Most men who get prostate cancer are in their seventies or older. Men with a family history of prostate cancer are at increased risk for the disease. Black men have higher incidence rates than white men, though incidence among white men is rising faster, probably as a result of intensified screening. Mortality rates among black men are twice as high as those of white men. This may be partly due to the fact that black men, on average, are diagnosed at later stages of disease than white men.
Prostate cancer is an important public health problem.
The decline in heart disease mortality in recent decades means that more men are living to older ages at which risk for prostate cancer is highest. Because the causes of the disease are largely unknown, risk factors are difficult to identify. The hormone dependence of prostate growth offers one possible avenue of intervention before cancer has a chance to develop. Finasteride works in treating benign prostate enlargement by altering the hormonal balance in the prostate. The PCPT is testing whether finasteride may prevent prostate cancer through the same hormonal mechanism.