An estimated 5-10% of prostate cancer is due to hereditary causes. Among men with early prostate cancer, a hereditary cause is likely in up to a third of cases before age 60 and in almost half of men diagnosed with prostate cancer at age 55 or less. Studies have found around a two- to three-fold increased rate of prostate cancer in close relatives of men with the disease. Hereditary prostate cancer is likely in a family if there are three cases of prostate cancer in close relatives; or three affected generations (on either mother's or father's side); or two relatives with prostate cancer before age 55.
Studies suggest that hereditary prostate cancer is likely to be caused by several different genes instead of a single gene. At least four other genes have been reported, including one thought to increase the risk of both prostate and brain tumors. Other genes known to increase the risk of other cancers, such as breast cancer, also may be linked to increased prostate cancer risk. Common variations in certain genes also may increase susceptibility to prostate cancer, including one gene linked to male sex hormones. Since no clear cause has been identified for the majority of hereditary prostate cancer, genetic testing, as of 2001, is typically done through research studies.
Prostate cancer is the most common cancer among men in the United States, and is the second leading cause of cancer deaths. The American Cancer Society estimates that in 2001, 198,100 new cases of prostate cancer will be diagnosed, and it will cause 31,500 deaths. One in six men in the United States will be diagnosed with prostate cancer. Prostate cancer affects black men about twice as often as it does white men, and the mortality rate among African Americans is also higher. African Americans have the highest rate of prostate cancer in the world. The prostate cancer rate varies considerably around the world. The highest rates are in North America and Western Europe, whereas the rates are moderate in Africa and lowest in Asia. It is unclear what roles genetics, diet, economics, and health care access play in these rates.
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Author Info: L. Fleming Fallon Jr., MD, DrPH, The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Nursing and Allied Health, 2002 |