Chemotherapy Versus Chemoradiation for Node-Positive Bladder Cancer: Practice Patterns and Outcomes from the National Cancer Data Base

Background: Management of clinically node-positive bladder cancer (cN+ BC) is poorly defined; national guidelines recommend chemotherapy (CT) alone or chemoradiation (CRT). Objective: Using a large, contemporary dataset, we evaluated national practice patterns and outcomes of CT versus CRT to elucidate the optimal therapy for this patient population. Methods: The National Cancer Data Base (NCDB) was queried (2004-2013) for patients diagnosed with cT_anyN1-3M0 BC. Patients were divided into two groups: CT alone or CRT. Statistics included multivariable logistic regression to determine factors predictive of receiving additional radiotherapy, Kaplan-Meier analysis to evaluate overall survival (OS), and Cox proportional hazards modeling to determine variables associated with OS. Propensity score matching was performed to assess groups in a balanced manner while reducing indication biases. Results: Of 1,783 total patients, 1,388 (77.8%) underwent CT alone, and 395 (22.2%) CRT. Although patients receiving CRT tended to be of higher socioeconomic status, they were more likely older (p = 0.053), higher T stage, N1 (versus N2) disease, squamous histology, and treated at a non-academic center (p < 0.05). Median overall survival (OS) was 19.0 months and 13.8 months (p < 0.001) for patients receiving CRT or CT, respectively. On Cox multivariate analysis, receipt of CRT was independently associated with improved survival (p < 0.001). Outcome improvements with CRT persisted on evaluation of propensity-matched populations (p < 0.001). Conclusions: CRT is underutilized in the United States for cN+ BC but is independently associated with improved survival despite being preferentially administered to a somewhat higher-risk population.