The Role of Systematic and Targeted Biopsies in Light of Overlap on Magnetic Resonance Imaging Ultrasound Fusion Biopsy

Abstract

Background: The value of a systematic biopsy in men with magnetic resonance imaging (MRI)-visible regions of interest (ROIs) undergoing fusion biopsy (FBx) is unclear.

Objective: To determine the utility of concurrent systematic biopsy with ROI biopsy in detecting clinically significant prostate cancer (CSPC).

Design, setting, and participants: Retrospective study of 240 men who underwent FBx with the Artemis platform. Software captured biopsy distribution maps. Biopsy distribution maps were reviewed to determine which systematic cores overlapped with the ROI. Histopathology for overlapping systematic cores were reclassified as ROI cores.

Outcome measurements and statistical analysis: Detection of CSPC on true systematic biopsy was the outcome measured. Multivariable logistic regression was used to determine if age, prostate-specific antigen, prostate volume, prior biopsy status, and Prostate Imaging-Reporting and Data System categorization were associated with CSPC detection and Gleason grade upgrading on systematic biopsy.

Results and limitations: The median number of systematic cores overlapping with ROIs was 2 (interquartile range 1-2). After accounting for overlap, 14 men (5.8%) had a higher Gleason grade on systematic biopsy. Of these, seven (2.9%) were upgraded from benign and three (1.3%) from clinically insignificant cancer on systematic biopsy. In adjusted analysis, prior negative biopsy (odds ratio [OR] 0.46, 95% confidence interval [CI] 0.21-0.99; p=0.046) was associated with absence of CSPC on systematic biopsy, while age (OR 1.11, 95% CI 1.02-1.21; p=0.015) was associated with upgrading. Limitations include the retrospective data and the use of a single biopsy platform.

Conclusions: Detection of CSPC on systematic biopsy that might influence clinical decision-making is uncommon in men undergoing FBx. In men with a prior negative biopsy, a target-only FBx strategy could be considered because of the low yield on systematic biopsy.

Patient summary: We found that random prostate sampling adds little diagnostic value in men who are undergoing a targeted biopsy of suspicious lesions found on imaging, especially for men who have had a prior negative biopsy.

Keywords: Fusion biopsy; Magnetic resonance imaging; Prostate cancer.