Prostate cancer

Highlights

New Guidelines for Localized Prostate Cancer

In 2007, the American Urological Association (AUA) released updated guidelines for treatment of localized prostate cancer. The guidelines recommend that:

• Patients should be classified as low, intermediate, or high risk, depending on their PSA levels, cancer stage, and tumor aggressiveness.
• Doctors need to consider patients’ personal preferences and quality of life concerns as well as their clinical status.
• Standard treatment options include active surveillance (watchful waiting), surgery, or radiation therapy. Initial androgen deprivation therapy (hormone therapy) is seldom recommended for localized prostate cancer.

New Guidelines for Androgen Deprivation Therapy

• The American Society of Clinical Oncology (ASCO) 2007 guidelines recommend that doctors delay androgen deprivation therapy for advanced prostate cancer until patients develop symptoms. When treatment is started, ASCO recommends either removal of both testicles (orchiectomy) or luteinizing hormone releasing hormone (LHRH) drug treatment.
• Androgen deprivation therapy can increase the risks for heart disease death and diabetes, according to a 2006 Journal of Clinical Oncology study.

Diagnosis

• Experts do not recommend prostate specific antigen (PSA) tests for men over age 70, yet many of these men continue to receive unnecessary tests, indicates a 2006 Journal of the American Medical Association study.
• A new investigational test for early prostate cancer antigen-2 (EPCA-2) may be more accurate than the PSA test and may eventually replace it, suggests a 2007 study in Urology.

Genetic Research

Researchers have identified a set of genetic variations that may account for about 68% of prostate cancer cases in African-American men. Scientists hope that further investigation of this chromosomal region may help in developing genetic tests for prostate cancer.

Introduction

Prostate cancer is a malignant tumor that arises in the prostate gland. As with any cancer, if it is advanced or left untreated in early stages, it can eventually spread through the blood and lymph fluid to other organs. Fortunately, prostate cancer tends to be slow growing compared to other cancers. As many as 90% of all prostate cancers remain dormant and clinically unimportant for decades. This high incidence of latent or incidental malignancy is unique to the prostate gland. Most older men eventually develop at least microscopic evidence of prostate cancer, but it often grows so slowly that, as one specialist has written, many men with prostate cancer "die with it, rather than from it."

The prostate gland is an organ that surrounds the urinary urethra in men. It secretes fluid which mixes with sperm to make semen.

Male hormones (androgens) play major roles in the development of prostate cancer. Some research, for example, reports a higher risk with increasing testosterone and a lower risk with increasing estrogen levels. Dihydrotestosterone (DHT) is the principal male hormone in the prostate gland. It affects the size of the prostate gland itself and may play a role in prostate cancer. Nevertheless, researchers have not yet fully clarified the specific mechanisms that may be important in the development of this disease. Most likely, genetic mutations affecting androgens trigger the process. Certain growth hormones, such as insulin-like growth factor-I, are unrelated to testosterone and may increase the risk for prostate cancer.

Click the icon to see an image of the male reproductive anatomy.

Prognosis

Prostate cancer is the most common male cancer in the U.S. Only lung cancer causes more cancer deaths in American men. The lifetime probability of developing prostate cancer is about 16%. Each year, approximately 218,890 men in the United States will be diagnosed with prostate cancer, and about 27,050 will die from the disease. According to the American Cancer Society, 5-year survival rates for all stages of prostate cancer have increased during the past 20 years from 67% to nearly 100%.

A survival rate indicates the percentage of patients who live a specific number of years after the cancer is diagnosed. For prostate cancer, the 10-year survival rate is 93% and the 15-year survival rate is 77%. After 15 years, survival rates stabilize. A 2006 study in the Journal of the American Medical Association found that men who are diagnosed with low-grade prostate cancers have a minimal risk of dying from prostate cancer up to 20 years after diagnosis. However, men diagnosed with more severe forms of prostate cancer have a higher risk of dying within 10 years.

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

Because so many prostate tumors are low-grade and slow growing, survival rates are excellent when prostate cancer is detected in its early stages. Cure rates can be as high as 98% in some cases.

Click the icon to see an image of the pelvic lymph nodes.

Locally Advanced. If the disease is at the locally-advanced stage, in which it has spread beyond the prostate but only to nearby regions, it is more difficult to cure, but survival rates can be prolonged for years in many men. (When cancer has metastasized to the pelvic lymph nodes, the outlook is worse than if it has spread to other areas.)

Metastasized Cancer. If prostate cancer has spread to distant organs (metastasized), average survival time is 1 - 3 years, but some of these patients may live longer or die of other causes.

If cancer recurs after initial treatment for early-stage tumors, it is still potentially curable if it is contained within the prostate, although in most cases the cancer has spread. Hormone treatments for such recurring cancers can often prolong survival for years, although the cancer almost always returns again.

Risk Factors

The major risk factors for prostate cancer include genetic, dietary, and environmental factors that affect male hormones (androgens) and make a man more susceptible to this cancer.

Prostate cancer occurs almost exclusively in men over age 40 and most often after age 50. It is estimated that by age 70, about 65% of men have at least microscopic evidence of prostate cancers. Fortunately, the cancer is often very slow growing and older men with the cancer nearly always die of something else.

Heredity plays a role in some types of prostate cancers. Men with a family history of the disease have a higher risk of developing prostate cancer. Having one family member with prostate cancer doubles a man's own risk, and having three family members increases risk by 11-fold.

In 1998, scientists discovered a gene, located on chromosome 1, which may be involved in 1 in 500 cases of prostate cancer. They named this gene HPC1. (HPC stands for “hereditary prostate cancer.”) In 2005, scientists announced another major breakthrough in understanding the genetic components of prostate cancer. Research published in Science suggested that, in some cases, prostate cancer occurs when a specific set of genes merge. The genes are part of the ETS gene family and include ETV1, ETV4, and ERG.

In 2007, three separate studies published in Nature Genetics focused on DNA variations located on chromosome 8 in the 8q24 region. The research suggested that men who carry these genetic variations have a substantially increased risk of developing prostate cancer. The DNA variations may be associated with as many as 32% of prostate cancers in Caucasian men and 68% of prostate cancer cases in African-American men.

Doctors hope that future research will help develop genetic tests to identify men most at risk and, eventually, targeted drug therapy for prostate cancer.

A gene is a short segment of DNA which is interpreted by the body as a plan or template for building a specific protein. Genes reside within long strands of DNA which in turn make up the chromosomes.

African-American men have the world's highest risk for prostate cancer, more than 50% higher than the risk for Caucasian males. The disease is also more lethal among African-Americans. Men who live in Asia have lower risks for prostate cancer, but their risk increases if they move to North America. This indicates that there are unknown environmental or dietary factors that can alter a man's underlying genetic risk of developing this disease.

Socioeconomic Issues. The higher mortality rates in African-American men may be partly due to socioeconomic factors, such as lack of insurance, irregular screening and a late diagnosis, and unequal access to health care.

Dietary Factors. Dietary factors may play some small role in the higher risk in African-American men. This is suggested by the fact that prostate cancer is rare in many parts of Africa.

Biologic Factors. Evidence suggests that African-American and Asian men have certain genetic factors that may affect male hormones differently and may help account in part for the higher risk in the first group and the lower risk in the second.

Higher PSA Levels. African-American men also tend to have higher PSA levels than Caucasians. They are overdiagnosed with prostate cancer by 37% compared to 15% in Caucasians using PSA screening tests.

Chemicals. The relationship between prostate cancer and chemical exposure is controversial. Men whose work involves heavy labor and those exposed to certain metals and chemicals, including cadmium, dimethylformamide, and acrylonitrile, may be at higher risk for prostate cancer. Some studies have indicated that farmers might be at higher risk.

A 2001 study concluded that certain leisure activities may expose men to the same chemicals as those that pose a possible danger in the industrial setting. These chemicals included:

• Home or furniture maintenance
• Painting, stripping, or varnishing furniture
• Activities that involved exposure to lubricating oils or greases, metal dust, or pesticides or garden sprays

Scientists think that specific genes that affect the body's response to viruses may be associated with certain types of prostate cancer. Some theories suggest that there may be a relationship between prostate cancer and infections, such as herpes virus, human papillomavirus, and cytomegalovirus. In 2006, scientists identified a new virus, XMRV, which is 30 times more common in men with prostate cancer who have a genetic mutation with the HPC1 gene. Scientists know that men who have the HPC1 genetic mutation are more likely to get prostate cancer. This new research suggests that the genetic mutation may make them more vulnerable to a virus that causes the cancer. Researchers will continue to investigate XMRV and other possible infectious causes of prostate cancer.

Obesity. Obesity may increase the risk for prostate cancer, particularly more aggressive forms of the disease. Obesity may also make prostate cancer more difficult to diagnose. A 2005 study found that overweight and obese men were more likely to be diagnosed with advanced prostate cancer and to die of the disease than normal-weight men.

Nonmelanoma Skin Cancers and Sunlight. Some studies report that patients with prostate cancer and a history of nonmelanoma skin may have a higher risk for a poorer outlook. Such skin cancers are highly associated with exposure to sunlight. However, sunlight triggers production of vitamin D in the body, which research indicates may help protect against prostate cancer. Prostate cancer rates are, in fact, lower in southern, sunny regions.

Vasectomy. Because testosterone levels remain higher for a longer period in men who had vasectomy, experts have theorized that such men have a greater chance for developing the cancer. While some studies have suggested a higher risk with vasectomy, other studies have reported no higher danger. A rigorous 2002 study from New Zealand, for example, which has the highest vasectomy rates in the world, found no increased risk of prostate cancer from the procedure, even 25 years after the operation. A 2002 study in California, in fact, reported a lower risk for prostate cancer in men who had had vasectomies. It is possible that the higher rates reported in earlier studies may have been due to earlier prostate screening in men who have had vasectomies. Indeed, one study reported that about 25% of doctors screened men with vasectomies earlier for prostate cancer than those without the operation. [See In-Depth Report #37: Vasectomy.]

Click the icon to see an illustrated series detailing a vasectomy.

Click the icon to see an animation on vasectomy.

A Western lifestyle is associated with prostate cancer, so obesity, high-meat intake, and dietary fats have been intensively studied. Results have been inconsistent, however. Certain factors, such as cancer-causing compounds in well-cooked meat or high-calorie intake, may help explain the associations between such dietary factors and cancer risk.

Click the icon to see an image on different types of weight gain.

Fats. Some studies have found an association between high fat-intake and prostate cancer. This association may be explained by other suspected dietary factors for prostate cancer, such as high-calorie diet, high meat intake, and calcium (found in dairy products), all of which are associated with fat intake. The effects of specific fatty acids (compounds that make up fats) may also help clarify the role of fats in prostate cancer. The omega-3 fatty acids in fish (EPA and DHA) and the omega-3 fatty acids found in certain vegetables (ALA) can all protect the heart, but they may have different effects on the prostate.

• Marine Omega-3 Fatty Acids. Research indicates that docosahexanoic acid (DHA) and eicosapentaneoic acid (EPA), the omega-3 fatty acids found in fish, may be protective against prostate cancer. Some studies have reported a lower risk for prostate cancer in men who ate fish frequently (two or more times a week).
• Alpha-Linolenic Acid. On the other hand, some research has indicated that alpha-linolenic acid (ALA), the omega-3 fatty acid found in certain plants and nuts (flaxseed, canola, walnuts), may increase the risk of prostate cancer. However, some studies suggest that flaxseed, a plant food that is also rich in omega-3 fatty acids, may help slow the growth of prostate tumors.

Meat and High-Temperature Cooking. Some evidence suggests that a high intake of red meat raises the risk for prostate cancer. Because red meat is high in saturated fat, such findings may explain the inconsistencies found in studies that simply look at fat content as a risk for prostate cancer. High-temperature cooking (grilling, broiling, or pan-frying) of meat or poultry has been specifically associated with increased risk for cancer in some studies. Over-cooking meat increases the amount of compounds called heterocyclic amines, which has been associated with cancerous changes in general and prostate cancer in particular, at least in some studies. Cooking meats in liquid does not appear to increase these compounds. As with all dietary studies, some have observed no association between high intake of well-cooked meat and prostate cancer.

Vegetarian Diet. Small studies suggest that a vegetarian diet may be protective. Specific foods may be especially helpful in reducing the risk of prostate cancer:

• Whole grain cereals, seeds, and nuts have been associated with a lower risk for prostate cancer. Part of this protection may be due to their high fiber content. Fiber binds to sex steroids and is excreted, carrying the hormones with it. Whole grains also contain selenium, a trace mineral that may have some protective properties.
• Many studies have reported a significantly lower risk for prostate cancer with high intake of cooked tomatoes, which are high in a beneficial plant chemical called lycopene. (However, other studies have not reported such protection.)
• Soy may also be protective, which may partially explain the low rate of prostate cancer observed in Japanese men and vegetarians (who typically use soy as a protein replacement). Theoretically soy, which is a rich source of an estrogen-like plant compound, may inhibit hormones that promote prostate cancer. Laboratory studies are mixed on such effects, however.
• Cruciferous vegetables (cauliflower and broccoli) may have cancer-fighting chemicals.
• Boron-rich foods (nuts, red grapes, avocados, and dried fruits) may also be protective.
• Green tea. Scientists have speculated that the antioxidants contained in green tea may help to inhibit prostate cancer growth. Investigators are researching the effects of both green tea and green tea extract supplements, but results to date have been inconclusive.

Dairy Products, Calcium, and Vitamin D. Studies have reported an association between consuming large amounts of dairy products and a modestly increased risk for prostate cancer. (Moderate intake has not been associated with a higher risk.) There is some evidence that calcium (contained in dairy products) may increase the risk for prostate cancer by reducing levels of the most active form of vitamin D (1,25 dihydroxyvitamin D). Many studies indicate that vitamin D may help protect against prostate cancer. Men should make sure they are getting enough vitamin D through sunlight exposure, food, or vitamin supplements.

Getting enough calcium to keep bones from thinning throughout a person's life may be made more difficult if that person has lactose intolerance or another reason, such as a tendency toward kidney stones, for avoiding calcium-rich food sources. Calcium deficiency also affects the heart and circulatory system, as well as the secretion of essential hormones. There are many ways to supplement calcium, including a growing number of fortified foods.

Click the icon to see an image of the benefits of vitamin D.

Click the icon to see an image of the sources of vitamin D.

There is some evidence that certain vitamin and mineral supplements (such as vitamin E and selenium) can protect against prostate cancer, and also some evidence that excessive use of supplements may increase risk. In a 2007 National Institutes of Health study, men who took multivitamin supplements more than seven times a week increased their risks for developing advanced prostate cancer and for dying from the disease. The risks were highest for men who had a family history of prostate cancer and for those who took individual supplements of selenium, beta-carotene, or zinc. However, using multivitamin supplements occasionally or once a day does not appear to increase prostate cancer risk.

The National Cancer Institute is conducting a large-scale clinical trial of more than 35,000 men to investigate whether selenium, vitamin E, or a combination of these two dietary supplements can help to prevent prostate cancer. The Selenium and Vitamin E Cancer Prevention Trial (SELECT) is the largest prostate cancer prevention trial ever initiated.

Click the icon to see an image of the benefits of vitamin E.

Click the icon to see an image of the sources of vitamin E.

In general, a healthy diet with nutritious fruits and vegetables is the best way to meet your daily requirement of vitamins and minerals.

Alcohol consumption does not appear to be associated with increased prostate cancer risk. A recent study, however, suggested a linear trend between red wine consumption and reduced risk of prostate cancer. In a study of over 1,400 newly diagnosed middle-aged patients with prostate cancer, researchers found that each additional glass of red wine consumed per week reduced the relative risk of prostate cancer by 6%. Researchers theorize that the flavonoids contained in red wine may inhibit tumor cell growth. More research is needed to confirm these results.

Regular physical activity may help reduce the risk of prostate cancer and slow the progression of the disease. The beneficial effects of exercise may be particularly important for older men. A 2006 study found that men ages 65 and older who exercised vigorously for at least 3 hours weekly had a 70% lower risk of being diagnosed with advanced prostate cancer.

Finasteride (Proscar) is a drug used to shrink the prostate in men with benign prostatic hyperplasia (BPH). It blocks an enzyme that converts testosterone to dehydroepiandrosterone (DHEA), the form of the male hormone that stimulates the prostate. Researchers are investigating whether finasteride may help prevent prostate cancer. In the 2003 Prostate Cancer Prevention Trial (PCPT), more than 18,000 men were randomly assigned to receive either finasteride or placebo. The men took the pills daily for 7 years. Results, published in 2003 in the New England Journal of Medicine, indicated that men who took finasteride were 25% less likely to develop prostate cancer than men who took placebo. However, although the finasteride group had fewer prostate cancers overall, those that did develop were higher-grade and more aggressive. Men who took finasteride had more sexual problems, including episodes of erectile dysfunction, but were less likely to have urinary problems, such as incontinence. It is still unclear if finasteride is an appropriate preventive approach.

Frequent ejaculations from masturbation or sexual activity have been associated with a lower risk for prostate cancer. Some experts speculate that certain carcinogens may be concentrated in prostate fluid, so that frequent ejaculation helps eliminate them. Of note, risky sexual activity, such as with multiple partners, increases the risk for sexually transmitted disease, which in turn may increase the risk for prostate cancer.

There is some evidence that nonsteroidal anti-inflammatory drugs (NSAIDs) offer some protection against prostate cancer. NSAIDs suppress chemicals in the body called COX-2, a protein that may cause prostate cancer cells to spread. Standard NSAIDs include aspirin, ibuprofen (Advil), and naproxen (Aleve). However, NSAIDs taken on a long-term basis can increase the risk for heart and gastrointestinal problems.

Symptoms

Prostate cancer usually causes no symptoms in the early stages. As the malignancy spreads, it may constrict the urethra and cause urinary problems.

Urine flows from the kidney through the ureters into the urinary bladder where it is temporarily stored. As the bladder becomes distended with urine, nerve impulses from the bladder signal the brain that it is full, giving the individual the urge to void. By voluntarily relaxing the sphincter muscle around the urethra, the bladder can be emptied of urine. Urine then flows out through the urethra.

Later-stage urinary symptoms typically include:

• Weak urinary stream
• Inability to urinate
• Blood in the urine
• Interruption of urinary stream (stopping and starting)
• Frequent urination (especially at night)
• Pain or burning during urination

Significant pain in one or more bones may indicate the occurrence of metastases (spread of disease). This chronic pain occurs most often in the spine and sometimes flares in the pelvis, the lower back, the hips, or the bones of the upper legs. It may be accompanied by significant weight loss.

Conditions with Similar Symptoms

In up to half of men in their 40s, the prostate begins to enlarge through a process of cell multiplication called benign prostatic hyperplasia (BPH). The symptoms of BPH can mirror late-stage prostate cancer because the enlarging inner portion of the prostate puts pressure on the urethra, which can potentially cause urinary problems. About 80% of men eventually develop enlarged prostates, but only some experience significant symptoms. BPH is a normal condition and is not life-threatening. [See In-Depth Report #71: Benign prostatic hyperplasia.]

Benign prostatic hypertrophy (BPH) is a non-cancerous enlargement of the prostate gland, commonly found in men over the age of 50.

Relationship to Prostate Cancer. Because the prostate enlargement in BPH is affected by testosterone, many men are concerned that it may be related to prostate cancer. Fortunately, current evidence indicates that it has no effect one way or the other. The two conditions develop in different parts of the prostate. BPH occurs in the inner zone of the prostate, while cancer tends to develop in the outer area. A 10-year study found no higher risk for prostate cancer in men with BPH.

Click the icon to see an animation about benign prostatic hypertrophy.

Prostatitis is an inflammation of the prostate, often caused by bacterial infections. Symptoms include urgency, frequency, and pain in urination, sometimes accompanied by fever or blood in the urine.

Screening and Diagnosis

The prostate specific antigen (PSA) blood test is widely used for screening men for prostate cancer. However, there is great uncertainty over whether regular screening has major benefits for most men. The most recent guidelines from the U.S. Preventive Services Task Force report that there is no conclusive evidence that routine prostate screening saves lives. Indeed, it may lead to invasive testing, and to treatments for many men who, considering the slow growth of the cancer, might derive no benefits from them. It is a difficult subject, and men must discuss all aspects carefully with their doctor.

A 2006 study in the Archives of Internal Medicine also suggested that screening tests for prostate cancer may not reduce men’s risk of death. The small study of 1,000 men found no differences in survival between men who had prostate specific antigen tests or digital rectal exams, and men who were not screened. Doctors should inform men of the uncertainty of prostate cancer tests so that patients understand the relative risks and benefits of screening

Standard Screening Tests for Early Detection. Two standard tests are used for early detection of prostate cancer:

• Digital rectal examination (DRE). With the DRE, a doctor palpates the prostate in order to feel lumps or masses.
• PSA test. The PSA blood test measures the level of a protein called prostate-specific antigen. It is able to detect early prostate cancer, although it has limitations.

If the digital rectal examination indicates the possible presence of cancer, regardless of the PSA results, a doctor may also obtain a visual image of the prostate through an ultrasound procedure called transrectal ultrasonography (TRUS). Only a biopsy, however, in which a tiny sample of prostate tissue is surgically removed, can actually confirm a diagnosis of prostate cancer.

Candidates for Annual Screening. Until major studies report on the survival benefits of prostate screening, expert groups recommend the following:

• Men ages 50 - 70 should be offered annual screening. (Some experts believe that men whose PSA levels are under 1.0 and possibly under 2.0 may safely be screened only every 2 years thereafter.)
• Men with a family history of prostate cancer and all African-American men should consider annual screening at about age 45.
• Experts agree that PSA testing is inappropriate for men over age 70. PSA testing in this age group can cause more harm than good by leading to overly aggressive treatment. Despite this fact, many elderly men continue to receive unnecessary PSA tests.

The best age to start annual screening is under debate. Some experts advocate performing a first PSA test in all men aged 40 and then monitoring anyone whose PSA levels are over 0.60 ng/mL. They argue that such men are at high risk for developing prostate cancer within 25 years. A study presented at the 2007 meeting of the American Urological Association suggested that even a small increase in PSA in men age 44 - 50 may predict whether advanced prostate cancer will develop later in life.

Researchers are working on developing more accurate tests that, hopefully, will one day replace the PSA test. A promising test in development measures a protein called early prostate cancer antigen-2 (EPCA-2). A 2007 study suggested that the EPCA-2 test is highly accurate. It can distinguish between benign prostatic hyperplasia (BPH) and prostate cancer and can evaluate whether or not a man has prostate cancer, regardless of what his PSA levels indicate. Researchers hope that this test may eventually provide better diagnoses of prostate cancer, and help prevent men from receiving unnecessary biopsies.

About 90% of all prostate cancers arise in the outer part of the prostate where they may be detected by a digital rectal exam (DRE), which is the simplest and most widely-performed screening procedure. The doctor inserts a gloved and lubricated finger into the patient's rectum and feels the prostate for bumps or other abnormalities. The exam is quick and painless but some men find it embarrassing. It is not very accurate in detecting early cancers, but studies indicate that regular DREs still save lives.

Prostate Cancer is the most common cancer in men in the United States. Prostate cancer forms in the prostate gland, and can sometimes be felt on digital rectal examination. This is one of the purposes of the digital rectal exam.

Prostate specific antigen (PSA) is a protein produced in the prostate gland that keeps semen in liquid form. Prostate cancer cells appear to produce this protein in elevated quantities. Measuring PSA levels increases the chance for detecting the presence of cancer when it is microscopic. There are many unresolved questions surrounding PSA testing. The test is not accurate enough to either completely rule out or confirm the presence of cancer. Relying too much on the test may lead to unnecessary biopsies. Not relying on it enough may miss cancers. It is still unclear if PSA testing is actually saving lives.

Click the icon to see an image of a PSA blood test.

Indications for Biopsy. A biopsy is usually performed to confirm or rule out cancer after screening tests that report:

• PSA level of 4.0 ng/mL or higher. Some evidence indicates that men with an initial test showing PSA levels above 4.0 should take a second PSA test several weeks afterward before having a biopsy, since many non-malignant factors can increase PSA levels. (Some experts urge biopsies even if PSA levels fall below 4.0 mg, particularly in men under 60, since lower levels do not necessarily rule out cancer.)
• Abnormal digital rectal examination (DRE).

Men with abnormal results from both tests have a 60% chance of prostate cancer. The chances for cancer if only one test is abnormal are considerably lower. To further complicate matters, biopsies themselves may miss very small cancers detected by PSA levels alone.

Factors Affecting PSA Levels. A number of factors and noncancerous conditions can influence PSA levels:

• Ethnicity. Normal levels in Caucasian males may be different from those for African-American or Asian men. For example, using PSA screening, one study suggested that 15% of Caucasians and 37% of African-Americans are overdiagnosed with prostate cancer based upon PSA results. Some experts believe that there should be different scales for determining risk among these groups, but there is still not enough information to determine a specific range for various ethnic groups.
• Age. PSA levels tend to rise naturally with age, so an elevated level in a man who is 70 may be less serious than the same level in a younger man. Some experts believe that men older than 65 who have low PSA levels are at such low risk for prostate cancer that they may be able to forgo further testing.
• Benign Prostatic Hyperplasia (BPH) and Its Treatments. Between 25 - 56% of patients with BPH have elevated PSA levels. Certain treatments for this condition can also elevate PSA.
• Prostatitis. About half of men with elevated PSA levels but no signs of cancer on biopsy have signs of prostatitis as indicated by urine and prostate secretion tests. (Prostatitis simply means inflammation in the prostate. Inflammation is usually due to bacterial infection, but it can also be caused by nonbacterial factors.) In one study, screening for prostatitis increased the accuracy of the PSA test significantly and reduced the number of unnecessary biopsies.
• Other Noncancerous Conditions. Other noncancerous conditions that can increase PSA levels include surgical procedures or drug treatments for BPH, acute urinary retention, digital rectal examinations, and prostate biopsies themselves.
• Ejaculation. Ejaculation within 48 hours before testing can raise PSA levels.

Even with its limitation, the PSA test has increased the number of detectable early-stage and therefore treatable cancers. Because of the slow-growing nature of prostate cancer, however, it is not known whether all of these very early cancers will result in significant or life-threatening disease. It is possible that PSA screening could result in the detection of some possible cancers that would never have bothered the patient and would never have posed a threat to his life.

To improve the accuracy of the PSA tests, particularly when PSA levels have risen to an intermediate range of between 4 - 10 ng/mL, researchers are developing methods for measuring other factors. To date, no test has emerged as clearly superior to the PSA test.

Free PSA Test. A small amount of prostate specific antigen leaks out of the prostate into the bloodstream. There, PSA can circulate without binding to other proteins and is referred to as free PSA. It can also form chemical combinations with other proteins. If cancer is present, PSA is more likely to be bound, and so there is less free PSA in circulation. The free PSA blood test, then, is a ratio of free PSA to the total PSA (free PSA plus chemically bound PSA).

The following results are used to determine if an elevated PSA level could mean cancer:

• A free-to-total PSA ratio of 20% or lower, plus total PSA levels of 4 - 10 ng/mL, are suggestive of prostate cancer. (Some experts use 25% as a cut-off, but studies suggest that using this cut-off would miss cancers in many African-American and older men.)
• A free-to-total PSA level of more than 20% plus normal or even moderately elevated total PSA tend to indicate the presence of other, benign conditions, such as benign prostatic hyperplasia (but it still does not rule out cancer).

Some studies have reported that adding a test for free PSA may improve prostate cancer detection by roughly 40% and may also reduce the need for unnecessary biopsies. In addition, any cancers that the test misses would not develop into significant disease for many years, providing ample opportunity to identify them before they became serious. Not all studies support its advantages, however, compared to measuring total PSA alone, and to date there is no consensus among doctors for how it can be used.

Complexed PSA Test. Complexed PSA (cPSA) is a form of circulating PSA that is bound to a molecule called alpha1-antichymotrypsin. It represents about 90% of the total PSA in men and is significantly higher in men with prostate cancer than in those with BPH. To date, studies have reported conflicting results on its benefits for diagnosing prostate cancer.

Transition Zone PSA Test. Some tests have been developed to measure the density of the PSA in the transition zone of the prostate gland. (The transition zone is the central area of the prostate that wraps around the urethra.) A major comparison study in 2002 reported more accurate results than with complexed PSA.

An ultrasound procedure called transrectal ultrasonography (TRUS) provides a visual image of the prostate and is used if the DRE indicates the presence of cancer. Ultrasound is not effective as a diagnostic tool by itself because it cannot differentiate very well between benign inflammations and cancer, but the procedure may help to confirm an uncertain preliminary diagnosis and is useful as a guide for needle biopsies. Ultrasound enhancements, such as Doppler imaging or computer modeling techniques called artificial neural networks (ANN), may increase the accuracy of TRUS.

Initial Biopsies. If preliminary tests raise the suspicion of cancer, doctors will perform a biopsy. Biopsy is used to diagnose prostate cancer, and is a very accurate method for predicting the severity of an existing cancer. However, biopsies can still miss cancers if they are very small.

• Core Biopsy. The standard method is called a core biopsy, which uses a spring-loaded biopsy device inserted into the rectum. The device propels a needle into the prostate, obtaining a core of tissue, which is examined by pathologists.
• Fine Needle Aspiration. A more recent procedure, called fine needle aspiration, is less painful and may be as accurate as a core biopsy if the sample obtained is sufficient for analysis and if it is analyzed by a skilled pathologist.

More than half of the men who have a biopsy experience discomfort and anxiety, with men under 60 reporting higher levels of discomfort than older men. Taking a sedative 1 - 2 hours before the procedure can help reduce distress. Complications of biopsy are low, but urinary tract infection, fever, or bleeding occurs in 0.1 - 4% of men.

Repeat Biopsies. Because a biopsy can miss very small cancer cells, sometimes three or even more biopsies are recommended if cancer is still suspected after negative results, such as when:

• PSA levels are high. Two or more biopsies may be taken if a man has very high PSA levels and still has normal results on a biopsy. Even men with mildly elevated PSA (between 4 - 10 ng/mL) who test negative may be given a repeat biopsy. Cancer will be detected in about 10% of this group. Whether a third biopsy is useful in these men if they still test negative after a second biopsy is uncertain.
• DRE results are abnormal.
• Ultrasound results are abnormal.
• The initial biopsy yields microscopic findings that are suspicious.
• The initial biopsy detects precancerous cells known as high-grade prostatic intraepithelial neoplasia (PIN). No treatment is necessary with this finding, but these patients should be rechecked every 3 - 6 months for the next 2 years, and then annually.

Doctors may also perform a lymph node biopsy to see if the cancer has spread.

Tests to Determine Severity of Cancer

Once cancer is diagnosed, PSA levels may help to determine its extent. If PSA levels are less than 20 ng/mL, it is possible that the cancer has not spread to distant sites. PSA levels over 40 ng/mL are a strong indicator that cancer has metastasized (spread throughout the body). PSA levels are also monitored after treatments begin. Changes in the level can show if a treatment is working or if the cancer has come back.

Doctors also monitor how quickly PSA levels rise over time. This rate is called PSA velocity (PSAV). The PSAV is very helpful in determining when treatment should begin and which treatment should be used. A high rate of PSAV is considered to be 2 ng/mL a year. Recent research suggests that men with early-stage prostate cancer who have a slow PSAV are more likely to live longer than men with rapidly rising PSA levels.

A number of biological factors are being used or investigated as markers for cancer or its severity:

Chromosomal Sets. The number of chromosomal sets in the nucleus of the tumor's DNA, known as its ploidy, is an important marker for patients in late stages of prostate cancer. Tumors with the normal two sets of chromosomes, called diploid tumors, usually have a more favorable outcome than tumors that have four sets of chromosomes (tetraploid tumors) or have an abnormal number of individual chromosomes (aneuploid tumors).

Blood Vessel Density. The density of blood vessels in the tumor is an important indicator of outcome. The greater the density, the more likely the tumor is to be aggressive.

Serum Acid Phosphatase. High levels of this enzyme indicate a more aggressive disease and the need for intensive treatments.

Testosterone Levels. Higher total testosterone levels may increase the risk for metastasis. A 2000 study found an association with low free testosterone and more extensive prostate cancer, suggesting free testosterone could be a marker for aggressive disease. (Free testosterone, as with free PSA, is not chemically bound.)

Genetic Markers. Researchers have identified a genetic marker (EZH2), which may prove to be an important marker for aggressive prostate cancer. It may, in fact, prove to be a better predictor of outcome than the tumor grade, stage, or surgical margins. Other genes being studied are those that regulate tumor growth (p53, p27, bcl-2).

Other Markers. Other markers being investigated for predicting cancer progression include prostate-specific membrane antigen, prostatic acid phosphatase, and growth factors.

The ProstaScint is a scanning technique that uses tiny amounts of radioactive material with a monoclonal antibody that can attach specifically to prostate cancer cells. A special camera then can detect tumor cells that cannot be detected with other diagnostic tools. It may help doctors make better treatment decisions. The role of this test in the routine management of prostate cancer is still being defined.

If the biopsy indicates cancer, the doctor will order other tests to determine whether or how far the cancer has spread.

Bone Scans and X-Rays. Bone scans and x-rays may reveal whether the cancer has invaded the bones. To perform a bone scan, doctors inject low doses of a radioactive substance into the patient's vein, which accumulates in bones that have been damaged by cancer. A scanner then reveals how much of the radioactive material has accumulated. Arthritis and infections may also produce positive scans. Patients with PSA levels below 20 ng/mL are unlikely to have scans that show cancer in the bone.

A radiotracer is injected into a peripheral vein. As the radiotracer decays, gamma radiation is emitted and is detected by a Gamma camera. When the tracer has collected in the target organ the area is scanned. Radionuclide scans can detect abnormalities such as fractures, bone infections, arthritis, rickets, and tumors that have spread, among other diseases.

Computed Tomography and Magnetic Resonance Imaging. Computed tomography (CT) or magnetic resonance imaging (MRI) scans can further pinpoint the location of cancer that has spread beyond the prostate. Advanced MRI techniques are showing promise for staging and planning treatments.

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

Click the icon to see an image of a MRI.

Bone Metastasis Markers. Researchers are investigating chemical markers, such as amino-terminal propeptide of type I procollagen (PINP), as early indicators of bone metastasis.

Treatment

Because BPH rarely causes serious complications, men usually have a choice between treating it or opting for watchful waiting:

• Watchful Waiting. Watchful waiting (also called active surveillance) involves lifestyle changes and an annual examination. Even when choosing watchful waiting, an initial examination is critical to rule out other disorders.
• Treatment Options. The primary goals of treatment for BPH are to improve urinary flow and to reduce symptoms. Many options are available. They include drug therapies, minimally invasive procedures, and major surgery.

The choice between watchful waiting and treatment usually depends on a number of factors, such as urine flow rates, prostate size, and PSA levels. Men with BPH who develop symptoms at around age 50 are more likely to need treatment within their lifetimes than older men. Unfortunately, there is no current way to determine who specifically might be at risk for serious problems and need early treatment.

The development of the International Prostate Symptoms Score (IPSS) has made the evaluation of symptoms somewhat easier. This scoring service serves as a benchmark for determining severity. The decision to treat or not to treat is typically based on the guidelines described below, but the ultimate choice is often guided primarily by a man's perception of his own symptoms.

Mild, or No, Symptoms. Men with mild, or no, symptoms (IPSS scores of 7 or below) usually choose watchful waiting even if their prostates are enlarged. BPH eventually progresses to the point of needing treatment in about 15% of men with mild symptoms who wait.

Moderate Symptoms. The choice is most difficult for men with moderate symptoms (scores between 8 - 19) and may simply depend on a man's ability to tolerate them. Some studies have reported that up to 40% of men with moderate symptoms eventually seek treatment, and a quarter require surgery. In a small percentage of patients, symptoms improve.

Severe Symptoms. Men with severe symptoms (scores over 20) nearly always choose treatment, although if their prostate glands are small or normal-sized, symptoms may improve.

If a man opts for treatment, there are several choices. Most experts recommend a staged approach as follows:

• Mild Symptoms. Medications are the best choice for men with mild symptoms who decide to have their condition treated. There are two standard choices: alpha-blockers and anti-androgens, nearly always finasteride (Proscar). Specific conditions determine the choice, although most men take an alpha-blocker. Men with mild symptoms who choose surgery only experience minor improvement afterward but face the same risks as patients with more severe symptoms.
• Moderate-to-Severe Symptoms. Men with moderate-to-severe symptoms often respond to the same medications as men with mild symptoms. (Combinations of alpha-blockers and finasteride are under investigation.) Recent developments in drug therapy have reduced the number of surgical procedures needed and delayed their use. However, a quarter of men with moderate symptoms, and even more men with severe symptoms, eventually need surgery. If a man chooses surgery, there are many choices. Transurethral resection of the prostate (TURP) is the standard procedure, but less invasive procedures, particularly those using heat or lasers to destroy prostate tissue, are gaining prominence.

Click the icon to see an illustrated series detailing transurethral resection of the prostate surgery.

The most common reason for choosing surgery is obstruction of the bladder outlet, which causes urinary retention. Surgery is also typically a reasonable option when BPH is clearly related to one or more of the following conditions:

• Recurrent urinary tract infection.
• Hematuria (blood in the urine). Studies have suggested that when hematuria is left untreated, two-thirds of patients continue to bleed and one third require surgery. The drug finasteride may help some men with this condition and should probably be tried before surgery.
• Bladder stones.
• Kidney problems.
• Some experts believe that surgery might benefit patients for whom an early diagnosis of prostate cancer is important. Unsuspected prostate cancer is detected during surgery in about 15% of cases.

The greatest improvements resulting from surgery are usually increased urinary flow and reduced urine retention. In one study, men who chose surgery reported more worry and depression before the procedure, but afterward they had less depression and anxiety than those who had chosen medication. Often, however, the benefits of surgery are not permanent.

Treatment Options by Staging and Grading

Stages indicate the extent of the cancer:

• Stage I and stage II cancer are considered early stage. The cancer is localized and has not spread outside the prostate gland.
• Stage III, locally advanced cancer, means that the cancer has spread into the seminal vesicles (glands at the base of the bladder, which are connected to the prostate gland and help produce semen).
• Stage IV is advanced cancer. The cancer has spread to the lymph nodes and other tissues or organs.

Experts have devised treatments based on classification systems, including staging and tumor grade. However, there are no clear-cut answers on the best treatments for particular stages. In addition to staging, other factors must be considered. These factors include the patient’s age, overall health status, and personal preferences concerning side effects and quality of life. In addition to standard treatments, patients may also wish to consider enrolling in clinical trials of investigational treatments.

The U.S. National Cancer Institute recommends the following treatment options by cancer stage:

Tumors: T1a, N0, M0, G1, Stage A

• Active surveillance
• Radical prostatectomy, usually with pelvic lymphadenectomy, with or without radiation therapy after surgery
• External beam radiation therapy
• Implant radiation therapy (brachytherapy)
• Clinical trial options include high-intensity focused ultrasound

Click the icon to see an illustrated series detailing prostatectomy surgery.

Tumors: T1a - c, N0, M0, any G, Stage A2, B1, or B2

• Radical prostatectomy, usually with pelvic lymphadenectomy, with or without radiation therapy after surgery
• Active surveillance
• External beam radiation therapy with or without hormone therapy
• Implant radiation therapy (brachytherapy)
• Clinical trial options include radiation therapy with or without hormone therapy; ultrasound-guided cryosurgery; hormone therapy followed by radical prostatectomy

Tumors: T3, N0, M0, any G, Stage C

• External beam radiation with or without androgen deprivation therapy (hormone therapy)
• Androgen deprivation therapy
• Radical prostatectomy, usually with pelvic lymphadenectomy, with or without radiation therapy following surgery
• Radiation therapy, androgen deprivation therapy or transurethral resection of the prostate (TURP) to relieve symptoms
• Clinical trial options include ultrasound-guided cryosurgery

Click the icon to see an illustrated series detailing transurethral resection of the prostate.

Tumors: Any T, any N, any M, any G, Stage D1 - D2

• Androgen deprivation therapy
• External beam radiation therapy with or without androgen deprivation therapy
• Radiation therapy or transurethral resection of the prostate (TURP) to relieve symptoms
• Active surveillance
• Clinical trial options include radical prostatectomy with surgery to remove both testicles (orchiectomy)

Treatment options are dependent on various factors, including prior treatment, site of recurrence, coexistent illnesses, and individual patient considerations.

• Patients whose cancer recurs locally after prostatectomy: Radiation therapy, androgen deprivation therapy.
• Patients whose cancer recurs locally after radiation therapy: Androgen deprivation therapy, prostatectomy (very select patients).
• Patients whose recurrent cancer has spread: See treatment options for stage IV.

Treatment for Localized Prostate Cancer

Choosing the best treatment for localized prostate cancer (T1 or T2) is generally based on the patient's age, the stage and grade of the cancer, overall health status, and the patient's personal preferences for the risks and benefits of each therapy.

Patients have three main options:

• Active surveillance, also called watchful waiting, involves monitoring the tumor for cancer progression to determine if and when treatment should be started.
• Surgery (radical prostatectomy) removes the prostate gland. The vessels that carry semen and surrounding tissue may also be removed. Studies indicate that compared to watchful waiting, radical prostatectomy may lower the risk of cancer recurrence and death, particularly for younger men with aggressive tumors.
• Radiation therapy targets the tumor either externally (external beam radiation) or internally (implanted “seeds”).

In 2007, the American Urological Association (AUA) released guidelines for the treatment of localized prostate cancer. The guidelines recommend that patients should be classified as low, intermediate, or high risk. Doctors determine the risk category by using criteria such as PSA tests, tumor aggressiveness, and the clinical stage of the tumor.

Among the AUA’s treatment recommendations:

• Compared with active surveillance, radical prostatectomy may lower the risk of cancer recurrence and death.
• For men at intermediate and high risk, adding androgen deprivation therapy to external beam radiation may improve survival. A higher dose of external beam radiation also improves the odds for survival.
• Initial (first-line) androgen deprivation therapy is seldom recommended for localized prostate cancer except for the relief of symptoms in patients with poor prognoses. Androgen deprivation therapy can increase the risks for diabetes and heart disease.
• Patients with localized prostate cancer should have the opportunity to enroll in clinical trials investigating new types of therapy.

Conflicting Data on Survival Rates. To date, neither treatment nor active surveillance has emerged with a definitive survival advantage. Several studies from 2005 and 2006 suggested that treatment provides a survival advantage over watchful waiting for some men with early-stage prostate cancer. A 2005 New England Journal of Medicine study reported that men who had a radical prostatectomy before age 65 had a reduced risk of death from prostate cancer, death from other causes, localized cancer progression, and metastases than men who chose watchful waiting.

Similarly, research presented at the 2006 Prostate Cancer Symposium found in a study of nearly 50,000 men with early-stage prostate cancer that men who had radiation or surgical treatment had a 30% lower risk of death than men who were randomly assigned to watchful waiting. However, a 2005 Journal of the American Medical Association study advised against aggressive treatment for localized low-grade prostate cancer. The study found that men with low-grade prostate cancer had a small risk of cancer progression even after 20 years of watchful waiting or hormonal drug therapy

Imperfection of Classification System. The classification systems are not perfect. Even if tumors are rated in low stages and grades and are treated accordingly, undetected cancer cells may escape and spread beyond the prostate. Other factors, such as the man's age and medical condition, must be included in determining whether aggressive treatments or conservative measures are appropriate.

Specialty Bias. Patients should be aware that doctors may be biased to prefer a specific treatment depending on their specialty. For example, in one study the following treatments were favored for patients who were generally appropriate candidates for either surgery, radiation, or watchful waiting:

• 93% of urologists recommended radical prostatectomy.
• 72% of radiation oncologists recommended radiation. (And 82% thought that radical prostatectomy was overused.)
• Virtually none of the doctors recommended watchful waiting for higher-risk disease. When in doubt, patients should always seek a second opinion to help them make this important choice.

Quality of Life. Surgery and radiation both have potentially distressing side effects, including the possibility of impotence, incontinence, or both. A man must weigh his own emotional responses to the possibility of these side effects versus the possible stress of watchful waiting.

In general, differences in quality of life after surgery or radiation treatment have to do with the specific effects of each type of treatment:

• Radiotherapy generally causes more bowel problems than surgery, 30 - 35% versus 6 - 7%, according to a 2001 study. In a 2003 review, the risk for impotence from radiotherapy varied from 25% with brachytherapy to 45% with external beam radiotherapy.
• Prostatectomy causes more urinary incontinence (39 - 49% versus 6 - 7% for radiotherapy patients) than radiotherapy. Risks for impotence range from 66% after nerve-sparing prostatectomy to 87% after cryotherapy. In spite of these adverse effects, a 2002 study reported no meaningful differences in well-being or quality of life during a 4-year period for men who chose surgery versus those who chose watchful waiting.
• Active surveillance could lead to cancer growth that eventually obstructs the urinary tract (which can happen with the treatments as well). It may also impose an emotional burden on men who live with the possibility of progressive cancer and its difficult treatments. Some who decide to wait become what some doctors refer to as the "walking worried," men who are constantly concerned with their PSA levels. Because aggressive treatment reduces such anxiety, some studies reported that years after surgery, about 75% of men said they would chose it again, in spite of the significant side effects.

Watchful waiting involves lifestyle change and careful monitoring for cancer progression. Over the last several years, watchful waiting has evolved into a strategy called “active surveillance” or “delayed surgical intervention.” With this approach, patients have a digital rectal exam and PSA blood test every 6 - 12 months. If test results indicate cancer progression, then treatment options (surgery, radiation, drugs) are considered. Patients should exercise and eat healthy foods. Patients should report symptoms such as weight loss, pain, urinary problems, fatigue, or impotence to their doctors.

Candidates. Active surveillance may be most appropriate for the following patients:

• Men in their late 70s and older. More aggressive therapies (surgery and radiation) are usually recommended for men in their 50s and younger. The choice for men in their 60s and early 70s is more problematic. The general recommendation is that aggressive therapy is suitable for those who have a life expectancy of more than 10 years and who have localized but mid- to high-grade tumors. The tumor grade may be the best guide for determining the risks in choosing watchful waiting.
• Elderly men with early-stage (T0 - T2) low-grade tumors.
• Men with low-to-moderate (3 - 13 ng/mL) PSA levels.

Some experts think that because prostate cancer grows so slowly, it is likely that older men will die from causes unrelated to the cancer. There is therefore little potential benefit from surgery or radiation, with both posing a risk for impotence and incontinence. However, some recent surveys suggest that more men are choosing treatment (especially surgery) over active surveillance. The choice is a difficult one. It is important that patients find a doctor who can provide them with all the necessary information so that they can make an informed decision.

In men whose cancer is confined to the prostate, surgical resection (radical prostatectomy) offers the potential for cure. Cure rates from initial surgery in men with localized cancer are about 70%, depending on tumor stage, tumor grade, and PSA levels. Research suggests that surgery provides long-term cancer control. Most patients can consider themselves disease-free if their PSA levels remain undetectable 10 years after surgery.

Candidates. Radical prostatectomy is a consideration for men who meet all of the following criteria:

• In good health and with a life expectancy of 10 years or more. As average life expectancy in men has increased, more older men are becoming candidates for surgery. Complication rates are higher the older a man is, however.
• The cancer has not spread beyond the prostate gland.
• The cancer is potentially life threatening. (In general, a life-threatening tumor is indicated by volumes more than 0.2 cc and Gleason grade scores greater than 5.)

The procedure is more likely to cause incontinence (up to 50%) than radiation treatment but has fewer bowel complications. Impotence rates are about the same. Surgery for prostate cancer may be particularly difficult in men who have had transurethral resection of the prostate (TURP).

Radiation therapy (or radiotherapy) is administered as external beam radiation or as brachytherapy (radiation implants). It may be used as the sole primary treatment for localized prostate cancer; 5-year survival rates are similar to those of surgery.

Candidates. Radiation is considered for men with one or more of the following characteristics:

• Being older and, particularly, having other medical problems.
• Cancer has extended beyond the prostate capsule but has not spread to the lymph nodes or further.
• Being a good surgical candidate, but having decided against an operation.

The risk for incontinence (less than 10%) is much lower than with surgery, although bowel problems occur in about a third of patients. Impotence rates are about the same.

Androgen Deprivation Therapy With Radiation. Hormonal (“androgen deprivation”) drugs combined with radiation therapy may improve survival rates in moderate- or high-risk groups. Patients may need to take these drugs long-term to improve outcomes. Hormonal drugs before radiation (neoadjuvant therapy) may be helpful in shrinking enlarged glands so that brachytherapy (radiation implants) can be used. Hormone therapy can also be given at the same time or following radiation.

An important study published in 2004 in the Journal of the American Medical Association (JAMA) found that for men with localized prostate cancer, a 6-month course of androgen deprivation therapy combined with radiation treatments produced greater survival rates than radiation treatment alone. Standard medical practice has generally indicated that hormone therapy should be given for 3 years; the JAMA study suggests that a shorter regimen may be equally beneficial for some patients and may help reduce the side effects that typically accompany androgen-suppressing drugs.

A 2005 JAMA study suggested that PSA velocity (PSAV) may help doctors decide which patients should receive androgen deprivation drugs along with radiation therapy. PSAV lets doctors calculate how quickly a patient’s PSA level has risen. Researchers found that men who had at least a 2.0 ng/mL increase in PSA levels during the year before their cancer diagnosis had a high risk of dying after external beam radiation therapy, even though they had low-grade prostate cancer. The study suggests that men with this particular PSAV history should consider combining radiation therapy with androgen deprivation drugs.

Surgery

Radical prostatectomy is the surgical removal of the entire prostate gland along with the seminal vesicles (the vessels that carry semen) and surrounding tissue. The incision can be made in one of the following regions:

• Retropubicly (through the abdomen and under the pubic bone, exposing the entire surface of the prostate).
• Through the perineum (the skin between the scrotum and the anus).

The gland and other structures are then removed. The operation lasts 2 - 4 hours. Advanced surgical techniques, such as minilaparotomy and laparoscopy, are being developed for radical prostatectomy. These techniques use smaller incisions, are less invasive, and may cause fewer complications.

Click the icon to see an illustrated series detailing prostatectomy surgery.

Nerve-Sparing Techniques. Surgical procedures have been refined over the years, and many operations for localized low-grade prostate cancer now spare the nerves that control erection.

• A bilateral nerve-sparing procedure saves the nerves on both sides of the sex organs.
• A unilateral procedure saves nerves on only one side.

Nerve-sparing techniques can improve quality of life. The ability for sexual intercourse recovers in about a third of patients at 3 years and nearly 60% at 5 years after surgery. (Rates vary depending on certain factors, such as the patient's age -- the younger the better.) In cases where the tumor is bulky and undifferentiated, nerve-sparing techniques may not be appropriate.

Convalescence. Patients remain hospitalized for up to 2 weeks. A temporary catheter used to pass urine is kept in place when the patient is sent home and usually removed about 3 weeks after the operation. The convalescent period at home is about a month. In general, younger patients with early-stage cancers recover fastest and experience the fewest side effects.

Complication rates vary after radical prostatectomy and usually depend on the age of the patient and the experience of the surgeon and medical center. They can range from 4% in men in their 40s to 14% in men over age 70. Complication rates are 10 times higher in patients who have prostatectomy because of cancer recurrence after radiation treatment.

Complications include the usual risks of any surgery, such as blood clots, heart problems, infection, and bleeding. Complications specific to radical prostatectomy, (incontinence, impotence, and contracture of the bladder neck), are discussed below. The mortality rate is very low, about 0.4%.

Quality of life usually improves shortly after surgery, and recovery from certain complications, such as incontinence and sexual function, can continue to occur even over years.

Urinary Incontinence. Urinary incontinence is a common complication and a more distressing side effect of surgery for most men than sexual dysfunction. When the urinary catheter is first removed following surgery, nearly all patients lack control of urinary function and will leak urine for at least a few days and sometimes for months. Major medical centers report that continence returns within about 18 months for nearly all men younger than age 70 and in the great majority of men older than 70. The average time for return of continence in one center was just 1.5 months.

Click the icon to see an image of catheterization.

A number of approaches may help prevent or treat incontinence:

• Nerve-sparing techniques can help prevent incontinence, although even in experienced centers, 8% of patients will have some postoperative incontinence, and this rate is much higher (up to 50%) in many community medical centers.
• A procedure called endopelvic anterior urethral stitch (EAUS) used with prostatectomy appears to reduce urinary incontinence. In one small study, 75% of selected patients recovered continence in a month. The procedure requires a simple stitch at the front of the urethra.
• Kegel exercises, contracting and relaxing the muscles used to shut off the urinary stream, strengthen the muscles on the pelvic floor and are reported to be very beneficial for many men.

If incontinence persists beyond a year, patients may require drug therapy or surgery. Collagen injections into the urethra, bladder neck suspension surgery, or a urinary sphincter implant may be helpful for men who have chronic incontinence. [See In-Depth Report #50: Urinary incontinence.]

Impotence. Studies suggest that about 40% of men have problems with erection after the procedure. In one study, however, more than 70% said they would have the procedure again. Nerve-sparing procedures are proving to be helpful in reducing impotence as well as incontinence.

Sildenafil (Viagra) may help restore potency on average in about a third of patients, but some men may do better than others. In one study, for example, 80% of younger men who were potent before surgery and had bilateral nerve sparing procedures responded to the drug. (Only 40% responded with only unilateral procedure.) Sildenafil is unlikely to be effective for men who had unilateral or no nerve sparing procedures. In those who respond, sildenafil may provide a benefit for years. Sildenafil may take 9 months or longer to become effective. Men who take it may benefit from alprostadil injections started right after surgery to preserve elasticity and help prevent scarring.

Early treatments with alprostadil injections may helpful in restoring erectile function in any case. This treatment maintains blood flow in the penis, and some research suggests that impotence after prostate surgery may be due in part to injury to these blood vessels. In one study, men administered injections every other night for 6 months. They then started taking sildenafil 3 months after surgery. At 6 months, 82% of these men achieved penetration compared to only 52% of men who took Viagra only. The vacuum pump may serve a similar purpose as the injections. [See In-Depth Report #15: Erectile dysfunction.]

Even when erectile function is preserved, men may experience other sexual problems:

• Erections may not be as rigid as before the operation.
• Orgasm and sexual sensation may be altered.
• Patients who retain potency may suffer from retrograde ejaculation, also known as dry ejaculation. During ejaculation, semen travels backward into the bladder, causing infertility.

Fecal Incontinence. Radical prostatectomy can also cause fecal incontinence. The risk may actually be higher in men undergoing nerve-sparing procedures.

Contracture of the Bladder Neck. Another common postsurgical complication is contracture of the bladder neck at the point where it has been stitched to the remainder of the urethra. Contracture usually occurs within the first 3 months after the operation, causing a sharp decrease in urinary stream. The condition can be treated by dilation or surgery on the bladder neck, and rarely recurs.

Pelvic lymphadenectomy is the surgical removal of the pelvic lymph nodes. It is usually performed at the same time as prostatectomy. If the surgeon suspects that cancer has spread beyond the prostate, the surgeon will perform the lymphadenectomy as part of the operation. Some surgeons do this procedure as a matter of course when performing prostatectomy, since it has few complications and adds information on the state of the disease. The lymph nodes are removed through an incision in the lower part of the abdomen, using conventional surgery or laparoscopy, a less invasive variation. The nodes are immediately examined. If they show signs of cancer, metastasis has occurred. In such cases, the operation is usually stopped and the patient is offered radiation or hormone treatments.

Click the icon to see an image of the pelvic lymph nodes.

Transurethral resection of the prostate (TURP) involves removing a section of the prostate with a surgical instrument (resectoscope) that is inserted through the urethra. TURP may be used to control urinary symptoms in men who are not good candidates for curative therapy due to advanced age, health status, or other reasons. TURP is also used as a treatment for benign prostatic hyperplasia (BPH).

Cryosurgery is an alternative to standard prostatectomy. The goal of cryosurgery is destruction of the entire prostate gland and possibly surrounding tissue. Steel probes are inserted through the skin between the anus and the rectum and into the prostate. Liquid nitrogen is pumped through the probes to freeze all prostate cells, both healthy and cancerous. For success, cryosurgery requires a uniformly frozen area. The dead cells are absorbed and eliminated by the body. Patients can leave the hospital in 2 - 3 days.

Candidates. Cryosurgery may be considered for patients with:

• Early stage local cancer
• Cancer that has recurred after radiation treatments
• Large primary tumors that the surgeon wishes to reduce
• Possibly tumors that have spread beyond the prostate if they have not yet reached the lymph nodes

Strong predictors of treatment failure include:

• A history of both hormonal and radiation treatments
• Tumor grades 8 and above
• PSA levels of more than 10 ng/mL

Complications. Complications are similar to those of standard prostatectomy, but incontinence rates are much lower. Impotence rates, however, are much higher. Nevertheless, 96% of patients report that they are satisfied with the results. Incontinence and other side effects may be higher in patients who have had previous radiation treatments. Other significant complications include scarring and narrowing of the urethra, and fistulas (abnormal passages from internal organs to the skin or between two internal organs).

Radiation Treatments

The two major radiation treatments are:

• External beam radiation
• Brachytherapy (internal radiation)

Both treatments have generally equal success rates. Research presented at the 2006 Prostate Cancer Symposium indicated that the two therapies work equally well for treating localized prostate cancer. In some cases, both techniques may be used in high-risk patients.

In external beam radiation therapy, a doctor focuses a beam of radiation directly on the tumor for 35 3-minute treatments given 5 times a week over 7 weeks. 3-D conformal techniques use computers and a three-dimensional image of the prostate to target the tumor precisely, using high-dose radiation beams. It poses a lower risk for inflammation. Men who have had transurethral resection of the prostate (TURP) or have a history of lower urinary tract symptoms may be particularly good candidates for 3D conformal techniques.

According to the 2007 American Urological Association guidelines for treatment of localized prostate cancer, patients considering external beam radiation should know that higher radiation doses may reduce the risk for cancer recurrence and improve survival outcome.

Brachytherapy is an outpatient technique that implants radioactive "seeds" directly into the prostate. Implants can be temporary or permanent. Temporary implants are usually accompanied by external beam radiation. This procedure requires more skill than external beam radiation therapy and, even with experienced doctors, the distribution of radioactive seeds is uneven in 15% of cases, increasing the risk for insufficient doses.

Computerized systems are being developed to help oncologists optimize seed placement and allow precise treatment for each patient and higher radiation doses. Eventually, it could improve tumor control, reduce side effects, and cut costs.

It is common for PSA levels to temporarily rise, or "bounce," following seed implantation without it being a signal for cancer recurrence. This effect can produce anxiety and can interfere with the diagnosis of true recurrence.

Candidates. Studies suggest that brachytherapy is useful for select patients, specifically those with prostate volumes less than 60 mL and who have early-stage prostate cancer (T1 or T2 tumors, a Gleason grade lower than 7, and PSA levels below 10 ng/mL). It may be beneficial in patients with inflammatory bowel disease or with cancer close to the bowel. Poorer candidates for brachytherapy include men who have had TURP and patients with advanced cancer, high-grade tumors, or very enlarged prostate glands.

The side effects of radiation therapy include most of those of surgery, but the risks for impotence and incontinence are considerably lower. A 2000 study concluded that adjuvant radiation therapy (given right after surgery) in moderate doses does not increase the risk for long-term urinary incontinence or sexual dysfunction beyond that of surgery alone.

Gastrointestinal Complications. Complications in the gastrointestinal are common. Short-term effects include nausea and loss of appetite. Diarrhea is a very common side effect and can last for the duration of therapy. It is usually treated with Lomotil. A few patients have diarrhea flare-ups for years afterwards. Less than 1% suffer more serious intestinal problems.

There is potential for injury to the rectum with brachytherapy. Ulcers in the rectum occur in more than 10% of patients, but the risk decreases with greater experience in the technique.

Urinary Problems. The risk for incontinence is about 7 - 20%. Patients treated with radiation may experience a painful, but usually temporary, urinary tract inflammation. About 10 - 15% of patients develop a long-term urgent and frequent need to void their bladder. Brachytherapy carries a lower risk for urinary incontinence.

Scarring and narrowing of the urinary tract (stricture) may occur, particularly in men who had TURP performed within a short time before radiation treatment. In such men, radiation treatments should be delayed by 4 - 6 weeks. If the prostate has been injured or damaged or the bladder is easily irritated, side effects with brachytherapy may actually be worse than with other procedures.

Impotence. In a 2003 review, the risk for impotence following radiotherapy varied from 25% with brachytherapy to 45% with external beam radiotherapy. Still, very few studies on brachytherapy have lasted more than 2 years, so more research is needed.

Sildenafil (Viagra) may help many men experiencing impotence following radiation therapy for local prostate cancer. Early use of both alprostadil injections and sildenafil may be even more effective. Other treatments may also be useful. [See In-Depth Report #15: Erectile dysfunction.]

Investigators are testing radiation treatments that use a combination of neutrons and protons (mixed-beam) or proton beams rather than the standard proton radiation therapy. Intensity-modulated radiation therapy is a promising technique that delivers different doses to multiple target areas using images of specific regions.

High-Intensity Focused Ultrasound (HIFU). Studies are reporting promising results with an intensive ultrasound procedure called transrectal high-intensity focused ultrasound (HIFU). It allows for very precise minimally invasive removal of tissue in local prostate cancers. It may eventually prove to be an alternative to radiation therapy. More research, with long-term follow up, is needed.

Radiofrequency. Radiofrequency is being used to heat and destroy the prostate. Early studies suggest that this is a promising approach.

Options if Treatments Fail

Rising PSA Levels. If prostate cancer has been eliminated, PSA levels should drop to 0.5 ng/mL or less after treatment. A sudden rise or persistently elevated PSA levels after treatment are often indications that prostate cancer persists:

• If PSA levels are above 2.0 ng/mL, then cancer is most likely still present.
• If PSA levels are between 0.5 - 2.0 ng/mL, the situation is less clear. One study indicated that measuring free PSA may help determine the status of the cancer in such patients. An average free PSA of 27% indicated that cancer had been eliminated, while an average of 15% meant that cancer was still present.

Note: It is common for PSA levels to temporarily rise following radiation seed implantation without signaling cancer recurrence.

Rising PSA levels do not necessarily mean that the cancer has spread or even that the cancer will recur during a man's lifetime. An actual cure is still possible if the cancer is localized within the prostate. In one study, 64% of patients with rising PSA levels after surgery still had cancer confined to the prostate. Indications of a poorer outlook in this study included:

• Cancer penetration of the prostate capsule
• Positive surgical margins (microscopic evidence of cancer cells at the very edge of the resected specimen)
• Invasion of nearby vessels or lymph nodes

Still, among the men in the study, after 7 years only 3% of patients had died of prostate cancer. After 15 years, only 19% had evidence of recurrence. Other markers for persistent cancer are under investigation. For example blood tests that show low levels of acid phosphatase (ACP) before treatments may predict a higher chance for recurrence-free survival.

Treatment for recurring cancer is not always clear-cut. If the cancer recurs locally, cure may still be possible:

• Surgery and androgen deprivation therapy may be considered for patients who were first treated with radiation.
• For patients who were initially treated with surgery, radiation or androgen deprivation therapy are both options.

If the disease has already spread or if the doctor suspects that it may have spread, the patient is typically given androgen deprivation therapy. Chemotherapy drugs in combination with hormonal drugs are being investigated for patients who fail surgery or radiation.

A 2005 study in the Journal of the American Medical Association suggested three factors that may help doctors and patients decide if additional treatment is needed if cancer recurs after surgery:

• How quickly PSA levels double after surgery (shorter time equals higher risk)
• How quickly the cancer recurred after surgery (shorter time equals higher risk)
• Gleason score (higher score suggests more aggressive tumors and greater risk)

Patients at high risk are more likely to die from the recurrent cancer and should be considered for additional treatments. Patients at low risk face a lower likelihood of death from prostate cancer and probably do not require more treatment. The study found that for patients at low risk, the time to death after cancer recurrence was very long, generally lasting more than 16 years.

Androgen Deprivation Therapy. Androgen deprivation therapy, also called androgen suppression therapy or hormone therapy, involves blocking the effect of male hormones such as testosterone through medical (drugs) or surgical castration. Androgen suppression therapy is not recommended as a first-line approach for most men with localized prostate cancer. It is usually given to patients with recurrent, progressive, or advanced prostate cancer. It may also be given for a relatively brief time in combination with external beam radiation.

Although androgen deprivation therapy slows the growth of most prostate cancers, it can have serious side effects. The American Society of Oncology’s (ASCO) 2007 guidelines do not recommend the early use of hormone therapy. However, ASCO does recommend that patients start therapy once they begin to experience cancer symptoms. Patients who defer therapy should have regular doctor visits every 3 - 6 months to monitor their condition.

Salvage Prostatectomy. Salvage prostatectomy is sometimes performed after unsuccessful radiation treatment if the cancer is still local. The odds of the procedure's success are only 10 - 64%. Many experts recommend against salvage prostatectomy in most cases of radiation failure. Severe complication rates for salvage prostatectomy are very high: 10 times that of men who have not had radiation. For example, incontinence after salvage prostatectomy is often untreatable with medications, collagen implants, or other standard treatment measures.

Salvage Cryosurgery. Salvage cryosurgery may be effective in certain patients who fail external beam radiotherapy. The best candidates are those with Stage II cancer or less and PSA levels below 10 ng/mL.

Adjuvant and Salvage Radiation. Radiation is proving to help patients who still show detectable levels of PSA after surgery (generally 2 ng/mL or less). It may even be useful years after surgery if PSA levels rise. Depending on timing, radiation after treatment failure is referred to as either:

• Adjuvant radiation is radiation therapy performed within 6 months after radical prostatectomy. One area of controversy is whether to use adjuvant radiation after surgery on patients whose PSA levels are very low or undetectable but who have other test results that indicate the cancer is likely to spread. Patients with adverse findings and low PSA have to weigh the potential complications of radiation therapy against the odds of recurrence without it, which are about 20 - 30%. A small 2006 study found that adjuvant radiation worked much better than salvage radiation for men with advanced (stage III or IV) local prostate cancer. However, a 2007 study indicated that adjuvant radiation in men with advanced cancer may reduce the risk of cancer recurrence but does not improve length of survival.
• Salvage radiation is radiation therapy more than 6 months after surgery. A 2004 study suggested that salvage radiation could be more beneficial than previously thought, even for men with aggressive prostate cancer. Researchers studied 501 men who had undergone radical prostatectomy (surgical removal of the prostate gland) and subsequently received radiation treatment for recurrent cancer (as indicated by rising PSA levels). Men with lower Gleason scores and lower PSA levels benefited the most from salvage radiation. However, even men with higher-grade cancers were able to delay metastatic cancer progression as long as they received radiation at an early stage while their PSA levels were relatively low (less than 2.0 ng/mL).

Other Treatments

Male hormones (called androgens), particularly testosterone and dihydrotestosterone, determine male secondary sex characteristics and stimulate prostate cell growth. When prostate cells, both healthy and cancerous, are deprived of androgens, they no longer proliferate and eventually die.

Androgen deprivation therapy (also called androgen suppression therapy or hormone therapy) uses drugs or surgery (orchiectomy) to suppress or block male hormones (androgen) -- particularly testosterone and dihydrotestosterone -- that stimulate the growth of prostate cells. Androgen deprivation therapy is used for advanced and metastatic cancer and may be used if treatment for localized prostate cancer has failed and cancer recurs (as indicated by rising PSA levels). Side effects can include decreased bone density, decreased muscle mass, hot flashes, depression, fatigue, weight gain, enlarged breasts, and high cholesterol levels. Evidence also indicates that androgen deprivation therapy increases the risk for diabetes and death from heart disease.

There has been some debate about when androgen deprivation therapy should be initiated. In 2007, the American Society of Clinical Oncology (ASCO) published clinical guidelines for androgen deprivation therapy in patients with recurrent, progressive, or advanced prostate cancer. The guidelines recommend that hormone therapy should, in general, be delayed until patients begin to experience symptoms from their cancer. However, when therapy is deferred, patients should regularly visit their doctors every 3 - 6 months for careful monitoring of their condition.

ASCO recommends either removal of both testicles (bilateral orchiectomy) or injections with luteinizing hormone-releasing hormone (LHRH) as initial androgen deprivation treatments. Combining nonsteroidal antiandrogen drug therapy with orchiectomy or LHRH may also be considered.

Doctors vary widely on their opinions of androgen deprivation therapy. A 2006 study found that the decision to use hormonal therapy depends more on a patient’s urologist than on the patient’s tumor or other factors.

Androgen deprivation therapy includes:

Hormonal Drugs. The primary drugs used for suppressing androgens are called luteinizing hormone-releasing hormone (LH-RH) agonists.

Orchiectomy. Orchiectomy is the surgical removal of the testicles. It is the single most effective method of reducing androgen hormones, but it is considered an extreme procedure. Studies do not indicate that it significantly improves survival rates. Orchiectomy plus radical prostatectomy may delay progression in patients with cancers that have spread only to the pelvic lymph nodes. Combining orchiectomy with antiandrogen drug therapy adds a modest benefit.

The median survival rate after the operation is about 55% over a 40-month period. An estimated 25% of patients survive 5 years or more. Nevertheless, orchiectomy, although irreversible, may produce fewer adverse effects than hormonal drugs, and interestingly, many patients report significantly higher quality of life after orchiectomy than those who opt for hormonal treatment, particularly total androgen ablation. Because orchiectomy is irreversible, about 75% of patients with advanced prostate cancer choose hormonal therapy to block androgens. Like all androgen deprivation therapies, orchiectomy increases the risk for osteoporosis.

Many men can still achieve erection after orchiectomy, but there is almost always a decline in sexual drive. Men who cannot achieve erection may be candidates for a penile implant. Patients do not experience a reversal of sex characteristics; the voice does not change and body hair is not affected.

Androgen Deprivation Therapy Before or With Radiation. Hormonal drugs combined with radiation therapy may improve survival rates in moderate- or high-risk groups. Patients may need to take these drugs long-term to improve outcomes. Hormonal drugs before radiation (neoadjuvant therapy) may be helpful in shrinking enlarged glands so that brachytherapy (radiation implants) can be used.

An important study published in 2004 in the Journal of the American Medical Association found that for men with localized prostate cancer, a 6-month course of hormone therapy combined with radiation treatments produced greater survival rates than radiation treatment alone. Standard medical practice has generally indicated that hormone therapy should be administered for 3 years; the JAMA study suggests that a shorter regimen may be equally beneficial for some patients and may help reduce the side effects that typically accompany androgen-suppressing drugs.

Androgen Deprivation Therapy Before or After Surgery. Some studies suggest benefits from using hormone therapy before surgery (neoadjuvant therapy) to reduce the tumor size, although it is not clear yet if this approach has survival benefits. Hormonal treatment may be useful after surgery in men who have high-grade tumors or tumors that have invaded the semen-carrying vessels or lymph nodes. Such men have a risk for failure after surgery of 50 - 80%.

The primary drugs used for suppressing androgens are called luteinizing hormone-releasing hormones (LHRH) agonists. They include:

• Leuprolide (Lupron, Leuprogel). Studies report that disease progression is prevented in 72% of men taking daily leuprolide and up to 89% of those taking monthly injections. Certain men, however, may not respond to injections. Drug delivery using implants is under investigation.
• Goserelin (Zoladex). Partial responses of 60 - 80% have been reported. A controlled release formulation has been developed that increases the time between injections from 4 weeks to 3 months.
• Buserelin.

LHRH drugs block the pituitary gland from producing hormones that stimulate testosterone production. Patients must have injections of LHRH agonists for the rest of their lives.

Testosterone and PSA Surges. Treatment with LHRH agonists produces a testosterone surge in the first week, which may actually intensify symptoms. After this phase, testosterone levels drop to near zero. Leuprogel, a newer leuprolide, may pose a lower risk for this effect. Researchers are investigating other drugs, such as GnRH antagonists, that do not produce this surge.

LH-RH agonists can also cause PSA levels to rise temporarily. Administering flutamide, a drug known as an antiandrogen, for 2 weeks prior to LH-RH agonists may not only prevent PSA surge but also induce early declines in PSA levels.

Side Effects. Side effects include hot flashes and occasionally nipple and breast tenderness.

Gonadotropin-releasing hormone (GnRH) stimulates the pituitary gland to release luteinizing hormone-releasing hormones (LHRH). GnRH antagonist drugs such as abarelix (Plenais) and histrelin (Vanta) block this action. They have two advantages over LHRH agonists:

• They do not cause the same testosterone surge that can temporarily worsen cancer symptoms.
• They seem to reduce testosterone levels more quickly.

Anti-androgens are drugs used to block the effects of testosterone. They are used alone or in maximal androgen blockage (MAB), in which they are combined with LHRH agonists or orchiectomy to completely block androgen hormones. Anti-androgens are either steroidal or nonsteroidal.

Nonsteroidal Anti-androgens. Nonsteroidal anti-androgen drugs include:

• Flutamide (Eulexin, Drogenil). Flutamide has produced extended response in some patients. Side effects may include diarrhea and liver damage, which has been fatal in rare cases; liver function must be monitored closely.
• Nilutamide (Nilandron). Nilutamide is associated with reversible interstitial pneumonitis, nausea, alcohol intolerance, and visual disturbances.
• Bicalutamide (Casodex). Bicalutamide is effective and appears to have fewer severe side effects than other anti-androgens, including loss of sexual interest, osteoporosis, visual disturbance, and interstitial pneumonia. This drug is proving to have survival rates equal to those of maximal androgen blockage.

Steroidal Antiandrogens. Steroidal antiandrogens act like female hormones and include:

• Megestrol uppresses androgen production, but incompletely, and is generally not used as initial therapy.
• Cyproterone combined with estrogen may prevent the testosterone surge that occurs with LH-RH agonists.

Men often experience fatigue, loss of energy, and emotional distress from androgen suppression treatment. Hormonal therapy may significantly impair quality of life, particularly in men who had no symptoms beforehand and whose cancer has not metastasized. Common side effects of androgen suppression drugs include:

• Osteoporosis, the loss of bone density. This risk is higher with orchiectomy than with androgen suppressants. Some androgen suppressants, such as bicalutamide, may cause less bone loss. The use of estrogens may actually be bone protective. A number of medications, especially bisphosphonates, are available to help prevent or reduce bone loss.
• Diarrhea
• Loss of muscle mass
• Psychological disturbances
• Fatigue
• Loss of sexual drive and sexual dysfunction
• Swelling of the breasts (gynecomastia)
• Nausea and vomiting
• Hair loss
• Anemia

In addition, there is growing evidence that androgen deprivation therapy increases the risks for diabetes and heart disease.

Prostate cancer that does not respond to hormonal treatment is called hormone-resistant, or hormone-refractory, cancer. There are various drug treatments for hormone-resistant cancer:

Docetaxel and Other Chemotherapy. Chemotherapy drugs for prostate cancer include docetaxel (Taxotere), mitoxantrone (Novantrone), estramustine (Emcyt), and various platinum-based drugs, such as carboplatin. These drugs are often combined with other cancer drugs (such as 5-fluorouacil) or corticosteroids (such as prednisone).

Docetaxel-based drug regimens are emerging as the main chemotherapy treatment for hormone-refractory prostate cancer. In 2004, the FDA approved docetaxel injection in combination with prednisone for treatment of patients with hormone-resistant prostate cancer. Patients who received this drug combination survived on average 2.5 months longer than patients who received mitoxantrone and prednisone. Another 2004 clinical trial found that a docetaxel and estramustine combination worked better than mitoxantrone and prednisone for advanced resistant prostate cancer. Side effects can be serious and may include gastrointestinal problems (nausea, vomiting, or diarrhea), fatigue, low blood cell counts, and increased risk for blood clots.

Researchers are continuing to investigate docetaxel combinations and compare them to other chemotherapy regimens. A large 2006 study reported that docetaxel and prednisone worked better than mitoxantrone plus prednisone in improving quality of life, pain relief, and survival. Docetaxel is also being investigated in combination with vitamin D-related drugs. A 2006 trial found that men with advanced prostate cancer who took docetaxel plus high-dose vitamin D (calcitriol) lived about 8 months longer than men who received docetaxel and placebo. Calcitriol also appeared to protect against docetaxel’s side effects, especially gastrointestinal problems and blood clots.

Doctors are also studying other ways to help patients cope with docetaxel’s side effects. Research presented at the 2006 Prostate Cancer Symposium suggested that patients may be able to take periodic breaks from docetaxel treatment instead of having continuous therapy. In the study, patients with advanced prostate cancer were given the option of suspending docetaxel treatment if their PSA levels improved within a certain range. Researchers found that patients were able to take 16-week breaks and still show improvement once they resumed treatment. This approach may work best for patients who experienced a good initial response to docetaxel.

Bisphosphonates. These drugs prevent bone loss and reduce bone pain in metastasized cancers. They are of particular interest because they may inhibit prostate cancer cell growth in the bone. The bisphosphonates showing most promise in prostate cancer are newer drugs called nitrogen-containing bisphosphonates (pamidronate, zoledronic acid).

Immunotherapies. The prostate organ offers special possibilities for genetic therapies because it contains highly specific antigens (factors that the immune system can target). There are a number of approaches currently under investigation, including:

• Genetically designed vaccines (Provenge, Gvaz, JBT 1001) inject factors into prostate cancer cells that trick the immune system into attacking the cancer cells.
• Antisense therapy for prostate cancer blocks expression of a protein called BCL-2, which tends to be genetically overexpressed in some patients with androgen-independent prostate cancer. This protein prevents apoptosis (a natural process by which all cells, including cancer cells, self-destruct).
• Monoclonal antibodies (MAbs) are genetically designed immune factors that target foreign compounds called antigens for attack by the immune system. Monoclonal antibodies are being designed to target prostate-specific antigens.

Angiogenesis 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 ). The spread of new blood vessels is controlled by compounds called growth factors, which may be important in cancer cell proliferation. Researchers are interested in drugs that turn off these growth factors or their receptors, such as epidermal growth factor receptor (EGFR). In doing so, the drugs may be able to cut off cancer's life blood. Gefitinib (Iressa) and erlotinib (Tarceva) are angiogenesis inhibitors that target receptors of epidermal growth factors called tyrosine kinase. They are being used in lung cancer and are being investigated in a number of other cancers, include prostate cancer. Various drugs that inhibit angiogenesis in other ways (thalidomide, endostatin) are also under investigation.

Ketoconazole. Ketoconazole is an antifungal drug that blocks an enzyme that stimulates production of testosterone. It is effective in high doses but can have severe gastrointestinal effects, mainly nausea and anorexia. Long-term use can result in impotence, itchy skin, nail changes, and suppression of stress hormones. One center reported a consistent PSA response in more than 60% of patients who had failed other androgen deprivation treatments.

Aromatase Blockers. Aminoglutethimide (Cytadren) and similar drugs block aromatase, an enzyme important in estrogen production. Because the female hormone estrogen plays such a major role in the development of breast cancer, some experts think that blocking the small amount of estrogen found in men may also affect prostate cancer. Side effects include drowsiness and skin rash.

Atrasentan. Atrasentan is known as an ET(A)-receptor antagonist. It is showing promise in reducing bone loss and delaying progression of prostate cancer in men with advanced disease that no longer responds to hormone therapy. Side effects are relatively mild.

Resources

• www.cancer.gov -- National Cancer Institute
• www.cancer.org -- American Cancer Society
• www.asco.org -- American Society of Clinical Oncology
• www.plwc.org -- People Living with Cancer
• www.prostatecancerfoundation.org -- Prostate Cancer Foundation
• www.fightprostatecancer.org -- National Prostate Cancer Coalition
• www.urologyhealth.org -- Urology Health
• www.nccn.org -- National Comprehensive Cancer Network
• www.cdc.gov/cancer/prostate -- CDC Cancer Prevention and Control
• www.psa-rising.com -- PSA Rising: Prostate Cancer Survivor Info
• www.ustoo.org -- Us Too! Prostate Cancer Education and Support
• www.cancer.gov/clinicaltrials -- Find clinical trials

References

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Gudmundsson J, Sulem P, Manolescu A, Amundadottir LT, Gudbjartsson D, Helgason A, et al. Genome-wide association study identifies a second prostate cancer susceptibility variant at 8q24. Nat Genet. 2007 May;39(5):631-7. Epub 2007 Apr 1.

Haiman CA, Patterson N, Freedman ML, Myers SR, Pike MC, Waliszewska A, et al. Multiple regions within 8q24 independently affect risk for prostate cancer. Nat Genet. 2007 May;39(5):638-44. Epub 2007 Apr 1.

Keating NL, O'Malley AJ, Smith MR. Diabetes and cardiovascular disease during androgen deprivation therapy for prostate cancer. J Clin Oncol. 2006 Sep 20;24(27):4448-56.

Lawson KA, Wright ME, Subar A, Mouw T, Hollenbeck A, Schatzkin A, et al. Multivitamin use and risk of prostate cancer in the National Institutes of Health-AARP Diet and Health Study. J Natl Cancer Inst. 2007 May 16;99(10):754-64.

Leman ES, Cannon GW, Trock BJ, Sokoll LJ, Chan DW, Mangold L, et al. EPCA-2: a highly specific serum marker for prostate cancer. Urology. 2007 Apr;69(4):714-20.

Loblaw DA, Virgo KS, Nam R, Somerfield MR, Ben-Josef E, Mendelson DS, et al. Initial hormonal management of androgen-sensitive metastatic, recurrent, or progressive prostate cancer: 2006 update of an American Society of Clinical Oncology practice guideline. J Clin Oncol. 2007 Apr 20;25(12):1596-605. Epub 2007 Apr 2.

Thompson I, Thrasher JB, Aus G, Burnett AL, Canby-Hagino ED, et al. Guideline for the management of clinically localized prostate cancer: 2007update. J Urol. 2007 Jun;177(6):2106-31.

Thompson IM, Tangen CM, Paradelo J, Lucia MS, Miller G, Troyer D, et al. Adjuvant radiotherapy for pathologically advanced prostate cancer: a randomized clinical trial. JAMA. 2006 Nov 15;296(19):2329-35.

Walter LC, Bertenthal D, Lindquist K, Konety BR. PSA screening among elderly men with limited life expectancies. JAMA. 2006 Nov 15;296(19):2336-42.

Yeager M, Orr N, Hayes RB, Jacobs KB, Kraft P, Wacholder S, et al. Genome-wide association study of prostate cancer identifies a second risk locus at 8q24. Nat Genet. 2007 May;39(5):645-9. Epub 2007 Apr 1.

Review Date:
6/27/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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