Volume adjustment for intermediate prostate-specific antigen values in a screening population.

Abstract

In a screening population of 812 men, between the ages of 55 and 77 years, and prostate-specific antigen (PSA) below 10.0 ng/ml (Hybritech), digital rectal examination (DRE) and transrectal ultrasonography of the prostate (TRUS) were performed. Seventeen prostate carcinomas were detected. Four methods of prostate volumetry were used to determine volume-adjusted PSA levels. These were PSA density for the total gland volume (PSAD), for the inner zone volume (PSAT) and population-specific excess PSA values. There was a significant difference between the benign and the malignant population for age, PSA, PSAD, PSAT and excess PSA values. The maximal discriminatory potential, analysed by the area under receiver ROC curve, was 0.90, reached for prolate spheroid determined excess PSA. For PSA alone this was 0.86. Volume-adjusted PSA values have no additional benefit beyond unadjusted values in screening for prostate carcinoma in this study.