Systematic transperineal ultrasound guided template biopsy of the prostate in patients at high risk

Abstract

Purpose: A negative biopsy result does not necessarily equate with cancer in specific high risk groups. We describe an alternative systematic biopsy technique for evaluating this subgroup of patients.

Materials and methods: From March 1997 to May 1999 a total of 88 men underwent systematic ultrasound guided biopsy using the transperineal template technique. All patients had undergone at least 1 and 75 (85%) had undergone 2 or more previous sets of biopsies. In addition, study inclusion required high risk parameters, including prostate specific antigen (PSA) velocity greater than 0.75 ng./ml., PSA greater than 10 ng./ml. or previous prostatic intraepithelial neoplasia on biopsy, and/or atypical small cell acinar proliferation.

Results: Cancer was identified in 38 of the 88 men (43%) in this high risk subgroup undergoing repeat biopsy. A mean of 15.1 previous biopsy cores had been obtained. The most common biopsy grade was 6 (range 4 to 9). Adenocarcinoma was identified in the transition zone area in 29 of 38 cases (76%), including 15 (39%) in which disease was detected in the transition zone only. Persistent PSA acceleration greater than 0.75 ng./ml. was the major indicator for transperineal template biopsy in 83 of the 88 patients (94%). The only significant independent variable predictive of positive biopsy was prostate volume. Mean prostate volume in the positive and negative biopsy groups was 48 and 73 gm., respectively (p <0.001). Complications were rare and self-limiting, consisting primarily of hematuria and urinary retention requiring overnight catheterization in 2 patients.

Conclusions: Systematic transperineal template biopsy of the prostate is a safe and precise repeat biopsy technique in patients who remain at high risk for adenocarcinoma.