Prospective study to define the clinical utility and benefit of Decipher testing in men following prostatectomy.

Genomic classifiers (GC) have been shown to improve risk stratification post prostatectomy. However, their clinical benefit has not been prospectively demonstrated. We sought to determine the impact of GC testing on postoperative management in men with prostate cancer post prostatectomy.

Two prospective registries of prostate cancer patients treated between 2014 and 2019 were included. All men underwent Decipher tumor testing for adverse features post prostatectomy (Decipher Biosciences, San Diego, CA). The clinical utility cohort, which measured the change in treatment decision-making, captured pre- and postgenomic treatment recommendations from urologists across diverse practice settings (n = 3455). The clinical benefit cohort, which examined the difference in outcome, was from a single academic institution whose tumor board predefined "best practices" based on GC results (n = 135).

In the clinical utility cohort, providers' recommendations pregenomic testing were primarily observation (69%). GC testing changed recommendations for 39% of patients, translating to a number needed to test of 3 to change one treatment decision. In the clinical benefit cohort, 61% of patients had genomic high-risk tumors; those who received the recommended adjuvant radiation therapy (ART) had 2-year PSA recurrence of 3 vs. 25% for those who did not (HR 0.1 [95% CI 0.0-0.6], p = 0.013). For the genomic low/intermediate-risk patients, 93% followed recommendations for observation, with similar 2-year PSA recurrence rates compared with those who received ART (p = 0.93).

The use of GC substantially altered treatment decision-making, with a number needed to test of only 3. Implementing best practices to routinely recommend ART for genomic-high patients led to larger than expected improvements in early biochemical endpoints, without jeopardizing outcomes for genomic-low/intermediate-risk patients.

Prostate cancer and prostatic diseases. 2019 Nov 12 [Epub ahead of print]

Joseph Marascio, Daniel E Spratt, Jingbin Zhang, Edouard J Trabulsi, Tiffany Le, Worlanyo Sosu Sedzorme, Whitney H Beeler, Elai Davicioni, Bashar Dabbas, Daniel W Lin, John L Gore, Matthew Bloom, Mark Mann, J Ryan Mark, Anne Calvaresi, James L Godwin, Peter McCue, Mark D Hurwitz, W Kevin Kelly, Costas D Lallas, Karen E Knudsen, Leonard G Gomella, Adam P Dicker, Robert B Den

Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, PA, USA., Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, USA., Decipher Biosciences, San Diego, CA, USA., Department of Urology, Thomas Jefferson University Hospital, Philadelphia, PA, USA., Department of Urology, University of Washington, Seattle, WA, USA., Department of Medical Oncology, Thomas Jefferson University Hospital, Philadelphia, PA, USA., Department of Pathology, Thomas Jefferson University Hospital, Philadelphia, PA, USA., Sidney Kimmel Cancer Center, Philadelphia, PA, USA., Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, PA, USA. .