Survival outcomes following radical cystectomy in patients with prior pelvic radiation for prostate cancer: A matched cohort analysis

Objectives: To determine the impact of prior pelvic radiation therapy (XRT) on outcomes following radical cystectomy (RC) for bladder cancer. Materials and methods: We performed a retrospective review comparing patients with bladder cancer requiring RC and prior history of XRT for prostate cancer to those undergoing RC without XRT history at our institution from 2011-2018. Propensity score matching was performed with the following variables: age, chronic kidney disease, nutritional deficiency, neoadjuvant chemotherapy use, Charlson comorbidity index, surgical approach, urinary diversion type, and pathologic T-stage. Perioperative, pathologic and oncologic outcomes were analyzed. Outcome measurements and statistical analysis: Categorical variables were assessed utilizing the Pearson Chi Square Test, and continuous variables with the Wilcoxon rank-sum test. The Kaplan-Meier method with stratified-log rank was used to compare survival outcomes. Multivariable Cox proportional hazards models were utilized to identify predictors of overall and recurrence free survival. Results: 227 patients were included, of which 47 had radiotherapy for prostate cancer. 47% of patients in the radiation cohort received external beam radiation therapy, 47% received brachytherapy and 7% received both. There were no differences in recurrence-free survival (P = 0.82) or overall survival (P = 0.25). Statistically significant differences in perioperative or postoperative outcomes such as 90-day complication, readmission, mortality rates, or ureteroenteric anastomotic stricture rates were not found. Rates of node-positive disease, median lymph node yield, positive surgical margin rates, lymphovascular invasion, or variant histology were not significantly different between cohorts. Conclusions: After matching for T-stage and other clinical variables, history of pelvic XRT for prostate cancer in patients who later required RC for bladder cancer, was not associated with an increased rate of perioperative complications or an independent predictor of RFS or OS.