[Natural follow-up of prostate cancer and consequences for early detection]

The natural history of prostatic cancer has been regarded as unpredictable for a long period of time. The discrepancy between histologically identifiable (50%) and clinically diagnosed carcinomas (8%) led to the term of 'latent' prostatic cancer and to a considerable diagnostic and therapeutic dilemma. Based on our previous studies showing that biological aggressiveness of prostatic cancer is a direct function of tumor volume and that tumor volume and serum-PSA are proportional, we evaluated two basically different groups of patients. The first group consisted of 43 patients with untreated carcinomas of the prostate followed with serial PSA determinations. The exponential (log-linear) rise in PSA led us to the conclusion of an exponential tumor growth rate. The doubling time of organ-confined tumors was three to four years and became shorter with higher clinical stages and poorly differentiated histological grades. The second group consisted of 139 patients who underwent cystoprostatectomy for bladder cancer and had no evidence for simultaneously identifiable prostatic cancer. In 55 Patients (40%) unsuspected prostatic cancer was found in the specimen; the volume distribution of these carcinomas was exponential. Eleven of the 139 men (7.9%) had a prostatic cancer > or = 0.5 cc, corresponding to the 8%-risk for a man being diagnosed within his lifetime with a clinically significant carcinoma of the prostate. We conclude that the other 44 carcinomas < 0.5 cc will never reach clinical significance due to their small size and their long doubling time; in this sense they can be considered 'latent'.(ABSTRACT TRUNCATED AT 250 WORDS)