CLINICAL-SIGNIFICANCE OF PROSTATE-SPECIFIC ANTIGEN FOR EARLY-STAGE PROSTATE-CANCER DETECTION

The characteristics of serum prostate specific antigen (PSA) in normal Japanese men were studied in 1480 subjects examined by mass screening (MS) for prostate cancer (Pca) in Gunma Prefecture in 1992. The serum PSA concentration was correlated with patient age. The average serum PSA level increased by 0.04 ng/ml/year. The upper normal limits (95 pe rcentiles) of age specific PSA for normal men are 1.33 ng/ml for those aged 39-49 years, 3.65 ng/ml for those aged 50-59 years, 4.06 ng/ml f or those aged 60-69 years, 5.09 ng/ml for those aged 70-79 years and 5 .66 ng/ml for those aged 80-89 years. Among 227 normal men examined by our MS in 1991 and 1999, the PSA velocity (PSAV) was calculated to be 0.05 ng/ml/year. Among 10 Pca patients with normal PSA levels (< 6 ng /ml) detected previously by our MS, three had an abnormal PSAV. We dem onstrated the possibility that PSA density could distinguish between P ca and benign prostate hypertrophy. The significance of PSA as a Pca s creening modality should be evaluated across multiple age ranges and i n combination with previous PSA data and/or prostate volume estimated by sonography.