Prostate cancer is common (186 000 new US diagnoses in 2008), causing more than 28 000 deaths per year.1 Treatment of clinically detected prostate cancer is effective in reducing prostate cancer mortality in men younger than 65 years but not in older men.2 However, treatment of prostate cancer is associated with considerable morbidity; approximately 50% of men will have impotence, incontinence, or both after treatment, and a few will die as a result of initial treatment.3