Abstract
Records of prostate cancer cases from participating SEER program registries, diagnosed during the period from 2010 through 2018, were linked to records of testing with the Decipher 22-gene genomic classifier (GC) prognostic test. Multivariable analysis was used to quantify the association between GC scores or risk groups and use of definitive local therapy after diagnosis in the GC biopsy tested cohort, and post-operative radiotherapy in the GC tested cohort as well as adverse pathology after prostatectomy.A total of 572,545 patients were included in the analysis, of which 8,927 patients underwent GC testing. GC biopsy tested patients were more likely to undergo active surveillance/watchful waiting (AS/WW) compared to untested patients (OR [95% CI] 2.21 [2.04 to 2.38], p < 0.001). AS/WW was highest for those with GC low risk classification (41%) as compared to those with intermediate (27%) or high (11%) GC risk (p < 0.001). Among NCCN low- and favorable-intermediate patients, higher GC risk was associated with greater use of local therapy (OR 4.79 [3.51 to 6.55], p < 0.001). Within this subset of patients who were subsequently treated with prostatectomy, high GC risk was associated with harboring adverse pathology (OR 2.94 [1.38 to 6.27], p = 0.005). Use of radiation after prostatectomy was significantly associated with higher GC risk group (OR 2.69 [1.89 - 3.84]).There is a strong association between use of the biopsy GC test and likelihood of conservative management. Higher genomic classifier scores are associated with higher rates of adverse pathology at time of surgery and greater use of post-operative radiotherapy. PATIENT SUMMARYThis study linked the use of the Decipher Genomic Classifier (GC) to a US national database of men with prostate cancer. Use of GC was associated with conservative management (ie, active surveillance). Among men who had high-risk GC scores and then had surgery, there was a three-fold higher chance of having worrisome findings in surgical specimens.
