Anterior sampling may be safe alternative for prostate biopsy

April 23, 2013

Transrectal anterior zone sampling of the prostate may be a viable alternative to transperineal template biopsies in patients with negative previous biopsies and with rising PSA or persistently elevated PSA, researchers from the United Kingdom report.

Milan, Italy-Transrectal anterior zone sampling of the prostate may be a viable alternative to transperineal template biopsies in patients with negative previous biopsies and with rising PSA or persistently elevated PSA, researchers from the United Kingdom report.

In a poster presentation at the European Association of Urology annual congress in Milan, Italy, first author Amol Pandit, MD, discussed the advantages of taking targeted anterior zone biopsies in addition to standard lateral lobe biopsies in patients undergoing re-biopsy.

“Transrectal targeting of the anterior zone with two to four additional cores is a simple, safe, and cost-effective procedure. It is a good way of identifying a tumor that might otherwise go undetected. In a review of our radical prostatectomy data, we observed that a significant proportion of men with prostate cancer had anterior zone tumors at the time of radical prostatectomy. We consequently modified our technique in those patients undergoing repeat biopsies to include both anterior zone and lateral lobe cores, including the lateral point.

“We suggest that this may offer an alternative to transperineal template biopsy of the prostate,” said Dr. Pandit, senior clinical tutor at Abertawe Bro Morgannwg University Health Board Morriston Hospital, Swansea, United Kingdom.

The study included 23 patients, aged 53 to 79 years (median age, 64 years) with at least one negative previous biopsy (13 patients had one previous biopsy, nine patients had two, and one patient had more than two), and a rising PSA or persistently elevated PSA of 7.7 ng/mL to 42.5 ng/mL (median PSA, 20.9 ng/mL). Dr. Pandit obtained prostate biopsies through a standard transrectal ultrasound (TRUS)-guided approach. He obtained two to four cores from the anterior zone in addition to six to eight laterally placed cores from each of the lateral lobes, specifically targeting those areas that were not targeted earlier.

The biopsies were taken under local anesthesia between January 2012 to August 2012, using the Toshiba Aplio XG with a 6-MHz sector probe (Toshiba Medical Systems Europe, Zoetermeer, the Netherlands), using a spring-loaded 18-gauge needle and a Bard biopsy gun (Bard Medical Division, Covington, GA). Oral antibiotics were started 1 day prior to the biopsy procedure.

 

52.2% detection rate for anterior zone

The overall prostate cancer detection rate was 65.2% (15/23 patients) from both the anterior and lateral samples. Cancer detection from the anterior zone alone was 52.2% (12/23 patients). The cancers were stages T2A-T3, with T2B the most common stage. The fact that 52% of these were in the anterior zone underlines the importance of targeted anterior zone sampling, Dr. Pandit maintained.

Urologists attending Dr. Pandit’s presentation argued that it was not surprising to achieve a 65% cancer detection rate in patients with such high PSA values. To be able to compare a transperineal set of biopsies, a study should ideally include a much lower risk population, in which one would unlikely be able to show the same results, they argued. Furthermore, some physicians believed the small patient number reduced confidence in the results, while others believed that subjecting patients to fluoroquinolone antibiotics sets them up for transfecal-resistant strains, which is an unnecessary risk.

Dr. Pandit explained that when adopting a new technique or procedure, one looks for safety, efficacy, patient tolerability, and cost-effectiveness, especially in today’s harsh economic climate. This procedure fulfills all of those criteria, he said. It was well tolerated by patients and presented no further complications. He noted that prostate cancer detection rates with this technique were comparable to all other modalities, including transperineal template biopsies, but without the additional morbidity.UT