Prostate Cancer Genomic Classifier Relates More Strongly to Gleason Grade Group Than Prostate Imaging Reporting and Data System Score in Multiparametric Prostate Magnetic Resonance Imaging-ultrasound Fusion Targeted Biopsies.

OBJECTIVE: To assess the association between Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) score, the Decipher score, and histologic grade of carcinoma in biopsy tissue among low- to intermediate-risk prostate cancer patients.
METHODS: MRI-ultrasound targeted biopsy of regions of interest and concurrent 12-core systematic biopsy was performed on men with Gleason grade group (GG) 1 and 2. We compared Decipher score with PI-RADS scores and biopsy Gleason GG. Subgroup analyses were performed to evaluate patients who underwent radical prostatectomy (RP), and men with Decipher testing from a targeted biopsy core.
RESULTS: One hundred two patients with GG1 and GG2 had biopsy Decipher testing. There was no significant difference in the median Decipher scores among the 3 multiparametric magnetic resonance imaging categories. Patients with GG2 vs GG1 in the setting of PI-RADS 4-5 had higher genomic scores (P = .01), but no significant difference was noted in patients with PI-RADS ≤3. The rate of genomic higher-risk disease on a targeted biopsy from PI-RADS5 was higher in GG2 (75%) vs GG1 (11.1%; P = .01). On multivariable logistic regression analysis, the Decipher score ≥0.45, (odds ratio (OR) 2.71; P = .02), and age (OR 1.11; P = .004) remained significant factors associated with Gleason GG2 on biopsy.
CONCLUSION: High-risk genomic classification can be seen across all combinations of PI-RADS categories and Gleason GG1 and GG2, confirming a potential utility for Decipher testing in men with low- to favorable intermediate-risk prostate cancer. The Decipher biopsy genomic test related to Gleason GG independent of PI-RADSv2 score. Confirmatory genomic testing for patients undergoing active surveillance appears more valuable than PI-RADSv2 score.