The impact of prior external beam radiation therapy on device outcomes following artificial urinary sphincter revision surgery

Background: Previous reports on the effect of radiation therapy on primary artificial urinary sphincter (AUS) device survival have met with conflicting results, and data evaluating this after revision surgery is sparse. Thus, we evaluated AUS device outcomes after revision surgery, and compared them among individuals who did versus did not undergo prior radiation therapy. Methods: A database of patients who underwent AUS revision surgery at our institution was used to perform a retrospective review. Device survival endpoints, including overall survival, infection/erosion, urethral atrophy, and device malfunction were evaluated. Overall device survival (i.e., any repeat surgery) was compared between groups, stratified by external beam radiation status, via Kaplan-Meier method. Proportional hazard regression and competing risk analysis were used to evaluate association between prior radiation therapy and device outcomes. Results: From 1983 to 2016, a total of 527 patients underwent AUS revision surgery. Of these, 173 (33%) patients had undergone prior radiation therapy. Patients with prior radiation therapy were more likely to have diabetes mellitus (22% vs . 14%; P=0.05), hypertension (70% vs . 56%; P vs . 19%; P vs . 6%; P vs . 85% and 50% vs . 64%, respectively (P=0.08). On competing risk analysis, a history of pelvic radiation therapy was not enough evidence to support a significant association with the risk of device infection/erosion, mechanical failure, or urethral atrophy. Conclusions: There was not enough evidence of a difference in the rate of device erosion or infection, cuff atrophy, malfunction, or overall device survival following AUS revision surgery between patients with and without a history of pelvic radiation. These findings may be helpful when counseling patients regarding outcomes after AUS revision.