Prostate biopsy after ano-rectal resection: value of CT-guided trans-gluteal biopsy

We describe our single-institutional experience with computed tomography (CT)-guided percutaneous transgluteal biopsy of the prostate in patients in whom transrectal ultrasound-guided biopsy is precluded by prior ano-rectal resection. Between March 1995 and April 2007, 22 patients had 34 prostate biopsies (mean age 68; mean PSA 29 ng/ml; mean follow-up 6.1 years). The charts of patients who had transgluteal biopsy were reviewed for demographic, complications and pathology. Ninety-five percent (21/22) of primary biopsies were diagnostic. Of the 21 diagnostic biopsies, 11 were positive for prostate cancer and ten were definitive benign samples. Seventy-three percent (8/11) of the patients had progressive PSA elevation that mandated 11 further prostate biopsies. Six patients had a second biopsy, one patient had a third and one patient had a fourth biopsy. Among patients who had serial biopsies, 38% (3/8) had prostate cancer. No complications or death occurred. A malignant biopsy was not significantly associated with core number (P = 0.58) or a high PSA level (P = 0.15). CT-guided transgluteal biopsy of the prostate is safe and effective.