Reported family history of cancer in 1,271 prostate cancer cases and 1,909 controls.

Prostate cancer risk has been associated with a family history of the disease. A two- to three-fold increase in risk has been observed in several studies. Details concerning modification of this risk by age, type of familial history of prostate cancer, and possible involvement of history of cancer at other sites have been less well documented. This case-control study of 1,271 prostate cancer patients and 1,909 control subjects admitted to Roswell Park Cancer Institute in Buffalo, NY, found age-adjusted increased risk associated with reporting a history of prostate cancer in a father (RR = 2.3, 95% Cl 1.4-3.3) or brother (RR = 2.5, 95% Cl 1.6-3.9). Subjects with both a father and brother affected had a 6.5-fold (95% Cl 1.4-30.5) increased risk of prostate cancer. Greater risk were observed at younger ages of diagnosis. Risks associated with reporting a father or a brother affected were not significantly elevated for patients over age 70 at diagnosis. No significant differences in patients reporting histories of cancer other than prostate cancer were observed regardless of relationship, age at diagnosis, or type of cancer examined. These observations from a large cancer patient population may be useful when making recommendations for cost-effective prostate cancer screening and for directing investigators to the potentially most informative subjects.