Prostate cancer screening: the continuing controversy.

Prostate cancer is the second most common cancer in men, with a lifetime prevalence of 17 percent. Prostate cancer symptoms generally occur in advanced stages, making early detection desirable. Digital rectal examination and prostate-specific antigen testing are the most commonly used screening tools. The goal of screening is to detect clinically significant prostate cancers at a stage when intervention reduces morbidity and mortality; however, the merits and methods of screening continue to be debated. Prostate-specific antigen levels may be less than 4 ng per mL in 15 to 38 percent of men with cancer, indicating a high false-negative rate. The positive predictive value of the prostate-specific antigen test is approximately 30 percent; therefore, less than one in three men with an abnormal finding will have cancer on biopsy. These limitations of the prostate-specific antigen test have led to variations designed to improve its accuracy (e.g., age- and race-specific cutoffs, free prostate-specific antigen tests); however, none of these modifications have been widely adopted because of unclear benefits. Although treatments have improved in the past two decades, therapy for prostate cancer is not benign and may lead to urinary incontinence, sexual dysfunction, or bowel dysfunction. New evidence affecting screening recommendations continues to accumulate, and two large randomized controlled trials of screening will be completed in the next few years. Current guidelines recommend an individualized, targeted, patient-centered discussion to facilitate a shared decision about screening plans.