SIGNIFICANCE AND FUTURE OF PROSTATE-SPECIFIC ANTIGEN (PSA, Tandem) IN THE MASS SCREENING FOR PROSTATE CANCER

Abstract

The significance of prostate-specific antigen (PSA) measured with a Tandem PSA kit in 2230 serum samples examined by mass screening for prostate cancer was investigated.In 1985-1991, subjects were examined by digital rectal examination (DRE) and prostatic acid phosphatase (PAP), and in 1992, subjects were examined by DRE, transrectal sonography (TRUS) and PSA using an E-test TOSOH II Kit.1) The cut off value was determined between non-cancer subjects and prostate cancer patients. When the cut off value was 5.5ng/ml, the sensitivity, specificity and accuracy as a prostate marker were 73.9%, 95.3%, and 94.6%, respectively.2) The relationship between serum PSA coscentration, prostate size estimated by TRUS and age was investigated. The serum PSA was directly correlated with patient age and prostatic volume. The serum PSA concentration increased by 0.04ng/ml/year.3) The PPV (positive predictive value) of PSA (26.1%) is better than that for DRE (7.4%) or TRUS (8.1%). Thr sensitivity of PSA, DRE and TRUS is 73.9%, 49.6% and 21. 4%, respectively