Multi-institutional evaluation of multiparametric MRI and fusion-guided prostate biopsy in a biopsy-naive population.

Abstract

60 Background: Multiparametric MRI (mpMRI) and fusion biopsy (FB) has proven beneficial in men with a prior negative systematic biopsy (SB) or diagnosis of prostate cancer (CaP). The aim of the study was to evaluate mpMRI and FB in a biopsy-naive population. Methods: A multi-institutional review was performed on patients with no prior biopsy history who underwent mpMRI followed by concurrent FB and SB. Imaging protocol was standardized across institutions. Gleason score (GS) distribution/risk classifications were recorded. Univariate analysis was performed to compare FB versus SB. Results: A total of 361 biopsy-naive men were identified from 4 institutions. GS distribution/risk classification for FB and SB are presented in the table. Overall cancer detection rate (CDR) was 65.4%. In biopsy-naive men, FB detected a greater absolute number of high grade disease with 13% more high risk CaP than SB (78 vs 69). Additionally, FB detected 21% fewer cases of GS 6 CaP (57 vs 69). The CDR for FB alone was 57.3% with only 3 intermediate-risk and 1 high-risk patient not identified. The addition of SB to FB resulted in diagnosing 25 added cases of low-risk disease for each high risk CaP detected. The CDR of SB alone was 59.6%, however, 2 intermediate- and 4 high-risk CaP were missed. The addition of FB to SB alone resulted in only 4 added cases of low-risk CaP for each high-risk CaP detected. Conclusions: In biopsy-naive men, mpMRI and fusion biopsy detects a greater number of patients with high-risk disease while decreasing the detection of low-risk CaP. Additional studies with greater power will be required to validate the potential benefit of mpMRI and FB in patients with no prior biopsy history. [Table: see text]