Perioperative Morbidity of Robotic-Assisted Radical Cystectomy Versus Open Radical Cystectomy in Older Adults and the...

To examine the role of frailty as a potential effect modifier of the comparative effectiveness of robotic-assisted radical cystectomy (RARC) and open radical cystectomy (ORC) in older adults. Radical cystectomy (RC) is associated with high rates of perioperative morbidity, and frailty may serve as a potentially strong modifier of both perioperative and oncologic outcomes. We therefore emulated a pragmatic clinical trial of RARC versus ORC to examine this question.

We identified adults 66-89 years with Tis-T4 / N0-N1 / M0 urothelial carcinoma of bladder from 2008 to 2017 treated with RC in SEER-Medicare. Baseline frailty was assessed using the claims-based frailty index (CFI). Associations of RARC and ORC with perioperative and oncologic outcomes were examined in the overall cohort after stabilized inverse probability of treatment re-weighting (sIPW). Baseline frailty was examined as an effect modifier using interaction terms in separate models.

A total of 1,750 patients were included in the study cohort, of whom 229 underwent RARC and 1521 underwent ORC. Adjusted rates of perioperative blood transfusion or 90-day ER utilization, hospital readmission, and complications were not statistically significantly different between RARC and ORC. Similarly, there were no statistically significant differences in cancer-specific or all-cause mortality. Notably, there were no statistically significant differences in perioperative morbidity or oncologic outcomes across baseline frailty level.

In observational analyses designed to emulate the iROC trial, RARC was not associated with improved perioperative morbidity or oncologic outcomes in older adults, regardless of baseline frailty level.