Epidemiology and natural history of benign prostatic hyperplasia.

Clinical manifestations of BPH include the symptoms, signs, and sequelae of urinary obstruction caused by the abnormal growth of non-malignant nodules that arise in a small region around the proximal segment of the prostatic urethra. Although the pathologic diagnostic criteria are relatively specific, clinical diagnostic criteria are much less specific, and no single BPH case definition has gained wide acceptance for use in epidemiologic studies.