Androgen deprivation with or without radiation therapy for clinically node-positive prostate cancer.

198 Background: Clinically lymph node positive (cN+) prostate cancer (PCa) is an often fatal disease. Its optimal management remains largely undefined given a lack of prospective, randomized data to inform practice. We sought to describe modern practice patterns in the management of cN+ PCa and assess the effect of adding radiation therapy (RT) to androgen deprivation therapy (ADT) on survival using the National Cancer Data Base. Methods: Patients with cN+ PCa with no distant metastases diagnosed between 2004-2011 were included. Five-year overall survival for patients diagnosed between 2004-2006 and treated with ADT alone or ADT+RT were compared. Propensity score (PS) matching was used to balance baseline characteristics and Cox multivariate regression analysis was used to estimate hazard ratios (HRs) for all-cause mortality. Results: 3,540 patients were included. 32.2% were treated with ADT alone and 51.4% received ADT+RT. Patients aged <65, those with private insurance, lower comorbidity scores, higher Gleason scores, and lower PSA values were significantly more likely to receive ADT+RT (p<.05). After PS matching, 318 patients remained in each group. Compared to ADT alone, ADT+RT was associated with a 50% decreased risk of five-year mortality (HR: 0.497, 95% CI: 0.37-0.67, p<.001). Conclusions: Using data recorded in a large national database, we have identified a significant survival benefit for patients with cN+ PCa treated with ADT+RT. These data, if appropriately validated, suggest that a significant proportion of such patients at high risk for prostate cancer death may be undertreated warranting a re-evaluation of current practice guidelines.