Is There a Better Way to Biopsy the Prostate? Prospects for a Novel Transrectal Systematic Biopsy Approach

The study reported here was undertaken to investigate a novel method of systematic, 3-dimensional, template-guided, transrectal ultrasound-guided prostate biopsy. The TargetScan transrectal ultrasound and prostatic biopsy system (Envisioneering Medical Technologies, St. Louis, MO) uses a stationary transrectal ultrasound probe that acquires 3-dimensional and simultaneous biplanar ultrasound imaging. With the use of prostate-specific measurements, targeted transrectal biopsy specimens of the prostate are taken. The precise location of each specimen is defined by 2 coordinates: depth in centimeters proximal from the apex of the prostate, and degree of rotation (clockwise or counterclockwise from 12 o'clock). This device has been evaluated when used with radical prostatectomy specimens. Studies on 20 radical prostatectomy specimens disclosed that simulated TargetScan biopsy correctly identified cancer in 16 (80%) prostates and high-grade prostatic intraepithelial neoplasia in 2 others. Simulated TargetScan biopsy correctly characterized 88% of prostatic octants in terms of whether or not they harbored cancer. This technique was reproducible from operator to operator, and 85% biopsy core concordance was attained when the TargetScan protocol was simulated in 2 urology residents. The TargetScan biopsy system seems to be an effective transrectal alternative to transperineal, 3-dimensional, ultrasound-guided biopsies. Its reproducibility from operator to operator suggests that it may be useful for guiding rebiopsy of specific locations within the prostate and for providing targeted focal prostate cancer therapy.