Prostate cancer is a life-threatening tumor that develops in the prostate.

The prostate is a gland in men within the pelvis at the base of the penis. It surrounds the bottom part of the bladder and urethra. (The urethra is the tube that carries urine from the bladder to the outside.) The prostate produces a fluid that nourishes sperm and is ejaculated with semen, the fluid that carries sperm.

Prostate cancer is the most common cancer in American men. It is the second most common cause of cancer death (after lung cancer). Two to three times more African-American men get prostate cancer than white men.

The risk for prostate cancer increases with age. It usually occurs after age 50.

It is not known how prostate cancer occurs. There may be a relationship to increased fat in the diet (as there is with breast cancer). Under continuing investigation are the possible effects of:

• Previous vasectomy
• Cadmium intake
• Exposure to high levels of male hormones
• Cigarette smoking.

None of these factors has been definitely linked to prostate cancer. Research continues.

Prostate cancer often has no symptoms. When there are symptoms, they can be similar to the symptoms of noncancerous growth of the prostate (benign prostatic hypertrophy, or BPH, which normally occurs as men get older.) The symptoms of a tumor in the prostate are also often the same as the symptoms of an infection of the prostate or other blockage.

The symptoms of prostate cancer vary depending on the size of the tumor and how far the cancer has spread. Possible symptoms are:

• The need to urinate frequently and with urgency
• Difficulty beginning a stream of urine
• Decreased force in the stream of urine
• Increased need to urinate at night
• Inability to urinate
• Bone pain or back pain if the cancer has spread.

Because prostate cancer may not have symptoms, the disease is usually found as part of a routine physical exam or an exam for some other health problem. Often it is diagnosed when a procedure called a transurethral prostatectomy (TURP) is performed. (TURP is a treatment for BPH.)

Prostate cancer can sometimes be felt during a rectal exam. The rectal exam is a critical part of your physical exam after age 40 to check for colon, rectal, and prostate cancer.

A lab test is now available to help detect prostate cancer. It is a blood test for prostate specific antigen, or PSA. Like many cancer screening tools, it is not perfect and can give misleading results. For this reason there is some controversy about when PSA tests should be done. The test is most useful when done in conjunction with a physical exam and medical history.

When the rectal exam or PSA result is abnormal, your doctor may recommend a biopsy. Biopsies are usually done while your doctor views the prostate with a transrectal ultrasound. A sample of the abnormal area in the prostate is removed and examined under a microscope. If the biopsy is normal, your doctor will tell you how often you should have an exam and PSA testing based on your age, family history, and African heritage.

Treatment depends on how large the tumor is, whether it has spread to other parts of your body, and your overall physical condition. Some of the treatment options are:

• Surgical removal of the prostate, called radical prostatectomy, which results in loss of ejaculation with orgasm and sometimes impotence (inability to have or keep an erection) or incontinence (trouble holding your urine)
• Radiation therapy, which may cause the urethra, rectum, and anus to become inflamed and may also lead to long- term problems such as diarrhea and impotence
• Treatments to eliminate the stimulating effect of testosterone (male hormone) on the prostate cancer; for example, by removing the testicles or prescribing female hormones
• Chemotherapy in selected situations.

Have regular checkups with your doctor. Rectal exams of the prostate can be embarrassing and slightly uncomfortable, but it is important for men over age 40 to have one every year. The yearly rectal exam also screens for cancers of the colon and rectum. The American Cancer Society recommends that all men over age 50 also have their serum PSA level checked every year, particularly if they are at high risk for prostate cancer (African Americans and men with a family history of prostate cancer).

After treatment your doctor will recommend regular checkups to look for any return of cancer. It is important to follow your doctor's instructions, so that your body's response to treatment can be monitored and any recurrence will be spotted early and treated.