Are transition zone biopsies still necessary to improve prostate cancer detection? Results from the tyrol screening project.

OBJECTIVES: The present retrospective study was designed to investigate the value of transition zone (TZ) biopsies for prostate cancer (PC) detection rate in a combined contrast enhanced color Doppler targeted (CECD) and gray-scale systematic biopsy (SB) approach.
METHODS: PSA screening participants totalling 1475 with tPSA of >1.25 ng/ml (fPSA< or =18%) were assessed. Ten SB and additionally 5 or fewer CECD were performed. The impact of TZ biopsies on the PC detection rate and the biological significance of the detected TZ-cancers were analyzed.
RESULTS: Out of 1475 biopsied patients, 395 (26.8%) were identified as PC patients; 5925 biopsy cores from these patients were analyzed. In 86 patients (21.8% of PC), we found 102 PC- positive cores in the TZ, and only in 9 of them solitary TZ-cancers without any other PC-location (2.3% of PC or 0.6% of all investigated patients). Pathologic findings after retropubic prostatectomy (RPE) revealed multifocal adenocarcinoma including involved peripheral zone (PZ) in eight of these nine patients, and solitary TZ-cancer in one patient. There was no positive correlation between prostate volume and TZ-detection rate and no patient with solitary TZ-PC after rebiopsy.
CONCLUSION: Biopsy revealed 9 solitary TZ cancers (1.8%) and RPE revealed only one of them to be truly TZ-confined cancer (0.6%). Furthermore PC-detection did not improve, even in patients with rebiopsy, and there was no correlation between detection of TZ-cancers and prostate volume. A combined use of CECD and SB to investigate participants of a PSA-screening program suggests that TZ-biopsies do not improve PC detection rate and are therefore unnecessary.