ASCO GU 2018: Impact of Decipher test on adjuvant and salvage treatments received following radical prostatectomy

San Francisco, CA (UroToday.com) Dr. John Gore form the University of Washington and colleagues presented their findings assessing the impact of the Decipher test on adjuvant and salvage radiation therapy among men undergoing radical prostatectomy. Indeed patients, their families, and providers have tremendous uncertainty as they decide on intervention with adjuvant or salvage radiation therapy after radical prostatectomy. As such, the objective of this study was to prospectively evaluate the impact of the Decipher test, a genomic classifier which predicts metastasis post-radical prostatectomy [1], on providers’ decision-making for adjuvant and salvage radiation therapy.

This study included 150 men considering adjuvant radiation therapy and 115 men considering salvage radiation therapy from 19 sites across the US. Participating providers submitted a management recommendation prior to processing the Decipher test and again after receiving test results. Patients were then followed for 12 months to assess actual treatment received, patient reported decisional conflict scale (DCS) scores, and a validated survey on prostate cancer-related anxiety.

For Pre-Decipher test, observation was recommended for 89% of adjuvant men and 58% of salvage men, however post-Decipher test, 17% of treatment recommendations changed in the adjuvant arm and 30% of recommendations changed in the salvage arm. Among men considering adjuvant radiation therapy, 78% maintained their recommended management 12 months after the Decipher test, comparable to 76% of men considering salvage radiation therapy maintaining their recommended treatment after testing. Among 21 adjuvant radiation therapy men who intensified their treatment (observation to adjuvant radiation therapy or adjuvant radiation therapy to adjuvant radiation therapy plus androgen deprivation therapy), 5 (24%) experienced biochemical recurrence with a detectable PSA. In adjuvant radiation therapy men, prostate cancer-specific anxiety decreased differently among Decipher risk categories (p-value = 0.045), most notably among Decipher high risk men [9.07 (7.87, 10.26) pre-Decipher to 5.61 (5.35, 5.88) 12 months post-Decipher]. In salvage radiation therapy men, prostate cancer-specific anxiety decreased differently among those whose treatment were concordant [10.28 (8.1,12.47) pre-Decipher, 7.18 (6.82,7.54) 12 months post-Decipher] and those whose treatment was intensified (p-value = 0.01), and decreased differently among low-risk and high-risk Decipher patients (p = 0.04). As the authors note, the main limitation of the study is that patients were their own control in that there was no group unexposed to Decipher testing.

Dr. Gore concluded that use of the Decipher test changed treatment decisions that was consistent with the eventual treatment received in >75% of adjuvant and salvage radiation therapy men after radical prostatectomy. Importantly, from pre-Decipher visit to 12 months post-Decipher visit, patients in the adjuvant and salvage radiation therapy arms had decreased anxiety level. 

Reference: 
1. Klein EA, Haddad Z, Yousefi K, et al. Decipher Genomic Classifier Measured on Prostate Biopsy Predicts Metastasis Risk. Urology 2016;90:148-152.

Presented by: John Gore, University of Washington, Seattle, WA

Co-Authors: Marguerite Du Plessis, Darlene Dai, Kasra Yousefi, Darby Thompson, Lawrence Ivan Karsh, Brian R. Lane, Michael Franks, David Chen, Mark Bandyk, Adam S. Kibel, Hyung Lae Kim, William Thomas Lowrance, Paul Maroni, Scott David Perrapato, Edouard John Trabulsi, Robert J. Waterhouse, Elai Davicioni, Yair Lotan, Daniel W. Lin

Written By: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre at the 2018 American Society of Clinical Oncology Genitourinary (ASCO GU) Cancers Symposium, February 8-10, 2018 - San Francisco, CA