Abstracts from the Abstracts from the Mid-Atlantic Section of the AUA 2021

MA-AUA 2021 Abstracts Moderated Poster Session 1: Prostate Cancer Comparing MRI/US Fusion to Standard Prostate Biopsy in Determining Grade Reclassification at Confirmatory Biopsy in a Multi-Institutional Active Surveillance Cohort: A Pennsylvania Urology Regional Collaborative (PURC) Analysis D. Strauss 1 , R. Reddy 1 , M. Loecher 1 , K. Syed 2 , J. Danella 3 , S. Ginzburg 4 , L. Belkoff 5 , J. Tomaszewski 6 , E. Trabulsi 7 , E. Singer 8 , B. Jacobs 9 , J. Raman 10 , T. Guzzo 11 , R. Uzzo 12 , A. Reese 1 1 Temple University Hospital, Department of Urology, Philadelphia, PA, USA; 2 Healthcare Improvement Foundation, Philadelphia, PA, USA; 3 Geisinger Health System, Danville, PA, USA; 4 Einstein Healthcare Network, Philadelphia, PA, USA; 5 Midlantic Urology/Mainline Health, Bala Cynwyd, PA, USA; 6 Cooper University Health Care, Camden, NJ, USA; 7 Thomas Jefferson University, Philadelphia, PA, USA; 8 Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA; 9 University of Pittsburgh, Pittsburgh, PA, USA; 10 Penn State Milton S. Hershey Medical Center, Hershey, PA, USA; 11 University of Pennsylvania, Philadelphia, PA, USA; 12 Fox Chase Cancer Center, Philadelphia, PA, USA Introduction and Objective: Active surveillance (AS) has emerged as the optimal management of low-risk prostate cancer (CaP) patients, relying on an accurate confirmatory biopsy to stratify disease risk. Conflicting literature exists regarding whether multiparametric (mp) MRI/fusion biopsy improves detection of clinically significant cancers compared to standard 12-core trans rectal ultrasound (TRUS) at time of confirmatory AS biopsy. We aimed to analyze a prospectively maintained multi-institutional AS database to compare clinically significant reclassification rates between biopsy groups at confirmatory biopsy. Methods: The Pennsylvania Urological Regional Collaborative (PURC) database, a prospectively maintained consortium CaP database, was retrospectively queried for all low-risk CaP men on AS. Patients were categorized bymodality of confirmatory biopsy (either standard 12 core TRUS prostate biopsy or mpMRI targeted/ultrasound fusion prostate biopsy). The primary outcome of interest was grade group reclassification at the time of confirmatory biopsy. Results: The study cohort included 469 low risk men on AS, with 339 (72%) undergoing standard 12-core TRUS confirmatory biopsy and 130 (28%) undergoing fusion confirmatory biopsy. There were no differences between groups at index biopsy, regarding demographic or disease characteristics. (Table 1) Clinically significant grade reclassification, defined as GG2 or greater, was seen on 42% (54) of mpMRI biopsies vs. only 22% (74) of standard biopsies (p < 0.001). (Table 2) Conclusions: The use of mp-MRI for AS confirmatory biopsy, compared to standard 12-core TRUS biopsy, improved the detection of clinically significant cancer. These findings suggest the value of MRI/US fusion biopsy to appropriately identify higher risk men on AS who may benefit from definitive treatment. MP1-06 7