The 17-Gene Genomic Prostate Score Test as a Predictor of Outcomes in Men with Unfavorable Intermediate Risk Prostate Cancer

Objectives: To evaluate the association of the Genomic Prostate Score (GPS) assay result with biochemical recurrence (BCR), distant metastases (DM), and prostate-specific death (PCD) in unfavorable intermediate (UFI) risk prostate cancer patients. The GPS assay is used to help guide management decisions for newly diagnosed low and favorable intermediate (FI) risk disease. Methods: GPS results from 2 studies (Center for Prostate Disease Research [CPDR]; Kaiser Permanente Northern California [KPNC]) in men treated with radical prostatectomy were analyzed to determine associations of the GPS result with BCR, DM, and PCD in UFI risk disease. Analyses included 299 intermediate risk prostate patients, 175 of whom had UFI risk disease (KPNC = 103; CPDR = 72). Results: The GPS result as a dichotomous value (≤40 vs >40) was a significant predictor of BCR in UFI patients in multivariate analyses (hazard ratio [HR] 6.0; 95% confidence interval [CI] 2.0-22.4; P = .0035; CPDR). The GPS result was a strong predictor of all 3 endpoints in multivariate analyses (BCR HR 7.1; 95% CI 5.7-8.8; P < .0001; DM HR 5.4; 95% CI 3.8-7.8; P < .0001; PCD HR 3.4; 95% CI 1.5-8.9; P = .006; KPNC). UFI patients with GPS >40 had outcomes consistent with high-risk disease, whereas UFI patients with GPS ≤40 had outcomes similar to FI risk patients (CPDR/KPNC). Conclusions: The GPS result was a strong independent predictor of BCR, DM, and PCD in intermediate risk prostate cancer. UFI patients with GPS >40 have a poor prognosis and may benefit from additional therapeutic options.