Effectiveness of postoperative radiotherapy after radical cystectomy for locally advanced bladder cancer.

Local-regional failure (LF) for locally advanced bladder cancer (LABC) after radical cystectomy (RC) is common even with chemotherapy and is associated with high morbidity/mortality. Postoperative radiotherapy (PORT) can reduce LF and may enhance overall survival (OS) but has no defined role. We hypothesized that the addition of PORT would improve OS in LABC in a large nationwide oncology database.

We identified ≥ pT3pN0-3M0 LABC patients in the National Cancer Database diagnosed 2004-2014 who underwent RC ± PORT. OS was calculated using Kaplan-Meier and Cox proportional hazards regression modeling was used to identify predictors of OS. Propensity matching was performed to match RC patients who received PORT vs those who did not.

15,124 RC patients were identified with 512 (3.3%) receiving PORT. Median OS was 20.0 months (95% CI, 18.2-21.8) for PORT vs 20.8 months (95% CI, 20.3-21.3) for no PORT (P = 0.178). In multivariable analysis, PORT was independently associated with improved OS: hazard ratio 0.87 (95% CI, 0.78-0.97); P = 0.008. A one-to-three propensity match yielded 1,858 patients (24.9% receiving PORT and 75.1% without). In the propensity-matched cohort, median OS was 19.8 months (95% CI, 18.0-21.6) for PORT vs 16.9 months (95% CI, 15.6-18.1) for no PORT (P = 0.030). In the propensity-matched cohort of urothelial carcinoma patients (N = 1,460), PORT was associated with improved OS for pT4, pN+, and positive margins (P < 0.01 all).

In this observational cohort, PORT was associated with improved OS in LABC. While the data should be interpreted cautiously, these results lend support to the use of PORT in selected patients with LABC, regardless of histology. Prospective trials of PORT are warranted.

Cancer medicine. 2019 May 22 [Epub ahead of print]

Benjamin W Fischer-Valuck, Jeff M Michalski, Nandita Mitra, John P Christodouleas, Todd A DeWees, Eric Kim, Zachary L Smith, Gerald L Andriole, Vivek Arora, Arnold Bullock, Ruben Carmona, Robert S Figenshau, Robert L Grubb, Thomas J Guzzo, Eric M Knoche, S Bruce Malkowicz, Ronac Mamtani, Russell K Pachynski, Bruce J Roth, Mohamed S Zaghloul, Hiram A Gay, Brian C Baumann

Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri., Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, Pennsylvania., Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania., Department of Urology, Washington University in St. Louis, St. Louis, Missouri., Department of Medical Oncology, Washington University in St. Louis, St. Louis, Missouri., Department of Urology, University of Pennsylvania, Philadelphia, Pennsylvania., Department of Medical Oncology, University of Pennsylvania, Philadelphia, Pennsylvania., National Cancer Institute, Cairo University, Cairo, Egypt.