Preliminary evaluation of measurement of serum prostate-specific antigen level in detection of prostate cancer.

The measurement was evaluated of serum prostate specific antigen (PSA) and prostatic acid phosphatase (PAP) levels for early detection of prostate cancer on a potentially high-risk group. A PSA level at 5.0 ng per ml and PAP at 4.0 ng per ml were chosen as the cut-off levels. Results obtained for PSA and PAP can be divided into three groups: Group I, with normal levels of PSA and PAP; Group II, with elevated PSA but normal PAP level; and Group III, with elevated levels of both PSA and PAP. Forty-five of 46 patients in Group I were diagnosed as normal, while 70 out of 99 patients in Group II were categorized as having prostatic carcinoma with stages ranging from A1 to D, and nine of nine patients in Group III had stage D carcinoma. Our results also indicated that the measurement of PSA had a greater sensitivity than that of PAP and that PSA measurement could be a valuable adjunct to the diagnosis of prostate cancer.