I. Introduction
Prostate cancer is the second-leading cause of cancer deaths in American men. The American Cancer Society predicted that in 2002, 189 000 men would be diagnosed with prostate cancer and about 30 200 would die [1]. When prostate cancer is diagnosed in its early stages, it is usually curable; and the treatment is often effective even in its later stages. Therefore, the decision of when, how, and on whom to apply a diagnostic procedure is very important [2].