Prostate cancer is the most common cancer in men, and the second leading cause of cancer death among men in the U.S. More than 180,000 men in the U.S. will be diagnosed with prostate cancer this year alone, and more than 40,000 will die of the disease. Eighty percent of men who reach age 80 have prostate cancer. Prostate cancer is a malignant tumor that usually begins in the outer part of the prostate. In most men, the cancer grows very slowly. In fact, many men with the disease will never know they had the condition.

Early prostate cancer is confined to the prostate gland itself, and the majority of patients with this type of cancer can live for years with no problems. Prostate cancer is characterized by both "grade" and "stage." The size and extent of the tumor determine its stage. Early stage prostate cancer, Stages T1 and T2, are limited to the prostate gland. Stage T3 prostate cancer has advanced to tissue immediately outside the gland and may cause urinary problems. Stage T4 prostate cancer has spread to other parts of the body.