Re-biopsy of the Prostate Using a Stereotactic Transperineal Technique

Abstract
In this study we investigated the detection rate and morbidity of stereotactic transperineal prostate re-biopsy with 3-dimensional mapping for diagnosis of nonpalpable isoechoic occult prostate malignancy. A total of 180 consecutive patients with continued increasing total prostate specific antigen and at least 1 prior benign transrectal prostate biopsy underwent stereotactic transperineal prostate biopsy at a single outpatient institution between April 2004 and March 2006. Similar to a prostate brachytherapy procedure, patients were placed in the dorsal lithotomy position. With the patient under general anesthesia, and using transrectal ultrasound, a perineal brachytherapy template and stabilizing device, the prostate was positioned on the implant grid. It was equally divided into 8 sections (octants) according to x and y coordinates on the mid gland axial image. The midplanes of axial and sagittal prostate gland images for each patient determined the x, y and z coordinates that would occupy each octant. Tissue cores were initially obtained from the apical octants, followed by identical x and y coordinates of the basilar octants. Specimens from each specific octant were placed in 1 of 8 specimen jars and pathological review was reported accordingly. Stereotactic transperineal prostate biopsy yielded positive biopsies identifying adenocarcinoma in 68 of 180 (38%) patients. Acute urinary retention developed in 18 of 180 (10%) patients requiring an indwelling urinary catheter upon discharge home. In all patients estimated blood loss was less than 5 cc and median pain score was 1 of 10. Stereotactic transperineal prostate biopsy is extremely well tolerated and useful for diagnosis of nonpalpable isoechoic occult prostate malignancy. Additionally, stereotactic transperineal prostate biopsy provides comprehensive tissue sampling with accurate 3-dimensional mapping of malignancy in this select group of patients.