The Decipher® Prostate Test is a clinical-grade 22 mRNA-based test with a genomic classifier score that has been independently validated for predicting prostate cancer metastatic disease post radical prostatectomy. Patients with high GC scores have a significantly higher risk for metastasis than patients with low to average GC scores.
The utility of the Decipher biopsy test in multiparametric magnetic resonance imaging (mpMRI)-targeted biopsies in men with favorable-risk prostate cancer has not been evaluated. In this study, presented by Dr. Ghabili, the authors sought to assess the association between Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) score in mpMRI, the Decipher score, and the histologic grade of prostate cancer in biopsy tissue obtained from patients with low- to intermediate-risk disease.
The study occurred between 2015 and 2017 and included patients who underwent a mpMRI-ultrasound targeted biopsy of regions of interest and concurrent 12-core systematic biopsy. All patients were biopsy-naïve or with prior negative biopsy or on active surveillance for a Gleason grade group (GG) 1 or 2 disease on biopsy.
A total of 102 patients with GG1 (n=62) and GG2 (n=40) had Decipher testing performed on prostate biopsy-obtained tissue. There was a higher Decipher score in GG2 patients, as shown in figure 1. No difference was demonstrated in the Decipher scores across PIRADS categories within each grade group. Patients with GG2 vs. GG1 in the setting of PI-RADS 4 and 5 had higher genomic scores. Adverse pathology at radical prostatectomy found in GG2 with genomic higher-risk was demonstrated regardless of the PIRADS score (Figure 2).
Figure 1: Higher Decipher score in Gleason grade group 2
Figure 2: Adverse pathology at radical prostatectomy found in Gleason grade group 2 and genomic higher risk regardless of PIRADS score:
These results lead the authors to conclude that high-risk genomic classification can be seen across all combinations of PI-RADS categories and Gleason GG2. According to Dr. Ghabili, this confirmatory genomic testing for patients undergoing active surveillance appears more predictive than the PIRADS score.
Presented by: Kamyar Ghabili, MD, Department of Urology, Yale School of Medicine New Haven, CT, USA
Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at American Urological Association's 2019 Annual Meeting (AUA 2019), May 3 – 6, 2019 in Chicago, Illinois