Incidence and pathological features of prostate cancer detected on transperineal template guided mapping biopsy after negative transrectal ultrasound guided biopsy.

ABSTRACT

PURPOSE: We determined the incidence of cancer detection by transperineal template guided mapping biopsy of the prostate in patients with at least 1 previously negative transrectal ultrasound guided biopsy. MATERIALS AND METHODS: From January 2005 to January 2012 at least 1 negative transrectal ultrasound guided biopsy was done in 485 patients in our clinical database before proceeding with transperineal template guided mapping biopsy. No study patient had a previous prostate cancer diagnosis. The incidence of patients with 1, 2, or 3 or greater previous transrectal ultrasound guided biopsies was 55.3%, 25.9% and 18.8%, respectively. Transperineal template guided mapping biopsy was done in 74.8% of patients for increasing or occasionally persistently increased prostate specific antigen, in 19.4% for atypical small acinar proliferation and in 5.8% for high grade prostatic intraepithelial neoplasia. RESULTS: For the entire study population a median of 59 cores was submitted at transperineal template guided mapping biopsy. Cancer was ultimately detected in 226 patients (46.6%) using the transperineal template guided method, including 196 (86.7%) with clinically significant disease according to the Epstein criteria. The most common cancer detection site on transperineal template guided mapping biopsy was the anterior apex. CONCLUSIONS: Transperineal template guided mapping biopsy detected clinically significant prostate cancer in a substantial proportion of patients with negative transrectal ultrasound guided biopsy. This technique should be strongly considered in the context of increasing prostate specific antigen with failed confirmation of the tissue diagnosis.