Prostate specific antigen in the diagnosis and treatment of adenocarcinoma of the prostate. I. Untreated patients.

Serum prostate specific antigen levels were determined (Yang polyclonal radioimmunoassay) in 230 men with untreated adenocarcinoma of the prostate after careful clinical staging. Prostate specific antigen was directly proportional to advancing clinical stage, statistically failing to distinguish only between consecutive stages B2 and B3, and between stages C and D1. Serum prostatic acid phosphatase by radioimmunoassay was unable to distinguish men with stages C plus D1 from B2 plus B3 disease but it could distinguish stages C plus D1 from A2 plus B1 (p equals 0.015). Serum prostate specific antigen was directly proportional to increasing Gleason score. In 59 untreated patients multiple prostate specific antigen values were obtained during a mean followup of 10 months. Of the patients 81 per cent showed a steady increase with time, including 91 per cent of men with clinical stage B2 or greater disease. The rate of increase accelerated with time, and correlated with advancing tumor stage and increasing serum concentration of prostate specific antigen. The rate of increase of prostate specific antigen in clinical stages A and B cancer patients suggested a doubling time of at least 2 years. Serum prostate specific antigen was significantly decreased by transurethral resection of prostatic tissue in patients with cancer, as has been shown previously in patients with benign prostatic hyperplasia.