484 Background: Robot-assisted radical cystectomy (RARC) has been shown to have comparable oncologic efficacy compared to open radical cystectomy (ORC). We sought to compare the rates of benign strictures after RARC and ORC using a population-based data. Methods: From Surveillance, Epidemiology, and End Results (SEER)-Medicare, we identified 332 RARC and 1449 ORC performed during 2009 and 2014, using International Classification of Diseases-9th edition and Current Procedural Terminology 4th edition to compare the development of ureteroenteric strictures at 6 months, 1 year and 2 years following radical cystectomy. We defined ureteroenteric stricture as the need for procedural intervention, consistent with prior studies. Additionally, we compared the incidence of stricture diagnosis. Multivariable proportional hazards regression was performed to determine factors associated with stricture development. Results: The incidence of ureteroenteric stricture at 6 months and 12 was higher for RARC vs. ORC at 12.1% vs. 7.0% (p<0.01) and 15.0% vs. 9.5% (p=0.01), respectively. However, the RARC vs. ORC stricture incidence at 2 years did not differ significantly at 14.6% vs. 11.4% (p=0.29). Similarly, the stricture diagnosis rates were significantly lower following ORC at 6, 12, and 24 months (p<0.05). In adjusted analysis, RARC (HR 1.70, 95% CI 1.28-2.26) and pre-operative hydronephrosis (HR 1.48, 95% CI 1.15-1.91) were associated with the development of stricture. Conversely, higher hospital volume was associated with a lower risk of stricture (HR 0.43, 95% CI 0.29-0.63). Conclusions: RARC is associated with a higher rate of post-radical cystectomy stricture complication diagnosis and intervention on a population-based level that is mitigated by higher hospital volume. Technical factors are likely responsible and prospective studies are needed to assess the influence of ureteral dissection, tissue handling and perfusion, redundancy, and/or tension on the anastomosis. A significant study limitation is the inability to differentiate extracorporeal versus intracorporeal diversion with our use of administrative data.
MP41-07 COMPARISON OF URETEROENTERIC STRICTURE RATES AFTER ROBOT-ASSISTED RADICAL CYSTECTOMY
