[Pathological basis for elevation of serum prostate specific antigen]

67 patients with serum prostate specific antigen (PSA) over 4ng/ml were investigated pathologically. All the patients had prostatic lesions: prostate cancer (24) and benign prostatic lesions (43). The serum PSA was conspicuously higher in the carcinoma group than in the benign group (P < 0.01). When 10ng/ml was used as the low limit to detect prostate cancer, the sensitivity and specificity were 83.3% and 74.4% respectively. We suggest that the range of serum PSA from 4.0 to 10.0ng/ml should be considered dangerous in detecting prostate cancer. The epithelium-blood barrier lesion and epithelial hyperplasia of the prostate might be the pathological basis for the elevation of serum PSA.