Recent Advances in Systematic and Targeted Prostate Biopsies

Abstract

Prostate biopsy is the definitive investigation to diagnose prostate cancer. The ideal procedure would be one that offers fast and efficient results safely as an outpatient procedure. Historically, transrectal ultrasound (TRUS) biopsy is considered the gold standard but transrectal biopsy can under-sample the anterior and apical regions of the prostate and is associated with a risk of prostate biopsy-related sepsis, which may require intensive care admission. Transperineal (TP) biopsy addresses the inefficient sampling of TRUS biopsy but historically has been done under general anaesthetic, which makes it difficult to incorporate into timed diagnostic pathways such as the National Health Service (NHS) 2-week cancer pathway. TRUS biopsy has remained the mainstay of clinical diagnosis because of its simplicity; however, the recent development of simpler local anaesthetic transperineal techniques has transformed outpatient biopsy practice. These techniques practically eliminate prostate biopsy-related sepsis, have a shallow learning curve and offer effective sampling of all areas of the prostate in an outpatient setting. The effectiveness of TP biopsy has been enhanced by the introduction of multiparametric MRI prior to biopsy, the use of PSA density for risk stratification in equivocal cases and combined with more efficient targeted and systematic biopsies techniques, such as the Ginsburg Protocol, has improved the tolerability and diagnostic yield of local anaesthetic TP biopsies, reducing the risk of complications from the oversampling associated with transperineal template mapping biopsies. Areas where the literature remains unclear is the optimum number of cores needed to detect clinically significant disease (CSD) in patients with a definable lesion on MRI, in particular, whether there is a need for systematic biopsy in the face of equivocal MRI findings to ensure no CSD is missed. The Covid-19 pandemic has had a profound impact on prostate cancer referrals and prostate biopsy techniques within the UK; prior to the pandemic 65% of all prostate biopsies were TRUS, since the pandemic the proportions have reversed such that now over 65% of all prostate biopsies in the NHS are transperineal.

Keywords: Covid-19; local anaesthetic; prostate biopsies; transperineal; transrectal.

Figure 1

Transperineal template biopsy with brachytherapy grid. Image courtesy from BXTA.

Figure 2

Ginsburg Protocol template. Adapted from Eur Urol, Hansen N, Patruno G, Wadhwa K, et al. Magnetic Resonance and Ultrasound Image Fusion supported transperineal prostate biopsy using the ginsburg protocol: technique, learning points, and biopsy results. 332–340, Copyright (2016), with permission from Elsevier.

Figure 3

PrecisionPoint. Image courtesy with permission from Perineologic (https://perineologic.com/precisionpoint/)

Figure 4

Percentage of TRUS biopsy vs TP biopsy by year 2014–2021 (R Popert, Guy's & St Thomas' Hospital, Personal Communication, June 2021).