramatic increase in recent decades in this lung cancer type may be due to low-tar, filtered cigarettes. People who smoke them draw tiny particles deeper into the lungs, thereby possibly increasing the risk for adenocarcinoma.

The course of this cancer varies widely. Most often, it develops slowly and causes few or no symptoms until it is far advanced. In some cases, however, it can be extremely aggressive and rapidly fatal. In 50% of cases in which this cancer spreads, it spreads only to the brain. Other common locations it spreads to include the other lung, the liver, the adrenal glands, and bone.

Click the icon to see an image of adenocarcinoma.

Bronchoalveolar Lung Cancer. Bronchoalveolar lung cancer is actually a subtype of adenocarcinoma. It develops as a layer of column-like cells on the lung and spreads through the airways, causing great volumes of sputum. This cancer also is increasing in incidence.

Large Cell Carcinoma. Large cell carcinoma, which makes up about 10 - 20% of lung cancers, includes cancers that cannot be identified under the microscope as squamous cell cancers or adenocarcinomas.

Click the icon to see an image of large cell carcinoma.

Small cell lung cancer may, like squamous cells, be derived from reserve cells or other cells in the epithelium. It causes 15 - 25% of all lung cancers; without chemotherapy, it is very aggressive and usually rapidly fatal. It requires a different treatment approach from non-small cell lung cancer, so it is not discussed in this report.

Click the icon to see an image of small cell carcinoma.

Causes

Cigarette Smoke. Smoking causes 87% of lung cancer deaths, accounting for 30% of all cancer deaths. Cigarettes, nicotine, or both may contribute to lung cancer in one or more of the following ways:

In general, chronic exposure to nicotine may cause an acceleration of coronary artery disease, peptic ulcer disease, reproductive disturbances, esophageal reflux, hypertension, fetal illnesses and death, and delayed wound healing.

The smoke is the most dangerous component of the cigarette. Chemicals formed during smoking trigger genetic mutations that lead to cancer. When people inhale cigarette smoke, they bring into their lungs tar that includes over 4,000 chemicals, some of which are carcinogenic (cancer-causing). Other inhaled chemicals in cigarette smoke that may increase the risk for cancer include cyanide, benzene, formaldehyde, methanol (wood alcohol), acetylene (the fuel used in torches), and ammonia. Smoke also contains nitrogen oxide and carbon monoxide, both of which are harmful gases.
Nicotine itself may be a hazard. A 2000 laboratory study suggested that the human body might be converting inhaled nicotine into a chemical called aminoketone, which has been linked to the formation of tobacco-related lung cancer. A 2001 study reported that nicotine triggered new blood vessel growth, which could, in theory, promote growth of any existing tumors. A study published in 2005 found that nicotine was responsible for disabling a gene that induces the death of cancer cells in lung tumors. Whether or not these studies apply to long-term use of nicotine replacement products (such as patches), or to cigarette smoking, is still unclear. The studies should certainly not discourage people from using nicotine replacement methods for quitting. However, these studies may indicate that people should not use these devices on a long-term basis.

Radon. Radon is a gas produced naturally by the breakdown of uranium. It is often present in the soil and in water and can seep into any dwelling. Radon may be responsible for between 10% and 14% of lung cancer deaths, making it, after smoking, the second leading cause of this cancer.

Other Contributors. Toxic particles leading to precancerous changes in the lung are also found in marijuana. In one study, 53.8% of cigarette smokers, 66.7% of marijuana smokers, and all of those subjects who smoked both substances showed evidence of precancerous changes in the lungs.

There is considerable debate over the lung cancer risk posed by depleted uranium used in military weapons (such as in the Gulf and Balkan conflicts). A 2001 study estimated that it would cause an additional 8 deaths from lung cancer out of every 10,000 people or soldiers who were highly exposed to this substance. The study was based on a mathematical model, however, and the issue is not settled.

Other lung carcinogens include asbestos, arsenic, certain petrochemicals (materials made from crude oil or natural gas), and other airborne (carried through the air) byproducts of various mining and manufacturing processes.

Click the icon to see an image of the tobacco plant.

Genetic mutations that cause cancer generally occur in two types of genes:

Tumor-suppressor genes, which prevent cells from endlessly copying themselves
Proto-oncogenes, which encourage cells to keep making copies of themselves [when a proto-oncogene changes (becomes mutated), it is then called an oncogene]

Damage to either type of gene can cause a mutation that results in an uncontrolled division of cells. This uncontrolled division forms tumors.

It is unlikely that a single specific abnormality causes all lung cancer. It probably takes a variety of mutations to start the devastating chain of events leading to cancer. The following mutations are among those under investigation:

BPDE-caused mutations: The chemical BPDE, a byproduct of tobacco smoke, is involved with a number of genetic mutations, including those to an oncogene called K-ras and to three tumor-suppressor genes known as p53, PPP2R1B, and p16. When normal, the tumor-suppressor genes are involved in cell repair and healthy copying of the cell. When they are damaged or blocked, out of control cell production can occur, leading to cancer. About 10% of the population may carry a gene that protects against lung cancer, by reducing levels of BPDE.
Chemotherapy resistance genes: Tumors that contain the p53 mutation may also be more resistant to chemotherapy.
Rb Mutations: Another important contributor to lung cancer is a genetically defective protein called retinoblastoma (Rb), which is associated with very aggressive tumors. Low levels of the normal Rb gene may sometimes predict aggressive cancer, especially in patients with small cell lung cancer.
Mutations to the FHIT gene: Another potentially important mutation may be an abnormality in the FHIT gene. This mutation causes the cells lining the lung to become more vulnerable to the effects of tobacco smoke and other carcinogens.

Symptoms

Lung cancer is unlikely to produce symptoms until the disease is advanced. When symptoms develop, they may result from the lung tumor itself, from its effects on tissues outside the lung, or from the spread of malignant cells to other organs.

Early symptoms may include the following:

Frequent bouts of pneumonia, or pneumonia that does not clear up in a normal period of time
Coughing (particularly coughing up blood)
Weight loss
Fever
Shortness of breath
Chest pain

Later-stage symptoms include the following:

Shortness of breath: This common symptom is the result of cancer that has spread in the lung and the pleura, the membrane covering the lung.
Superior vena cava syndrome: In some cases, tumor growth or spreading of the cancer presses against the superior vena cava, a large vein that returns blood from the upper part of the body to the heart. When this happens, a condition called superior vena cava syndrome may occur, leading to obvious swelling in the arms and face.
Trouble swallowing: The esophagus is the pipe that takes food from the mouth to the stomach. The cancer may spread to or press against the esophagus, interfering with swallowing and nutrition.
Hoarseness: Cancer can damage the nerves that control the voice box, causing hoarseness.
Pancoast syndrome: Damage to the brachial plexus, a group of nerves branching from the neck, can cause pain, weakness, or numbness in the arm or hand (Pancoast syndrome).
Bronchoalveolar lung cancer may produce very large amounts of mucus.
Hypercalcemia: Some lung cancers produce substances that remove calcium from bone and release it into the bloodstream, causing a condition called hypercalcemia. Patients with this disorder can experience nausea, vomiting, constipation, weakness, and fatigue.

Other lung cancers (usually small cell cancer) cause the body to retain water, lowering the blood's sodium levels. This condition, called hyponatremia, can produce confusion, weakness, and even seizures.

Risk Factors

Before cigarettes became popular in the beginning of the 20th century, lung cancer was rare. In 2007, lung cancer is expected to strike up to 213,380 Americans, and about 160,390 are expected to die from it.The disease usually occurs in people over 50 years old. Men have a significantly greater incidence of lung cancer compared to women. On the encouraging side, the rate of lung cancer in men has been declining significantly over the past decade. While lung cancer rates have been increasing dramatically in women (by 600% from 1950 to 2000), they now appear to be stabilizing.

Smoking appears to be the primary risk factor in 85 - 90% of lung cancers. About 15% of all people who smoke develop lung cancer. The risk depends on the duration of the addiction and the number of pack years. (One pack year equals the number of packs of cigarettes smoked per day, multiplied by the number of years that the person has smoked.) Genetic damage in the lung occurs in nearly all chronic smokers, even if cancer has not developed.

An elevated risk for lung cancer can persist for more than 20 years after quitting smoking, although the risk drops significantly even in the first year after quitting. And, there are benefits to quitting smoking even for people who are well into middle age.


Quitting Age	Percentage
30	2%
40	3%
50	6%
60	10%

Second-Hand Smoke. The Environmental Protection Agency has classified second-hand smoke as a carcinogen (cancer-causing chemical). Exposure to second-hand tobacco smoke increases the risk of lung cancer in the nonsmoker by about 20 - 30%. A 2006 Surgeon General report found that about 3,000 nonsmokers die each year of lung cancer resulting from exposure to secondhand smoke.

There may be some ethnic differences in lung cancer risk. For example, African-Americans face a risk that is two to four times higher than that in Caucasians, regardless of smoking status. It is not clear what factors are responsible for this higher risk. Some African-Americans appear to have a genetic vulnerability to the harmful chemicals in cigarette smoke.

In China, an estimated one third of all young male smokers will eventually die because of tobacco-related illnesses. Their risk for lung cancer, however, is much less than it is for chronic lung disease, the opposite of the Western trend. A 2001 study reported that the lower rate of lung cancer among Chinese people might be due to a slow rate of clearing nicotine, which results in smoking fewer cigarettes.

People with High Exposure to Radon. Studies have shown that radon raises the risk of lung cancer in underground miners by 40%. It is unclear whether the results of these studies would apply to people exposed to radon in their homes One study suggests that people with intense or prolonged exposure to radon in their homes do indeed face the same risk as miners exposed to similar levels of radon. A cumulative long-term exposure to radon and smoking also increases the danger. Most people move an average of 10 or 11 times over their lifetime, so the risk of developing lung cancer through radon exposure is very low in most individuals, even for those who lived for awhile in areas with high radon levels. People with homes that have high radon levels and those who sleep or spend many hours to days in basements with detectable but moderate levels should consider taking protective measures.

Workers Highly Exposed to Carcinogens. An estimated 9,000 - 10,000 men and 900 - 1,900 women develop lung cancer each year because of occupational exposure to carcinogens. More than half of these cases are attributable to past exposure to asbestos, which has long been known to be a risk factor for mesothelioma (cancer of the pleura, the lining around the lung) and can increase the risk of lung cancer in smokers. With better protective measures, these rates are expected to fall in the future.

Other chemicals that put workers at risk for lung cancer include:

Arsenic (insecticide and herbicide sprayers, tanners, oil refinery workers)
Chloromethyl methyl ether (workers exposed to certain polymers, water repellents, or products using chloride and formaldehyde)
Chromium compounds (workers using certain alloys, paints, pigments, and preservatives)
Depleted uranium (soldiers exposed to weapons during battlefield conditions)
Crystalline silica

By contrast, agricultural workers seem to have a lower lung cancer rate, despite their possible occupational exposures to risky chemicals. While this rate has traditionally been attributed to good health habits, including low tobacco use, a 2000 study suggests that agricultural workers' exposure to endotoxin may be responsible. Endotoxin is a component of common bacteria found in soil and animals and may have cancer-preventing effects on the immune system.

Exposure to Smoke from Grills. Grilling and high-heat frying emit chemicals called heterocyclic amines, which are known to be carcinogenic. A 2000 study of Chinese women found that smokers who stir-fried meat daily and inhaled cooking fumes had a higher risk of lung cancer than did those who stir-fried meat less frequently. No higher risk was found among nonsmokers.

Air Pollution. Although any risk from air pollution is very small, it nevertheless may be a contributor to those lung cancers not obviously related to smoking. Some studies, including a major analysis of vital statistics in 2002, have found an association between increased risk for lung cancer and long-term exposure to very small particulates, especially sulfates, present in polluted air. The risk, if any, is very small.

A family history of lung cancer may play a role in increasing susceptibility to this disease. In one study, people who had parents or siblings with respiratory tract cancers had a 30% higher risk for lung cancer, compared to people without a family history. Women with mothers or sisters with lung cancer had triple the risk. A higher risk occurred in both smokers and nonsmokers. There was no association between a history of other cancers and lung cancer. Both genetic factors and secondhand smoke appeared to contribute to the danger in these individuals.

Smokers with emphysema or chronic inflammatory lung diseases, such as asthma, are at increased risk for lung cancer. Both smokers and nonsmokers whose lungs are scarred from recurrent lung diseases, such as pneumonia or tuberculosis, are also at increased risk, particularly for bronchoalveolar lung cancer.

Lifestyle Changes

Quitting improves lung function almost immediately. Some evidence suggests that the benefits for the lungs are even more significant for women who quit than for men. It should be noted, however, that it can take 20 years or longer, particularly in heavy smokers, for the lungs to be restored to a fully healthy condition in which the risk for lung cancer is as low as for nonsmokers. Quitting is extremely difficult. No one should be discouraged if they relapse. Everyone should keep trying to quit. With continued efforts, many people succeed.

The many methods of quitting smoking include counseling and support groups, nicotine patches, gums and sprays, and incremental reduction.

At this time perhaps the most effective method for quitting is a combination of the following:

Nicotine replacement products that reduce withdrawal symptoms and cravings.
The antidepressants bupropion (Zyban) or nortriptyline (Pamelor, Aventyl), which reduce emotional effects and cravings associated with withdrawal, and improve abstinence rates.
Professional counseling or support organizations that may be effective, in addition to the medication, in helping people maintain abstinence.

[See In-Depth Report #41: Smoking.]

While people are in the process of quitting (and afterwards), they should maintain as healthy a lifestyle as possible.

Phytochemicals. Some data suggest that diets rich in fresh fruits and vegetables may be protective against lung cancer in both smokers and non-smokers. Some studies have reported protection from specific plant chemicals (phytochemicals), such as the following:

Isothiocyanates. These chemicals are found in cruciferous vegetables (broccoli, cauliflower, and Brussels sprouts). They may help block the effects of carcinogens in smoke, suppress tumor growth, and inhibit growth-promoting steroid hormones.
Flavonoids. Major sources are apples, grapefruit, onions, red wine, and tea. In one study on flavonoids, apple eaters had the lowest cancer risk, 68% less than those who ate fruit infrequently. In another, those who ate relatively more onions, apples, and white grapefruit had less than half the lung cancer risk as people who ate relatively small amounts of these foods. Flavonoids are also found in soybeans, berries, broccoli, carrots, citrus fruits, eggplant, peppers, squash, and tomatoes. Specific flavonoids in dark chocolate may be protective against lung cancer (but not other cancers).
Lycopene. Lycopene is found in tomatoes, which have been associated with a lower risk for lung cancer. Cooking the tomatoes appears to increase the potency of lycopene.
Cryptoxanthin. Some studies suggest that eating foods rich in cryptoxanthin, a yellow-orange pigment, reduces the risk for lung cancer. Foods with high amounts of cryptoxanthin include pumpkin, corn, papaya, red bell peppers, tangerines, oranges, and peaches. More research is needed in this area, however.
Isoflavones. Isoflavones, found in soy beans and flax seed, behave like estrogen in some ways and not in others. Some evidence suggests the genistein (a type of isoflavone) in soy may have properties that are protective against lung cancer.

Click the icon to see an image of phytochemicals.

Note: Studies on these chemicals are not consistent. It is unlikely that individual phytochemicals offer protection, but rather that the benefits come from a collection of vitamins and plant chemicals contained in fruits and vegetables. Fruit, especially, appears to be protective.

Fats and Oils. Some studies have indicated that diets high in animal fats increase the risk for lung cancer. Others have suggested some protection from cod liver oil, which contains omega-3 fatty acids (found in fatty fish), omega-6 fatty acids (found in flax and in soybean and canola oils), and monounsaturated oils (found in olive and canola oils). Of interest was a 2002 study reporting that women who had a high intake of cheese had a lower risk of lung cancer. Despite these intriguing pieces of information, the ability of these substances to protect against lung cancer remains controversial, and discontinuation of smoking remains the best advice.

Click the icon to see an image of fats and oils.

Vitamin Supplements. Even with a healthful diet, smoking reduces the levels of a number of vitamins, importantly vitamin C. There is no evidence, however, to support any protection from antioxidant supplements, including vitamins E, A, or beta carotene.

In fact, evidence is now suggesting that high doses of vitamin C, vitamin E, and beta carotene supplements may have harmful effects. A 2000 study, for example, reported a higher risk for cancer in male smokers who took multivitamins plus A, C, or E. The strongest studies to date on negative effects of antioxidant supplements have reported an increase in lung cancer and overall mortality rates among smokers who took beta carotene supplements. In determining reasons for this disturbing effect, one animal study suggested that beta carotene increased enzymes in the lungs that actually promote cancerous changes. In other words, antioxidants may actually be harmful in people who already harbor cancer cells. This is particularly important information for smokers, who may carry precancerous or cancerous cells for years prior to developing the disease. The best way of achieving healthy levels of important nutrients is from healthy foods.

Click the icon to see the benefits of vitamin A.

Click the icon to see dietary sources of vitamin A.

Trace Element Supplements. Trace elements may be important in cancer risk and prevention.

Selenium appears to inhibit cell production and may have other anti-cancer properties. A few studies have reported some protection with selenium. However, a major 2002 analysis supports previous work, indicating that taking selenium helps only people who are deficient to begin with.

Click the icon to see the benefits of selenium.

Zinc may prove to be more important than selenium. Some research suggests that zinc may help protect smokers by blocking cadmium. Smokers have higher levels of cadmium in their body, and there may be a link between cadmium and a higher risk for lung cancer. Some laboratory studies have indicated that zinc might help protect against tumor progression. There is no evidence that taking zinc supplements will reduce the risk for lung cancer, however.

A 2003 study reported a lower risk in lung cancer in men and women who were physically active. Both moderate and intensive exercises were associated with protection.

People concerned about radon in their home or area can purchase a test approved by the Environmental Protection Agency. Methods for removing radon include installing a soil suction system. It should be noted, however, that home prevention measures rarely reduce radon levels to zero. Simply sleeping by an open window reduces the risk.

Nonsteroidal anti-inflammatory drugs (NSAIDs) and COX-2 inhibitors (coxibs) both block cyclooxygenase (COX) enzymes. NSAIDs block COX-1 and 2, and coxibs selectively block COX-2. Evidence now strongly suggests that the COX-2 enzyme plays a role in blood vessel growth (angiogenesis) that can feed lung cancers.

NSAIDs. NSAIDs include aspirin, ibuprofen (Advil), and naproxen (Aleve, Naprosyn, Naprelan, Anaprox). These agents inhibit COX-2, but they also target another COX enzyme. Studies are now reporting an association between regular use of aspirin or other NSAIDs and a reduced risk for non-small cell lung cancer.

COX-2 Inhibitors. The COX-2 inhibitors are more recent forms of NSAIDs. Currently, only celecoxib (Celebrex) is still on the market. Rofecoxib (Vioxx) and valdecoxib (Bextra) were withdrawn from the market due to their high risk of causing strokes and heart attacks. Because they target the COX-2 enzyme specifically, researchers are focusing on these drugs for a possible role in treating lung cancer and preventing recurrence.

Diagnostic Tests

Chest X-Rays. In a small percentage of cases, a routine chest x-ray reveals the first signs of lung cancer. Usually, however, symptoms of existing lung cancer, such as coughing, chest pain, and blood in the sputum, will lead to a chest x-ray. If non-small cell lung cancer is present, chest x-rays may show lesions (damaged or abnormal tissue) in the center of the lung, cavities formed by squamous cell carcinoma, or lace-like pattern of cells spreading through the lungs. By the time lung cancer is diagnosed by chest x-rays, however, it has often spread so far that it cannot be surgically cured. Four major studies found no survival benefits in early detection from chest x-rays and sputum screening. Regular screening for lung cancer using x-rays is therefore not currently recommended.

Computed Tomography. Computed tomography (CT), particularly the specific technique called low-dose spiral (or helical) CT, is more effective than x-rays for detecting cancer in patients with suspected lung cancer. It is the standard imaging procedure for determining if and where the cancer has spread (metastasized). Surgeons also use CT scans to evaluate patients before lung surgery.

CT stands for computerized tomography. In this procedure, a thin x-ray beam is rotated around the area of the body to be visualized. Using very complicated mathematical processes called algorithms, the computer is able to generate a 3-D image of a section through the body. CT scans are very detailed.

The use of helical CT for early screening is still controversial. Studies of CT scans in smokers suggest that early screening will detect about 2% of lung cancers, most of these in early stages. In the studies, 62 - 82% of the patients with stage 1A cancer (when the tumor has not spread yet) were still alive at 5 years. Neither study, however, was controlled (compared with other groups, such as non-smokers). The survival figures were likely to be higher than in actual practice.

Click the icon to see an image of a CT scan of the chest.

Evidence regarding the survival benefits of early detection is not clear. Many experts are highly opposed to widespread screening for lung cancer. Some evidence, for example, suggests that lung cancer cells in non-small cell lung cancer are often very aggressive at microscopic levels (before a tumor is formed). If this were true, the cancer would be highly likely to have already spread, long before it was visible with CT scans. Moreover, some studies have found no association between tumor size at the time of diagnosis and survival times. On the other hand, some suspicious areas detected by CT scans may actually be innocent, and these patients might be more likely to die from aggressive treatments than from the disorder itself.

It should also be noted that about 98% of suspicious areas seen on CT scans turn out to be benign. Even after rescreening, many scans will show suspicious areas that turn out to be harmless but will require invasive and expensive biopsies. Additional experience with CT scans, however, may allow experts to better determine which abnormalities are likely to be benign.

High-risk individuals who are still interested in early screening with CT scans should ask their doctor about available clinical trials.

Computed tomography is the standard imaging procedure for determining if and where the cancer has spread (metastasized). Other imaging tests, however, may be useful for staging and tracking lung cancers (staging means finding out how advanced the cancer is).

Positron Emission Tomography. Positron emission tomography (PET), specifically a technique known as FDG/PET, is the most accurate noninvasive test for detecting early lung cancer. It is also the best imaging technique for staging lung cancers, not only those located in the lungs, but also those that have spread, particularly into the space between the two lungs (the mediastinum). With this imaging test, the patient is first injected with a specially formulated liquid sugar (called FDG), and then viewed with a machine that records energy given off by tumor cells.

PET is expensive and not widely available. However, its supporters suggest that it may prevent many unnecessary surgeries by identifying patients whose cancer has advanced past the stage at which surgery is helpful. There is some evidence that FDG/PET scan can detect a metabolic (processing) response to treatments that may help predict the outlook for the patient.

Scintigraphy. Scintigraphy is an imaging procedure in which patients are administered low-level radioactive agents that bind to cancer cells, which then can be tracked by special cameras to reveal the cancer cells' location and intensity. Agents selected are those that can best bind successfully with specific tumor types. For example, a 2001 study of the binding agent 111In-DOTA-LAN demonstrated excellent results in identifying non-small cell lung tumors. This study further suggests the possibility of using such highly-targeted binding agents as lung cancer treatments.

Magnetic Resonance Imaging. Magnetic resonance imaging (MRI), an imaging procedure that uses radio wave energy, is frequently used instead of CT scanning to locate brain and bone metastases that can be associated with lung cancer.

Biopsies of lung tissue are needed to confirm lung cancer. This requires invasive procedures that may vary from simple needle aspiration to chest surgery.

Needle Aspiration. Sometimes, a biopsy specimen is obtained by inserting a needle between the ribs, and then guiding it with the use of computed tomography scans, ultrasound, or fluoroscopy (a device allowing an x-ray view). Specific techniques include transbronchial or transthoracic needle aspiration (TBNA or TTNA) or endoscopic ultrasound-guided needle aspiration (EUS-NA). Their use depends on how much of the area can be observed with less invasive imaging methods. There is a 5 -10% risk for bleeding or collapsed lung with needle aspiration.

Thoracoscopy. Thoracoscopy is usually very effective for diagnosing cancer in the outer areas of the lungs, or those involving the pleura (membrane surrounding the lungs). This is a surgical procedure that uses a fiber-optic tube to view the area:

The procedure requires general anesthesia.
The surgeon passes surgical instruments and a fiber-optic tube through a small incision in the chest. The tube has a camera in it, which allows the surgeon to look at the lungs on a video screen.

Bronchoscopy. To locate cancer that develops in the central areas and major airways of the lung (usually squamous or small cell cancer), bronchoscopy is typically performed. The procedure is done as follows:

The patient is given a local anesthetic, supplementary oxygen, and sedatives.
The doctor inserts a bronchoscope, a hollow flexible tube often containing a fiber-optic light source, into the lower respiratory tract through the nose or mouth.
The tube acts like a telescope into the body, allowing the doctor to see the windpipe and major airways. In a procedure called fluorescence bronchoscopy, the doctor injects the patient with a drug that makes cancer tissue appear red when exposed to laser light from the bronchoscope.
The surgeon removes specimens for biopsy, ideally combining techniques to include cutting tissue, brushings, and a washing process called bronchoalveolar lavage (BAL). BAL involves injecting saline through the bronchoscope into the lung and then immediately suctioning the fluid back through the hollow tube of the bronchoscope; the fluid is then analyzed in the laboratory. Both brushing and washing procedures may be very valuable additions.

Advances in this procedure, such as laser-induced fluorescence endoscopic bronchoscopy, may improve early detection of cancer.

Bronchoscopy is usually very safe, but complications can occur; they include allergic reactions to the sedatives or anesthetics, asthma attacks in susceptible patients, and bleeding. Fever may follow the procedure.

Click the icon to see an image of bronchoscopy procedure.

Click the icon to see an image of a bronchoscope.

Mediastinoscopy. Mediastinoscopy uses a tube inserted between the lungs to locate the appropriate areas for biopsy. It is performed if the physician suspects that cancer has spread to nearby lymph nodes but has not yet metastasized.

Sputum Analysis for Presence of Cancer Cells. Some experts are now recommending an analysis of coughed-up sputum as a useful and cost-effective measure for identifying cancer cells, particularly those located in central areas of the lung. However, although sputum analysis appears to be as accurate as any other screening test currently conducted, it may miss cancers such as adenocarcinoma, which form in mucus-producing cells typically in the outer portion of the lungs. If a sputum analysis does not show cancer cells, but other signs of lung cancer are present, including blood in the sputum and suspicious areas on x-rays, other tests are performed.

Biomarkers. Biologic markers, called biomarkers, are high levels of substances that are released by tumors and indicate the presence of specific cancers. Biomarkers can be found in sputum, blood, and tissue samples. They can include enzymes, hormones, amino-acid compounds, antigens (identified by antibodies that specifically target them), growth factors, and other chemicals. Some biomarkers may prove to reveal the presence of cancer cells before they are evident on CT scans or other imaging tests. For example, genetic mutations, notably K-ras and p53, can now be detected in cells found in sputum, or cells taken during bronchoscopy. Such mutations occur only with cancerous changes and may enable early detection. Other markers that prove to be important for predicting aggressive cancers are high levels of matrix metalloproteinase (MMP9) and vascular endothelial growth factor (VEGF), which are compounds involved with angiogenesis (the process in which blood vessels serving the tumor develop).

As part of the doctor's initial examination, patients may have a pulmonary function test to evaluate lung health and capacity. In addition, since the heart and lungs are often involved in complications following lung cancer surgery, the doctor may be especially interested in taking a complete history of those systems in patients who might need surgery.

Staging Systems

Tests to Determine Cancer Stage. After diagnosing non-small cell lung cancer, the doctor makes treatment choices by determining the cancer's stage (how large the tumor is and how far the cancer has spread). To stage the cancer and determine other aspects of the disease, a number of tests are conducted:

The cancer cells are examined microscopically for size, shape, and other configurations.
Computer tomography (CT), magnetic resonance imaging (MRI), or both, are used to scan the lung and perhaps other locations, such as the liver, upper abdomen, and brain, to determine the extent of the disease.

Physical Examination. A detailed physical examination of the whole body is very important to identify or rule out the spread of cancer to other areas, and to determine the general condition of the patient. For example, questions about dizziness or headaches can help the doctor determine if the cancer has spread to the brain, while bone or joint pain might suggest that the cancer has spread to the bone. The doctor will also look for head and neck symptoms that might reveal the presence of other tumors. Also, according to a 2000 review, the patient's weight loss and ability to function are two very important factors for predicting survival following treatment. Patients who are mobile and have lost less than 10% of their pre-treatment weight tend to have better survival rates.

In lung cancer, the stage of the disease at the time of diagnosis is a major factor in determining how to treat the cancer, and how long the patient can expect to live. In general, survival is longest for patients with very early-stage disease and shortest for patients with very advanced disease that has spread to several regions of the body. Staging is based on the results of physical and surgical examinations, and laboratory and imaging tests, including biopsies.

To determine the stage, medical professionals first categorize each tumor by size and by how far it has extended. This identification method is called the TNM system.

The TNM categories then determine the stage (numbered 0 to IV), indicating how advanced the cancer is.

TNM stands for Tumor, regional lymph Nodes, and Metastasis (cancer spread beyond the original tumor).

T refers to the size and extension of the tumor itself. In TX and T0, the tumor is indicated by cancer cells in sputum or lung samples but cannot be seen. Tis: Carcinoma in situ. The cells are cancerous, but the tumor does not show evidence of spreading. In T1, the tumor is 3 cm or less in size, is still contained in the lung or the membrane covering the lung, and has not reached the main airway.

In T2, the tumor has one or more of the following features:

It is greater than 3 cm
It involves the main airway
It is 2 cm or more away from the ridge (the carina) at the lowest part of the windpipe
It has invaded the pleura
It is associated with collapsed lung tissue (atelectasis) or swelling that blocks part (but not all) of the lung

In T3, a tumor of any size has directly invaded any of the following:

Chest wall
Diaphragm
The membrane covering organs and structures in the chest
The outer wall of the membrane around the heart (pericardium)

In addition, one or more of the following conditions are present:

The tumor is in the main airway, less than 2 cm away from the carina, but is not in the trachea (windpipe).
The tumor is associated with a collapsed lung or swelling that blocks the entire lung.

In T4, the tumor has invaded any of the following:

The area between the lungs (mediastinum)
The heart
The great vessels (the blood vessels that carry blood from the heart)
Carina, trachea, or esophagus
Main portion of the spine

In addition, one or both of the following occurs: separate tumors are present in the same lobe; the tumor is accompanied by an increased amount of fluid between the pleural membrane and the lung.

N followed by a number from 0 to 3 refers to whether the cancer has reached regional (in the area of tumor) lymph nodes. In stage N0, the regional lymph nodes are still cancer-free.

In N1, the cancer has spread to the nearest lymph nodes around the airways, to the hilum (a central zone in the lung where blood and lymph vessels enter), or both. The tumor has extended directly into lymph nodes within the lung. In N2, the cancer has spread to lymph nodes in the middle of the chest that are still next to the affected lung, to the nodes below the carina, or to both regions.

In N3 the cancer has spread to lymph nodes in the middle of the chest that are next to the opposite lung, to the hilum in the opposite lung, to lymph nodes in nearby or opposite muscle tissue, or to lymph nodes above the collar bone.

M Stages refer to metastasis. In M0, metastasis has not occurred.

In M1 distant metastasis has occurred. This includes the presence of a separate tumor in a different lobe.

Staging factors are used to help determine treatment and outlook. The following suggest a more aggressive disease:

The presence of respiratory symptoms
A tumor larger than 3 cm
High numbers of blood vessels in the tumor

Researchers are always looking for more accurate ways to determine a treatment and outlook for lung cancer. For example, some research involves specific biomarkers and related blood vessel development within tumors. These markers might eventually help determine how aggressive a cancer is likely to be, and what the best treatment approach is.

If the cancer is still localized, surgery can produce 5-year survival rates of up to 75% in stage I patients and up to 50% in stage II patients. Unfortunately, very few patients are diagnosed at such early stages. In locally advanced stages, the standard treatment is concurrent radiation and chemotherapy. However, even with this approach average survival times are less than 2 years. Even if an initial tumor has been surgically removed or irradiated, cancer recurrence rates are very high. The risk for recurrence is lower in smokers who quit after treatment.

On an encouraging note, advances in therapies for later stage lung cancer are now offering some hope for improving survival. Still at this time, the mortality rate for lung cancer is still extremely high, and reports of improved response or survival rates using drugs or combinations of therapies do not mean cures. Ultimately, the patient must weigh a diminished quality of life using aggressive treatments against a chance for a modestly prolonged life.

Surgical Procedures

Surgery is performed in the following circumstances:

The surgical removal of an entire lobe or parts of a lung is the primary treatment for eligible patients in early stages of cancer. Recurrence is high after surgery, although the new tumor is often operable.
Some patients with stage IIIA cancer may also benefit from surgery. The intent at this stage is to extend survival time, rather than cure the disease.
Surgery is not out of the question in rare cases of metastasis when the cancer appears in a single operable location, such as the brain.

Unfortunately, lung surgery may be too risky for patients with other lung diseases or serious medical conditions, and because lung cancers tend to occur in smokers over 50, such health problems are likely to be present. Long-term survival rates appear to be better in patients treated at hospitals that perform large numbers of lung cancer surgeries, and when surgeries are performed by thoracic surgeons, who specialize in chest procedures.

The type of surgery depends on the amount of lung or other tissue that needs to be removed.

Wedge Resection or Segmentectomy. Wedge resection and segmentectomy remove only a small part of the lung; consequently, they preserve almost normal breathing function after the operation.

Lobectomy. Removal of one of the lobes of the lung is called lobectomy. The patient's lung function must be adequate before undergoing this procedure. The operation carries an overall mortality rate of 3 - 5%, with older patients having the highest risk.

Click the icon to see an illustrated series detailing surgery to remove diseased lobes of the lung.

Pneumonectomy. Pneumonectomy removes the entire lung. The procedure itself carries a mortality rate of 5 - 8%, with the oldest patients having the greatest risk. In such patients, recurrence almost always occurs.

Surgical advances are allowing a wider range of options, including minimal surgeries for early cancers and surgeries that relieve cancer symptoms in late stages of the disease.

Thoracoscopy. Thoracoscopy, also known as video-assisted thoracic surgery (VATS), is a less-invasive technique that employs a thin tube containing a miniature camera and surgical instruments. It requires much smaller incisions than open surgery and speeds recovery to the point that patients are up within hours. Though the procedure is not appropriate in all cases, it offers significant advantages, especially in older or frail patients. The death and complication rates following VATS are lower than those following conventional surgeries. Pain is reduced, and patients are released from the hospital quicker. Several studies found that the 5-year survival and recurrence rates in patients with stage I NSCLC treated with VATS were comparable to those in patients treated with traditional open chest surgeries.

Laser Surgery. Laser surgeries allow removal of minimal amounts of lung tissue and are proving useful for improving symptoms in stage II and IIIA patients. They may also be beneficial in treating cancers that have spread to the throat, obstructing it.

Photodynamic Therapy. Photodynamic therapy uses bronchoscopy and special laser light beams combined with a light-sensitive drug, called porfimer sodium (Photofrin), to kill cancer cells. The most common side effect is sun sensitivity. Serious side effects include bleeding in the lungs. Photodynamic therapy may be considered for patients in early-stage disease who are not candidates for other surgical procedures. It may also be used to reduce symptoms in late-stage disease.

Cryosurgery. Cryosurgery uses a probe chilled to below freezing to destroy the tumor cells on contact and is being investigated in combination with radiation therapy. It may also be an alternative in early stage cancer for patients who cannot have surgery.

Electric Cauterization. Electric cauterization, the use of electricity to produce heat that destroys tissue, is also under investigation as a treatment for early-stage disease.

Back Surgery. Spinal cord compression is a common cause of pain in patients with advanced lung cancer. Because such patients can live for a year or longer, some research indicates that back surgery followed by radiation therapy can significantly improve the quality of life for many of these patients.

Radiation Treatments

In addition to surgery, radiation is the other primary treatment for early-stage lung cancer. Doctors are also studying the benefits of radiation treatment in advanced lung cancer.

Radical Radiation in Early-Stage Cancer. Radical radiation is used as the sole procedure in stage I and some stage II patients who have adequate lung function but, for medical or other reasons, cannot be treated with surgery. In these cases, the 5-year survival rate is about 20%, and the cancer is likely to recur. Survival rates may be higher or lower, depending on the tumor size. In general, treatment with radiation therapy alone shows less benefit with larger tumors. A 2002 analysis suggested that the use of radiotherapy after surgery in patients whose tumors had been completely removed might be associated with reduced survival rates. Nevertheless, a recent study confirmed earlier results that show that radiation therapy by itself is as effective as surgery in patients who are unable or unwilling to have surgery for early stage non-small cell lung cancer.

Combined Treatments for Improving Survival in Advanced Cancer. Radiation is also being investigated in various combinations with chemotherapy, surgery, or both. At this time, concurrent radiation treatment plus platinum-based chemotherapy may extend survival times in advanced lung cancer. Other combinations are showing promise.

Palliative Radiation. Doctors use palliative radiation to shrink tumors and reduce pain and symptoms. Palliative radiation is appropriate for patients with advanced disease and poor lung functions, or in those with metastasized cancer. In up to 85% of patients with advanced disease, palliative radiation therapy helps relieve pain, shortness of breath, the superior vena cava syndrome, coughing up blood, and symptoms caused by brain metastases. Radiation, in these cases, is not generally used with the intention of reducing mortality rates, although it may increase survival in some patients, such as those with excellent lung function whose tumors are small.

Delaying radiation therapy until symptoms develop does not appear to reduce survival times or impair quality of life compared to starting it right away, in patients with minimal or no symptoms.

Radiation Therapy in Metastasis to the Brain. Radiation is the primary treatment when cancer has spread to the brain unless the cancer is small enough to be treated surgically. When radiation is used, a technique called stereotactic radiosurgery may be used to deliver powerful, highly targeted radiation to specific areas in the brain. Some trials are investigating using radiation to the head to prevent metastasis to the brain.

The goal of radiation treatment is to administer doses as high as possible to kill as many cancer cells as possible, without destroying surrounding healthy tissues or causing a dangerous reaction. Doctors may try different procedures for the same patient. The exact radiation procedure depends on the site of the cancer or how far it has spread:

External-Beam Radiation. External-beam radiation therapy focuses a beam of radiation directly on the tumor. It is generally used for metastasized cancer.
Brachytherapy. Brachytherapy involved the implantation of radioactive seeds through thin tubes directly into the cancer sites. Brachytherapy may be used for lung cancers that have spread to the throat and caused obstruction. High-dose-rate brachytherapy may also have some value for patients with inoperable tumors in the central region of the lung.

Hyperfractionated radiotherapy gives smaller than standard doses a number of times a day (usually two or three). This allows doctors to use a higher cumulative dose over the whole course of treatment. It is not as useful as therapy by itself, but should be combined with chemotherapy to have any survival benefits.

Hyperfractionated Accelerated Radiotherapy. Continuous hyperfractionated accelerated radiotherapy (CHART) administers multiple doses per day but uses standard doses. This allows the total dose of radiation to be administered over a shorter time period than the standard 6 weeks. CHART is proving to extend survival rates of patients with localized cancer over that of standard radiotherapy or non-accelerated hyperfractionated radiation. It can cause severe swallowing problems. A modification in which treatment is suspended for 2 days out of 7 may help reduce this effect.

Three-dimensional (3-D) conformal radiotherapy delivers external-beam radiation designed to closely match the specific targeted organs or tissues. This allows significantly higher doses to attack the cancer while reducing the risk to healthy cells. In a 2003 report, 3-year survival rates in stage IIIA patients were nearly 60%, and nearly half the patients experienced no side effects.

Stereotactic body radiotherapy, an advance on conformal radiation, uses a body frame and an abdominal press to immobilize the patient's body and limit breath movement. This allows a more accurate delivery of high-energy radiation. The technique is still investigational.

Radiation can have significant side effects when used as part of intensive treatments, such as hyperfractionated radiotherapy or radiotherapy in combination with chemotherapy. Among the most serious problems is severe inflammation in the esophagus (esophagitis) or the lungs (pneumonitis). Infection is also a danger.

The use of targeted approaches, such as conformal radiotherapy, may help reduce these complications. Investigators are also studying drugs, notably amifostine, which appear to help reduce throat and lung inflammation caused by radiation, without reducing its cancer-fighting effects.

Treatment Options by Stages

In the occult stage (TX, N0, M0), cancer cells are found in a sample of a patient's coughed-up sputum, but no cancer cells have yet been detected in the lung.

Treatment Options. Surgical removal of the tumor, if one can be located, allows identification of its stage and often results in cure.

Stage 0 or carcinoma in situ (Tis, N0, M0) are noninvasive cancers and only a few layers of cancer cells are detected within one local area. The cancer has not grown through to the top lining in the lung and can be surgically removed. There is a high risk for development of a second tumor, however.

Treatment Options:

Surgery, often a limited procedure, where only part of a lobe is removed from the lung.
In patients who cannot be treated surgically, consider photodynamic therapy, cryotherapy, or brachytherapy.

In stage I, the cancer has reached higher layers of the lung but has not spread into the lymph nodes or beyond the lung.

General Treatment Options. The primary treatment is surgery, such as lobectomy (removal of a whole lobe), if possible. Patients with poor lung function should undergo partial lobectomy, if possible. Radiation treatments may be appropriate and beneficial for patients who cannot have surgery. It is not clear if early-stage lung cancer patients, who have radiation or chemotherapy in addition to surgery, have higher survival rates. A 2002 analysis suggested that the use of radiotherapy after surgery in patients whose tumors had been completely removed might be associated with reduced survival rates. An analysis of studies using chemotherapy in addition to surgery or radiotherapy, however, indicated benefits in survival. The overall 5-year survival rates for early stage-cancer are in the range of 30 - 50%. Patients should consider clinical trials for prevention of recurring (returning) cancer after the initial treatment. The risk for recurrence is highest in patients who continue to smoke.

Stage IA (T1, N0, M0). The 5-year survival rates for stage IA patients after successful treatment can be as high as 80%. Treatment options are:
- Lobectomy or sometimes pneumonectomy (removal of one lung)
- Wedge or segment removal, particularly in patients with poor lung function who cannot withstand lobectomy
- Radiation in selected patients whose condition is inoperable (for example, frail patients with T1 tumors); 5-year survival rates can be equal to those with surgery, between 32 - 60%
- Clinical trials of adjuvant chemotherapy following surgery

Stage 1B (T2, N0, M0). Stage IB survival rates after treatment can be better than 60%. Treatment options are:
- Lobectomy or sometimes pneumonectomy; wedge or segment removal, particularly patients with poor lung function
- Clinical trials of chemotherapy following surgery
- Clinical trials of chemotherapy before surgery (induction therapy; studies are promising)
- Clinical trials for radiation treatments in selected patients whose condition is inoperable
- Clinical trials of chemotherapy before, after, or during radiation treatments

In stage II the cancer cells have spread to nearby lymph nodes.

General Treatment Options. Surgery, usually removal of a lobe (lobectomy) or one lung (pneumonectomy), is the treatment of choice. Five-year survival rates associated with stage II surgery can vary. A 2000 review of existing research places the numbers as high as 40 - 50%, but notes that they can drop to 25% and below if the cancer has spread beyond the immediate lymph nodes.

Patients whose cancer is inoperable may consider radiation treatments. In patients who can complete treatment, 5-year survival rates average 20 - 30%, with higher rates for stage IIA. Patients should consider clinical trials for prevention of recurring cancer after primary treatment. To date, however, supplementing surgical treatment with radiation or chemotherapy does not appear to prolong survival rates.

Stage IIA (T1, N1, M0). Survival rates can be as high as 60%. Treatment options are:
- Surgery
- Radiation
- Clinical trials of chemotherapy following surgery
- Clinical trials of chemotherapy before, after, or during radiation treatments
- Clinical trials of chemotherapy to reduce tumor size before surgery (induction therapy)
Stage IIB (T2, N1, M0) or (T3, N0, M0). Survival rates can be over 40%. Treatment options are:
- Surgery
- Radiation
- Clinical trials of chemotherapy following surgery
- Clinical trials of chemotherapy before surgery (induction therapy)
- Clinical trials of chemotherapy before, after, or given at the same time as radiation treatments

In stage III, the cancer cells have spread beyond the lung to the chest wall, diaphragm, or further lymph nodes, such as those in the neck.

General Treatment Options. Generally, the treatment of choice for stage III tumors is radiation and sometimes surgery, chemotherapy, or combinations of all three.

Combination approaches may be significantly more effective than single treatments. For example, of particular interest is a treatment approach that starts with chemotherapy and radiation, given at the same time, followed by surgery. In one study, 5-year survival in stage III patients treated this way was nearly 50%.

Stage IIIA (T1, N2, M0) or (T2, N2, M0) or (T3, N1, M0) or (T3, N2, M0).
- Surgery, if the tumor and affected lymph nodes can be completely removed. Consider platinum-based chemotherapy or radiation therapy after surgery.
- Radiation treatment plus platinum-based chemotherapy, given at the same time, is an option for those in otherwise good health. This regimen should be followed by surgery, if possible.
- Consider clinical trials using advanced radiation techniques, including continuous hyperfractionated accelerated radiation, or 3-D conformal radiation.
- Consider other clinical trials, including those of various combination treatments, preventive radiation therapy to the brain, and new second-line drugs.
Stage IIIB (Any T, N3, M0) or (T4, Any N, M0). Some patients may consider surgery if there is no lymph node involvement (T4, N0), and tumor can be removed. Surgery is not an option for other patients with stage IIIB cancer. Treatment options are:
- Radiation alone, usually for symptom control; it may improve survival in certain patients, such as those with lymph node involvement above the collar bone
- Chemotherapy alone
- Concurrent (given at the same time) cisplatin-based chemotherapy plus radiation, sometimes followed by surgery if possible
- Clinical trials using induction chemotherapy alone to shrink tumors, which may then be treated with surgery or radiation
- Clinical trials using advanced radiation techniques, including continuous hyperfractionated accelerated radiation, or 3-D conformal radiation
- Other clinical trials, including those of various combination treatments, preventive radiation therapy to the brain, and new second-line drugs

In stage IV (any T, any N, M1), the cancer has spread (metastasized) to other parts of the body.

Treatment Options are:

Combination of two- or three-drug chemotherapies that include platinum-based drugs and newer agents; the best patient candidates are those in otherwise good health, who have a limited number of distant metastasized sites. Chemotherapy is not recommended for patients who are too ill
External-beam radiation for symptom relief
Paclitaxel or gemcitabine as a single medication
Other clinical trials
If metastasized cancer involves only one or two areas in the brain, it may respond to surgery followed by radiation to the brain

Recurring or additional new tumors occur, usually in the lung again, in half of treated patients. Research shows that a single tumor in the lung is more often a new tumor that, in many cases, may be operable.

Treatment Options are:

Radiation for symptom control
Chemotherapy with or without bevacisumab (Avastin)
If the cancer spread to only one site in the brain, it may respond to surgery, followed by whole-brain radiation. Extended disease-free survival is possible. If the brain tumor is not operable, it is treated with radiation. Even if cancer returns in the brain (in 50% of cases), treating it again is possible in many patients, if the disease has not spread elsewhere
Laser therapy or interstitial radiation for tumors inside the airways
Stereotactic radiosurgery (in a few selected patients)

Chemotherapy Treatments

Chemotherapy is the use of drugs given by mouth or by injection to destroy cancer cells that may have spread beyond the tumor. Until recently, there has been some doubt about the effectiveness of chemotherapy for lung cancer. A major 2002 analysis of 52 trials supported its use, particularly with platinum-based regimens, and with the use of supportive care.

Chemotherapy in early stages: Chemotherapy is proving to be beneficial in many patients as an additional (adjuvant) treatment with surgery or radiation.
Chemotherapy in advanced disease: Chemotherapy may be used as first-line treatment in patients with inoperable or metastasized lung cancer. It is typically used in late stages to reduce symptoms and, in some cases, extend survival. Since 2006, the combination of bevacizumab (Avastin, a monoclonal antibody) and platinum-based chemotherapy is also a first line treatment choice for such patients, if the cancer is the non-squamous type

Powerful platinum compounds, either cisplatin (Platinol) or carboplatin (Paraplatin), are the basis for most chemotherapy regimens. Two-drug combinations, with one drug being a platinum-based agent, are currently the preferred regimens. Reasonable combinations include paclitaxel (Taxol) and carboplatin or cisplatin. This regimen can also include gemcitabine, docetaxel, or vinblastine or its derivative (vindesine or vinorelbine). There does not seem to be any significant differences in effectiveness among them. Gemcitabine and vinorelbine combination might be a good option for patients who cannot tolerate platinum compounds. Chemotherapy for lung cancer may have reached its peak. Still, investigative chemotherapeutic drugs may yet improve response. Many experts are pinning their hope on agents called biologic response modifiers, such as gefitinib (Iressa) or LY900003 (Affinitak). To date, however, they have not achieved better results than standard platinum-based chemotherapies. Gefitinib (Iressa), a second-line therapy for non-small cell lung cancer (NSCLC), is now available only for a limited group of patients. These patients have benefited from gefitinib in the past, or they are enrolled in a clinical study with the drug. While this medicine initially showed great promise in clinical trials, results from a newer study failed to show that it prolonged survival in advanced lung cancer patients who failed other treatments.

If you are currently taking gefitinib, do not stop taking it without talking to your doctor.

Erlotinib (Tarceva) is in the same medication class as gefitinib. It is approved for patients with locally advanced or metastatic NSCLC, who have failed one type of chemotherapy treatment in the past (it is a second-line treatment). Unlike gefitinib, erlotinib shows survival and progression-free benefits compared to placebo. However, it should not be combined with platinum-based chemotherapy.

Chemotherapy treatments are usually performed in an outpatient setting and in regular cycles for several months. How many chemotherapy cycles to administer in late-stage cancers, the timing of those cycles, and the sequences of the drugs are still matters of investigation. For instance, research suggests that a three- or four-course cycle may achieve the same survival times and better quality of life than the standard of six or more course cycles. Changing even one day in a drug sequence can sometimes significantly affect outcome. Such fine-tuning of chemotherapy regimens is likely to have the most effect on patients with advanced-stage disease, which requires more tailored treatment than early-stage disease.

Treatment for lung cancer depends on the type of cancer and the stage of the disease. Chemotherapy is a form of treatment for lung cancer that may cure, shrink, or keep the cancer from spreading.

Side effects of chemotherapy treatments are common, and they are more severe with higher doses. Side effects increase over the course of treatment. Some trials suggest that they can be reduced by giving the drugs for shorter durations, without loss of cancer-killing effects. Common side effects include the following:

Diarrhea
Temporary hair loss
Weight loss
Fatigue
Depression
Nausea and vomiting: Drugs known as serotonin antagonists, especially ondansetron (Zofran), can relieve these two side effects. Serotonin antagonists work well in nearly all patients given moderate drugs, and in most patients who take drugs that are more powerful. In one study, a combination of dexamethasone (a steroid) with ondansetron, taken within 24 hours of chemotherapy, achieved either a major or complete reduction in nausea and vomiting.
Anemia: Anemia, an abnormally low number of red blood cells, is common in lung cancer. Treatments include transfusions or injections of erythropoietin, an agent that causes more red blood cell production. Erythropoietin is available as epoetin alfa (Epogen, Procrit) and darbepoetin alfa (Aranesp), which requires fewer injections. These agents improve well-being and quality of life. Trials are in progress to determine if they may have survival benefits as well.

These side effects are nearly always temporary. Most patients are able to continue with normal activities for all but perhaps 1 or 2 days per month.

Serious complications of chemotherapy can also occur and may vary depending on the specific drugs. They include the following:

Increased chance for infection from suppression of the immune system.
Severe drops in white blood cells (neutropenia): Certain chemotherapy drugs, such as taxanes, pose a higher risk for this complication than other drugs. White blood cell count can improve with the addition of a type of drug called granulocyte colony-stimulating factor (filgrastim and lenograstim).
Liver and kidney damage: Amifostine (Ethyol) reduces the risk for kidney damage in patients taking repeated regimens of cisplatin-based therapy. It is also a radioprotector; that is, it helps prevent severe effects in the esophagus from radiotherapy, with or without chemotherapy.
Abnormal blood clotting (thrombocytopenia).
Allergic reaction, particularly to platinum-based agents: A simple skin test is under investigation that may identify people with a potential allergic response.

Second-line chemotherapy is used for patients whose cancers have recurred after first-line chemotherapy. Some experts believe that the longer survival rates for advanced lung cancer seen for the past 5 years may be due to these drugs. Because platinum-based agents are most often used first, they are not beneficial for second-line therapy. The following are commonly used second-line agents.

Docetaxel (Taxotere). Docetaxel is the drug of choice at this time for cancers that do not respond to initial chemotherapy. Studies have reported that it achieves longer survival times than supportive care alone. It is usually given every 21 days. This regimen causes more side effects than pemetrexed, the newer major second-line drug. Weekly doses of docetaxel are effective and less toxic than the 3-week schedule. It is not clear if survival rates are comparable to those of pemetrexed with that schedule, however.

Pemetrexed (Alimta). Pemetrexed, known as an anti-folate, is another promising new agent for second-line therapy and possibly for first-line treatment as well. The drug targets a number of enzymes that play a role in how cancer cells increase. Some research suggests that it is as effective as docetaxel. Pemetrexed does have some serious toxic effects, but they can be significantly reduced with folic acid and vitamin B12 supplements. It is then less toxic than docetaxel, when docetaxel is given every 21 days, but not when it is given weekly.

Gefitinib (Iressa) and Other Tyrosine Kinase Inhibitors. Much research is focusing on drugs that block small molecules involved with the growth of blood vessels that feed the tumor (a process called angiogenesis). Compounds called growth factors, which may be important in cancer cell production, control the growth of these new blood vessels. Researchers, then, are interested in medications that literally turn off these growth factors or their receptors, such as epidermal growth factor receptor (EGFR). In so doing, the agents may be able to cut off cancer's lifeblood. Gefitinib and erlotinib are angiogenesis inhibitors that target receptors of an epidermal growth factor called tyrosine kinase. Interestingly, studies are finding that NSCLC tumors in people who have never smoked have a much higher rate of EGFR mutations. This helps to explain why gefitinib and erlotinib are more effective in treating NSCLC in people who have never smoked.

Gefitinib (Iressa) was approved in 2003 as a second-line therapy for non-small cell lung cancer. Many patients report significant improvement in symptoms and quality of life, and the drug initially showed great promise. In one study, gefitinib reduced tumor size by 50% in about 10% of the patients. However, recent large-scale clinical trial results have failed to confirm any survival advantage for most patients. At this time, gefitinib is available only for patients who have benefited from it in the past.
Erlotinib (Tarceva) was approved as a single agent second-line therapy in November 2004. Study results show that the drug prolonged survival by several more months than placebo (6.7 versus 4.7 months). Erlotinib is administered orally and has very low toxicity (rash and diarrhea are common).

Chemotherapy Following Surgery (Adjuvant Chemotherapy). Chemotherapy is being evaluated in combination with surgery, radiation therapy, or both. Fairly strong evidence is now supporting the use of platinum-based chemotherapy as adjuvant treatment after surgery in patients with lung cancers in stages Ib-IIIa, with some research indicating a 5% improvement in five-year survival rates. Not all studies confirm survival benefits, however, and trials are ongoing.

Chemotherapy before Surgery (Induction Chemotherapy). Some researchers are testing induction chemotherapy, which is used to shrink potentially operable tumors before surgery. Studies have been mixed in reporting any survival benefits in patients with advanced lung cancer.

Combined and Multi-Modal Therapy. In stage III cancers, investigators are researching very intensive treatments that use two or more combinations of chemotherapy, radiation, and surgery.

For example, radiation plus chemotherapy may be helpful in patients whose tumors are surgically removable.

In inoperable lung cancer, combining radiation with chemotherapy is proving to extend the time to recurrence, the overall duration of survival, or both, compared to radiation alone. Evidence also suggests that giving radiation treatments at the same time as chemotherapy (instead of in separate cycles) improves 5-year survival rates, compared to a sequential approach (separate cycles following each other). Chemotherapy and radiation treatments given at the same time are more toxic, however.

Other approaches use even more intensive multi-modal therapy. For example, some trials use radiation therapy with chemotherapy, followed by surgery. Patients are then sometimes given additional chemotherapy or radiation. In other promising regimens, patents are given concurrent radiation and chemotherapy followed by chemotherapy alone. Such approaches are very toxic but appear to improve survival in selected patients.

Severe inflammation in the esophagus is the most common severe side effect of the radiation and chemotherapy combination. There is also a very high risk of serious infections, including pneumonia, herpes zoster, and cytomegalovirus. Long-term antibiotic therapy may be needed.

Although patients over 70 may suffer more from toxic effects than younger patients, studies now suggest that they can achieve survival rates with combined treatments that are equal to those in younger patients.

There are many painkilling medications available. Research shows that aggressive pain relief can help patients manage cancer treatment symptoms (in addition to pain) better. For example, a 2001 study suggested that reducing pain in elderly cancer patients markedly lowered their fatigue levels, and improved other symptoms as well.

Opioids are the most potent painkillers. The correct use of these strong medications is very important for reaching acceptable pain relief, and preventing a toxic response. For example, the long-lasting version of oxycodone (OxyContin) must be swallowed whole; chewing, inhaling, or injecting it can create a deadly overdose.

Investigative Agents

According to a 2001 article, of the nearly 500 cancer drugs currently in development, 58 of them (about 13%) are aimed at fighting lung cancer. Only the number of breast cancer drugs exceeded that percentage. Unfortunately, none to date have shown any real benefit in terms of patient survival. However, some drugs are showing promise, and at this time, these agents are the best hope for improving lung cancer survival rates.

Monoclonal antibodies (MAbs) are genetically designed immune factors. MAbs mark foreign compounds called antigens for attack by the immune system. Trastuzumab (Herceptin) and cetuximab (Erbitux) are MAbs under investigation for lung cancer. Bevacizumab (Avastin) was approved in October 2006 as a first-line treatment (in combination with carboplatin and paclitaxel) for inoperable, locally advanced, metastatic, or recurrent non-squamous, non-small cell lung cancer.

All three of these MAbs block epidermal growth factor. These agents are of particular interest for patients who have cancers that produce too much of the protein called HER2. These agents show great promise in combination with chemotherapies and newer drugs, such as the tyrosine kinase inhibitors. For example, the disease-free survival time in patients with advanced NSCLC is longer when adding bevacizumab to platinum-based chemotherapy.

Antisense oligonucleotides are drugs being used to block molecules that result in too many cells that cause cancers. LY900003 (Affinitak), for example, targets an enzyme called PKC-alpha, which promotes tumor growth. Early studies with Affinitak showed some promising results. However, a 2003 study found no difference in survival when patients received Affinitak in combination with platinum-based chemotherapy, compared to patients receiving chemotherapy alone.

Genasense (G3139, oblimersen) blocks Bcl-2. Bcl-2 is a protein that is expressed in abnormally high amounts in some cancers. This antisense drug is also under investigation.

Advexin, a genetic therapy that contains the p53 tumor-suppressor gene, is showing promise. In one early study, 60% of patients experienced partial or total tumor shrinkage when the agent was used in combination with radiation therapy. A 2006 study in Japan found that out of 13 patients with advanced NSCLC receiving Advexin, 10 had stabilized. Three of the stabilized patients remained stable for over 9 months. One patient had a partial response to Advexin. The only side effect of the multiple doses given was a passing fever that disappeared within 24 hours. Advexin is in Phase II clinical trials for NSCLC.

Vaccines use inactivated genetic materials from cancer cells, such as defective p53 or ras genes, to cause a highly targeted immune response to attack the cancer.

Retinoids are vitamin A-like antioxidant chemicals that help repair cell damage and appear to support growth of lung cells. A number of retinoid-like agents (retinal palmitate, TAC-101, 23-cis-retinoic acid, N-acetyl-cysteine) are being studied for the treatment or prevention of lung cancer.

Resources

www.cancer.gov -- National Cancer Institute
www.cancer.org -- American Cancer Society
www.cancercare.org -- Cancer Care
www.lungusa.org -- The American Lung Association
www.asco.org -- American Society of Clinical Oncology
www.alcase.org -- Alliance for Lung Cancer
www.lungcancer.org -- Joint project of Cancer Care and the Oncology Nursing Society
www.nccn.org -- National Comprehensive Cancer Network
www.lungcanceronline.org -- Lung cancer information
www.epa.gov/iaq/radon -- National radon information
www.clinicaltrials.gov -- Find clinical trials
www.cancer.gov/clinicaltrials -- Find clinical trials

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Review Date:
8/3/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

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