Adenocarcinoma of the prostate is the most common of all male cancers in Western countries except for skin cancer and second only to lung cancer in mortality. Through the introduction of prostate-specific antigen (PSA) and transrectal ultrasonography with biopsy a few years ago, more and more prostate cancers have been diagnosed. However, the discrepancy between histologically identifiable carcinomas (40% in autopsy series and in cystoprostatectomy series for bladder cancer, respectively) and clinically diagnosed carcinomas (8% probability for a man being diagnosed within his entire life) has led to a considerable diagnostic and therapeutic dilemma. Prostate cancer was said to have an unpredictable natural course and selection criteria for radical prostatectomy and prognostic parameters in view of long-term follow-up were not well defined. The present monograph consists of four parts: a review on prostatic cancer in general, clinical studies on the natural history, clinical studies on selection criteria for curative surgery, and morphological and immunohistochemical investigations on various prognostic factors in radical prostatectomy specimens.