No AccessJournal of UrologyAdult Urology1 Sep 2021

Optimizing Spatial Biopsy Sampling for the Detection of Prostate Cancer

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    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.

    Materials and Methods:

    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 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.


    A total of 16,459 total cores from 971 men were included in the study data sets, 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 and 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 RTB 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.


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    Funded by NIH NCI R21 CA220352, NIH NCI P50 CA092131, and a NVIDIA Corporation Academic Hardware Grant (CWA); NCI F30CA210329, NIH NIGMS GM08042, and the UCLA-Caltech Medical Scientist Training Program (KVS); and NIH NCI R01 CA195505 and R01 CA158627 (LSM).

    All data were used for this work under the approval of the UCLA Institutional Review Board (IRB Nos. 11-001580 and 16-001087) and in compliance with HIPAA regulations.

    None of the sponsors of this study were involved in study design or performance, or in the writing or submission of this manuscript.

    Financial interest and/or other relationship with Avenda Health (LSM, AMP) and the American Medical Association (KVS). No other authors have competing interests to disclose.