pT3 Predictive Factors in Patients with a Gleason Score of 6 in Prostate Biopsies

PURPOSE Often, a diagnosis of pT3 is made on the basis of radical retropubic prostatectomy specimens, despite a Gleason score of 6 on the preoperative prostate biopsy. Thus, we investigated the preoperative variables in patients displaying these characteristics. MATERIALS AND METHODS Study subjects comprised patients at our institute from 1996 to July 2010 who had exhibited a Gleason score of 6 on their prostate biopsies and had undergone a radical retropubic prostatectomy. Through univariate and multivariate analysis, we investigated pT3 predictive factors including age, preoperative prostate-specific antigen (PSA) levels, transrectal ultrasonography (TRUS)-weighted prostate volume, digital rectal examination findings, bilaterality via prostate biopsy, prostatic cancer in prostate base cores via prostate biopsy, maximum length and percent of prostatic cancer, and number of cores detected in prostatic cancer via prostate biopsy. RESULTS In the univariate logistic regression mode, a PSA value of 7.4 ng/ml or higher, TRUS-weighted PSA density of 0.2 ng/ml/cc or higher, prostate cancer detected in the basal core, and prostate cancer detected in 2 or more cores out of 12 were predictive factors for extraprostatic extension. Independent predictive factors for stage pT3 were a PSA of 7.4 ng/ml or higher and prostate cancer detected in 2 or more cores out of 12. CONCLUSIONS In the case of patients with the foregoing risk factors, it is advisable not to perform nerve-sparing surgery but to prepare for the possibility of a pT3 stage.