Should Transition Zone Biopsies Be Added to 12-Core Systematic Biopsies of the Prostate?

Abstract

Purpose. To investigate the value of additional transition zone (TZ) biopsies following 12-core biopsies in the detection and staging of prostate cancer. Methods. From October 2006 to March 2007, 199 transrectal sonographic (TRUS)-guided prostate biopsies (group 1) in 12 peripheral zones (PZ) were performed. Another 199 consecutive patients (group 2) underwent two TZ biopsies in addition to twelve PZ biopsies from March 2007 to July 2007. Mean prostate-specific antigen (PSA) level, prostate volume, Gleason score, and cancer detection rate of each group were compared. The anatomic distribution of prostate cancer in group 2 was also analyzed. Results. Prostate cancer was detected in 76 of 199 patients (38.2%) in group 1 and 71 out of 199 patients (35.3%) in group 2. The cancer detection rate, mean PSA level, prostate volume, and Gleason score were not statistically different in the 2 groups. Cancer was detected by additional TZ biopsies alone in just one out of 71 patients (1.4%). Conclusion. Routine TZ biopsies following 12-core systematic biopsies are not warranted for the detection of TZ cancer because of their low additional yield.