Top Line: Does the Decipher genomic classifier (GC) more accurately predict which patients with high risk prostate cancer are at risk of adverse outcomes?
The Study: In this study, biopsy specimens from 3 RTOG trials of definitive radiation for high risk prostate cancer (9202, 9413, and 9902) were pooled. Of 3197 patients in these trials, just 265 (8%) had tissue available that was sufficient for testing and that passed GC quality control. Of those, 20% were Black, 40% had T3-4 disease, and 45% had grade group 4-5 disease. An interesting side note is that the age of the biopsy specimens from these trials (15-30 years old) depresses the GC scores relative to the standard commercial cut points for risk. So, the authors had to adjust scores so that instead of 63% of patients having a low risk GC only 30% did, which is more comparable to the spectrum of high risk prostate cancer. With that, 28% had a low risk GC, 16% had intermediate risk, and 57% had high risk. On multivariable analysis, GC score was prognostic of overall survival, prostate cancer mortality, and distant metastasis. The 10 year risk of DM was 6% for low GC, 15% for intermediate GC, and 26% for high GC. Overall survival at 10 years was 65% for low GC, 58% for intermediate GC, and 49% for high GC. While this provides strong evidence of the prognostic value of the GC in high risk disease, what we’re really looking forward to are the results of trials like PREDICT-RT that use the GC to inform treatment decisions.
TBL: The Decipher GC performed on pre-treatment biopsy specimens is prognostic of DM risk and survival in men receiving radiation for high risk prostate cancer.
- Nguyen, Int J Radiat Oncol Biol Phys 2022