Early detection of prostate cancer in men with prostatism and intermediate prostate-specific antigen levels

Objectives. To determine the prevalence of prostate cancer and the diagnostic ability of prostate-specific antigen density (PSAD) in men with lower urinary tract symptoms and intermediate prostate-specific antigen (PSA) levels of 4 to 10 ng/mL (Hybritech assay) and to assess the clinical significance of prostate cancers in men who subsequently underwent radical prostatectomy. Methods. Six systematic transrectal ultrasonography (TRUS)-guided biopsies were performed in 153 symptomatic men (mean age, 66 years) with PSA levels between 4 and 10 ng/mL, irrespective of digital rectal examination (DRE) findings. Prostate volume was also determined by TRUS and PSAD was calculated (serum PSA divided by volume of entire prostate). The rate of positive biopsies was compared with PSAD (more than 0.2 versus less than 0.2), DRE (positive versus negative), and patient's age (more than 70 years versus 61 to 70 versus 60 or less). Eligible patients with cancer underwent radical prostatectomy, and specimens were analyzed with regard to clinical significance of tumors. Results. The overall cancer detection rate was 29.4%, PSAD and DRE, but not age, were both statistically significant in differentiating negative from positive biopsies. Independent of DRE findings, mean PSAD was significantly lower in biopsy-negative cases (0.29 +/- 0.17 and 0.25 +/- 0.16) than it was in positive cases (0.34 +/- 0.17 and 0.35 +/- 0.15). Half of the patients who underwent radical prostatectomy had pathologically non-organ-confined disease (more than pT3), 34% had positive margins, and 47% had a Gleason score of 8 to 10. PSAD, DRE, and age could not predict outcome, probably owing to the small number of patients. However, the number of positive biopsies (1 or 2 Versus 3 to 6) was able to predict pathologic stage. Conclusions. In men with lower urinary tract symptoms and intermediate PSA levels of 4 to 10 ng/mL, PSAD may be useful in the selection of patients for prostate biopsy. Carcinomas found using these criteria are of clinical importance.