Serum prostate-specific antigen values for the prediction of clinical stage and prognosis in patients with prostate cancer: an analysis of 749 cases.

Abstract

The clinical significance of pretreatment serum prostate-specific antigen (PSA) values was studied to determine the ability to predict clinical stage and prognosis using a relatively large number of patients with prostate cancer. Serum PSA values at diagnosis were analyzed from 749 patients with newly-diagnosed prostate cancer and registered in the Tokai Urological Cancer Registry. Correlations between the PSA value, the clinical stage and prognosis of the patients were evaluated. Serum PSA values at each stage of diagnosis showed positivity (> or = 3.6 ng/mL) in 23% (stage A1) to 91.2% (stage D2) of patients, and it was possible to obtain statistical differences between the stages, even between A1 and A2. Based on a cumulative study of PSA distribution, stages greater than A2 could be diagnosed using a cut-off of 7.2 ng/mL, with a 99.2% positive predictive value (PPV), and a 16.2% negative predictive value (NPV). At a PSA level of 10.8 ng/mL, stages greater than B2 could be predicted with a PPV of 95.3% but an NPV of 40.3%. Pretreatment PSA values were a significant prognostic indicator in stage D2 patients using 100 to 150 ng/mL as the cut-off values. These differences were primarily found in the poorly differentiated group, which showed a statistical difference using cut-off PSA values from 75 to 150 ng/mL. Serum PSA levels from a large number of patients can be used to predict the stage and prognosis of prostate cancer patients.