Optimizing the use of androgen deprivation therapy in men with localized intermediate-risk prostate cancer in the era of modern dose-escalated radiation therapy.

109Background: While level one evidence has shown an overall survival (OS) advantage with the addition of androgen deprivation therapy (ADT) to radiotherapy (RT) for intermediate risk prostate cancer (PCa), the benefit in the era of modern dose escalation is controversial, especially given the heterogeneity within this risk group. We assessed the impact of adding ADT to high dose RT on OS for intermediate risk PCa stratified by number of intermediate risk factors (IRF). Methods: We identified 114,339 men with intermediate risk PCa (Gleason 7, clinical stage T1-2, PSA 10-20 ng/mL): A) Gleason 3+4 and no other IRF, B) Gleason 4+3 and no other IRF, C) two IRFs, and D) three IRFs. The addition of ADT to dose-escalated external beam RT (DE-EBRT, ≥ 75.6 Gy), brachytherapy (BT), or combination EBRT+BT on OS was assessed within each subgroup using Kaplan-Meier and ...