Publication Abstract

Authors: Muralidhar V, Chen MH, Reznor G, Moran BJ, Braccioforte MH, Beard CJ, Feng FY, Hoffman KE, Choueiri TK, Martin NE, Sweeney CJ, Trinh QD, Nguyen PL

Title: Definition and Validation of "Favorable High-Risk Prostate Cancer": Implications for Personalizing Treatment of Radiation-Managed Patients.

Journal: Int J Radiat Oncol Biol Phys 93(4):828-35

Date: 2015 Nov 15

Abstract: PURPOSE: To define and validate a classification of favorable high-risk prostate cancer that could be used to personalize therapy, given that consensus guidelines recommend similar treatments for all radiation-managed patients with high-risk disease. METHODS AND MATERIALS: We studied 3618 patients with cT1-T3aN0M0 high-risk or unfavorable intermediate-risk prostate adenocarcinoma treated with radiation at a single institution between 1997 and 2013. Favorable high-risk was defined as T1c disease with either Gleason 4 + 4 = 8 and prostate-specific antigen <10 ng/mL or Gleason 6 and prostate-specific antigen >20 ng/mL. Competing risks regression was used to determine differences in the risk of prostate cancer-specific mortality (PCSM) after controlling for baseline factors and treatment. Our results were validated in a cohort of 13,275 patients using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. RESULTS: Patients with favorable high-risk disease had significantly better PCSM than other men with high-risk disease (adjusted hazard ratio [AHR] 0.42, 95% confidence interval [CI] 0.18-0.996, P=.049) and similar PCSM as men with unfavorable intermediate-risk disease (AHR 1.17, 95% CI 0.50-2.75, P=.710). We observed very similar results within the SEER-Medicare cohort (favorable high-risk vs other high-risk: AHR 0.21, 95% CI 0.11-0.41, P<.001; favorable high-risk vs unfavorable intermediate-risk: AHR 0.67, 95% CI 0.33-1.36, P=.268). CONCLUSIONS: Patients with favorable high-risk prostate cancer have significantly better PCSM than other patients with high-risk disease and similar PCSM as those with unfavorable intermediate-risk disease, who are typically treated with shorter-course androgen deprivation therapy. This new classification system may allow for personalization of treatment within high-risk disease, such as consideration of shorter-course androgen deprivation therapy for favorable high-risk disease.