AUA 2018: Validation of the Decipher Biopsy Test to Predict Adverse Pathology in Men Diagnosed with Low and Favorable Intermediate Risk Prostate Cancer

San Francisco, CA (UroToday.com) The Decipher Biopsy (Bx) test has been validated to predict metastasis and prostate cancer specific mortality in men with intermediate and high-risk prostate cancer (PCa). In this study, the authors validated Decipher Bx for the prediction of high-grade or stage (HGS) PCa at radical prostatectomy (RP) in men with NCCN low and favorable-intermediate risk group PCa. 
A cohort of 207 men with NCCN low or favorable intermediate risk group PCa treated with RP at 6 community and academic practices who had complete tumor pathology and genomic information available were selected for analysis. Univariable (UVA) and multivariable (MVA) logistic regression were used to evaluate Decipher Bx scores (range: 0-1) and risk groups (low: 0.6) and CAPRA model. The primary endpoint was HGS defined as primary Gleason pattern 4 or greater, or pathologic stage T3b or greater or lymph node involvement (LNI). 

The median age of the cohort was 61 years, median PSA was 5.4 ng/mL, 81% were stage T1c, and 83% and 17% had Bx Grade group 1 or 2 disease. 72% and 28% were NCCN low and favorable-intermediate risk, respectively. CAPRA classified 73% as low (0-2) and 27% as average risk (3-5). Decipher Bx classified 79% as low, 15% as intermediate and 6% as high genomic risk. RP Grade group was 1 in 40.6%, 2 in 47.8% and 3-5 in 11.6%. Pathologic stage T3b or positive lymph nodes were observed in 7 men (3%), yielding 27 men (13%) with HGS PCa at RP.

Decipher Bx was an independent predictor of HGS with an odds ratio (OR) of 1.34 per 0.1-unit increase (p=0.014). On MVA, when modeled with CAPRA, Decipher Bx was the only significant predictor of HGS (OR 1.31 per 0.1-unit increase, p=0.039). Decipher Bx low risk group had negative predictive value (NPV) of 92% for the HGS endpoint. In exploratory analysis, a very low risk cut-point (<0.2) had a sensitivity of 96% and an NPV of 99%. Patients with Decipher Bx <0.2 made up 26.5% of the cohort.

The authors concluded that prediction of HGS PCa at RP among men with NCCN low and favorable-intermediate risk disease has high sensitivity and NPV. Ongoing studies aim to validate the very low risk genomic cut-point to guide decision-making and follow-up biopsy protocols for men considering or in active surveillance (AS). 


Presented by: Brian Lane, Grand Rapids, MI, USA
Co-Authors: Hyung Kim, MD, Cedars Sinai Medical Center, Ping Li, Los Angeles, CA, Huei­Chung Huang, Samineh Deheshi, Tara Marti, Vancouver, Canada, Beatrice Knudsen, Los Angeles, CA, Hatem Abou­Ouf, Calgary, Canada, Lucia Lam, Maria Aranes, Marguerite du Plessis, Elai Davicioni, Vancouver, Canada, Jeffrey Tosoian, Ashley Ross, Baltimore, MD, John Davis, Houston, TX, James Mohler, Buffalo, NY, M. Eric Hyndman, Calgary, Canada, Eric Klein, Cleveland, OH, Tarek Bismar, Calgary, Canada, Hyung Kim*, Los Angeles, CA

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA