Prostate Cancer Definition

Prostate cancer is one of the most widespread types of cancer in men. Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. The prostate is a part of the male reproductive system, which includes the penis, prostate, and testicles. The prostate is located just below the bladder and in front of the rectum. It is about the size of a walnut and surrounds the urethra (the tube that empties urine from the bladder). The job of the prostate is to produce fluid that makes up a part of semen. As men age, the prostate tends to increase in size. This can cause the urethra to narrow and decrease urine flow.

Not counting some forms of skin cancer, prostate cancer in the United States is—

• The most common cancer in men, no matter your race or ethnicity.
• The second most common cause of death from cancer among white, African American, American Indian/Alaska Native, and Hispanic men.
• The fourth most common cause of death from cancer among Asian/Pacific Islander men.
• More common in African-American men compared to white men.
• Less common in American Indian/Alaska Native and Asian/Pacific Islander men compared to white men.

More common in Hispanic men compared to non-Hispanic men.

Prostate Cancer Causes

The cause of prostate cancer is unknown, although it's likely that a combination of factors, including genetics, diet, ethnicity, hormones, and your environment, may play a part.

Some studies have shown a relationship between a high-fat diet and increased testosterone levels, which stimulate growth of the prostate. Some doctors think that testosterone replacement therapy might make existing prostate cancer grow faster, and men who use testosterone therapy may be more likely to develop prostate cancer than those with lower levels of the hormone. A genetic influence is suggested because prostate cancer tends to occur in men who are related to one another (see "Risk Factors" section). In addition, researchers have identified a gene that is associated with 30% of family-related prostate cancers.

Asian men tend to have a lower incidence of prostate cancer, while African-American men have one of the highest incidence rates in the world.

Prostate Cancer Risk Factors

The following factors may increase a man's risk for prostate cancer:

• Age -- prostate cancer is most common among men who are older than 55.
• Race -- African-Americans have a greater risk of developing prostate cancer than Caucasians who, in turn, have a greater risk than Native and Latin Americans.
• Family history of prostate cancer -- having a brother with prostate cancer makes a man 4.5 times more likely to develop the disease. Having a father with prostate cancer makes a man 2.3 times more likely to develop prostate cancer.
• High-fat diet -- foods rich in saturated fat may increase testosterone levels, which stimulates the growth of the prostate.
• Lack of exercise -- may increase the risk in men who eat a high-fat diet.