Neoadjuvant Radiotherapy Improves Survival in Patients With T2b/T3 Bladder Cancer: A Population-Based Analysis

Abstract

Background: Neoadjuvant radiotherapy (NART) for muscle-invasive bladder cancer (MIBC) is currently underused. However, the outcomes for MIBC have remained suboptimal. We investigated the relationship of NART to cause-specific mortality (CSM) and overall mortality (OM) among patients with a diagnosis of MIBC.

Materials and methods: The patients diagnosed with primary invasive urothelial carcinoma of the bladder from 1983 to 2008 with localized disease were included. Patients aged > 90 years, those diagnosed with T1 or T4 BC, and those with no information on tumor grade were excluded from the analysis. Kaplan-Meier, Cox regression, and competing risk methods were used in the analysis of OM and CSM.

Results: A total of 5562 patients were included in the cohort (115 NART and 5447 surgery alone). On univariate analysis, NART significantly decreased the OM for patients with high-grade BC (hazard ratio [HR], 0.8), stage T2b (HR, 0.74), and stage T2b/T3 (HR, 0.74). CSM was also lower for those with stage T2b disease (HR, 0.63). Multivariable analysis revealed that NART was associated with a significant decrease in CSM (P = .043) and OM (P = .0462) for those with T2b. Likewise, an improvement was seen in OM (P = .0337) for patients with T2b/T3 who had received NART.

Conclusion: NART was significantly associated with decreased CSM and OM in patients with clinical T2b/T3 BC and OM for patients with T2b/T3. These data suggest that NART could be beneficial in patients with T2b/T3 BC. In the modern era, the greatest utility would potentially be for patients with an incomplete response to neoadjuvant chemotherapy or as an adjunct to chemotherapy to improve the complete response rates.

Keywords: Cause-specific mortality; Cystectomy; Overall mortality; SEER; Surgery.