Genomic prostate score and treatment selection in favourable intermediate-risk prostate cancer.

Objective: To assess the factors associated with the use of active surveillance (AS) in NCCN favourable intermediate-risk (FIR) prostate cancer (PCa) patients who received the 17-gene Genomic Prostate Score (GPS) assay. Material and Methods: Contemporary data were collected from academic and large community group practices across the United States. Eligible patients had localized PCa classified as FIR per NCCN guidelines and received a GPS report between May 2017 and April 2019. Higher GPS results (scale: 0-100) were associated with a higher risk of adverse outcomes. The proportion of patients selecting AS was calculated with 95% confidence intervals. Uni-and multivariable logistic regression analyses were performed to determine the association between AS selection and relevant covariates. Results: There were 324 eligible patients (Gleason Score 3 + 4, 79%; PSA 10-20 ng/ml, 19%; clinical stage T2b-T2c, 2%; median percent positive cores, 16.7%; median GPS result, 26). The distribution of GPS results was 0-19 (23%), 20-40 (60%), and 41-100 (16%). Overall, 31% (95% CI 26%, 36%) selected AS: 58% (46%, 69%) with GPS 0-19, 27% (21%, 33%) with GPS 20-40, and 6% (1%, 16%) with GPS 41-100. In univariable models, the Gleason score, percent positive cores, PSA, and GPS results were significantly associated with AS selection. In a multivariable model, the percent positive cores and the GPS result remained significantly associated with AS selection. AS persistence was 91% (82%, 95%) at 12 months. Conclusions: The GPS result and percent positive cores appear associated with AS use after controlling for relevant clinical variables in NCCN FIR prostate cancer patients.