Optimizing Spatial Biopsy Sampling for the Detection of Prostate Cancer.

The appropriate number of systematic biopsy cores to retrieve during Magnetic Resonance Imaging (MRI)-targeted prostate biopsy is not well defined. We aimed to demonstrate a biopsy sampling approach that reduces required core count while maintaining diagnostic performance.

We collected data from a cohort of 971 men who underwent MRI-ultrasound fusion targeted biopsy for suspected prostate cancer. A regional targeted biopsy (RTB) was evaluated retrospectively; only cores within 2 cm of the margin of a radiologist-defined region of interest (ROI) were considered part of the RTB. We compared detection rates for clinically significant prostate cancer (csPCa) and cancer upgrading rate on final whole mount pathology after prostatectomy between RTB, combined, MRI-targeted, and systematic biopsy.

16,459 total cores from 971 men were included in the study datasets, of which 1,535 (9%) contained csPCa. The csPCa detection rates for systematic, MRI-targeted, combined, and RTB were 27.0% (262/971), 38.3% (372/971), 44.8% (435/971) and 44.0% (427/971) respectively. Combined biopsy detected significantly more csPCa than systematic and MRI-targeted biopsy (p <0.001, p=0.004 respectively), but was similar to RTB (p=0.71), which used on average 3.8 (22%) fewer cores per patient. In 102 patients who underwent prostatectomy, there was no significant difference in upgrading rates between RTB and combined biopsy (p=0.84).

A regional targeted biopsy approach can maintain state-of-the-art detection rates while requiring fewer retrieved cores. This result informs decision-making about biopsy site selection and total retrieved core count.

The Journal of urology. 2021 Apr 28 [Epub ahead of print]

Alex G Raman, Karthik V Sarma, Steven S Raman, Alan M Priester, Sohrab Afshari Mirak, Hannah H Riskin-Jones, Nikhil Dhinagar, William Speier, Ely Felker, Anthony E Sisk, David Lu, Adam Kinnaird, Robert E Reiter, Leonard S Marks, Corey W Arnold

Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, California., Department of Urology, David Geffen School of Medicine, University of California, Los Angeles, California., Department of Pathology & Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, California.