What causes prostate cancer? What are some symptoms?

Q: What is prostate cancer?

A: Prostate cancer develops in the prostate gland, a walnut-size organ that surrounds the bottom portion of the male bladder and the first inch of the urethra. The prostate produces seminal fluid, which nourishes and transports sperm.

Q: How common is prostate cancer?

A: About 1 in 6 men will get prostate cancer in their lifetime, and 1 in 34 will die of it, according to the American Cancer Society. In 2005, about 232,000 new cases will be diagnosed and about 30,350 men will die of the disease, the society estimates. Prostate cancer is second only to lung cancer in cancer mortality for men.

Q: What causes prostate cancer?

A: No one really knows. But research has shown that certain factors increase the risk. Those include:

• Being over 50.

• Being African American (70 percent more likely to get the disease and twice as likely to die of it).

• Having a father or brother with the disease, especially if they developed it at a young age.

• Having a high-fat diet and eating few fruits and vegetables.

Q: What are signs and symptoms of the disease?

A: Early prostate cancer usually doesn't carry any signs or symptoms. It is usually found with a blood test for PSA (prostate-specific antigen), produced by the prostate, and a DRE (digital rectal exam) in which the physician feels the prostate through the rectum wall for abnormalities. If these suggest cancer, the doctor may perform a biopsy, in which prostate tissue samples are removed by a needle, then examined in a lab.

Many physicians recommend an annual PSA and DRE beginning at age 50, or younger for men at higher risk for the disease.

Some men with advanced prostate cancer may have a slow urinary stream or need to urinate more often, though those problems could also be caused by benign prostatic hyperplasia, a swelling of the prostate that often occurs in older men.

Other symptoms of advanced prostate cancer can include bloody urine, erectile dysfunction, pain in the hips, spine or ribs, and weakness or numbness in the legs or feet.

Q: Does prostate cancer rapidly spread to other parts of the body?

A: Usually, it grows slowly and remains confined to the prostate. But sometimes it does spread quickly. Even with modern tests, it is often difficult to tell whether the cancer is more aggressive.

Sources: American Cancer Society, Mayo Clinic