Survival of Patients with Muscle-Invasive Urothelial Cancer of the Bladder with Residual Disease at Time of Cystectomy: A Comparative Survival Analysis of Treatment Modalities in the National Cancer Database

Abstract

PURPOSE: Data have indicated that residual disease after neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC) may be associated with poor outcomes. OBJECTIVE: Analyze differences in overall survival (OS) of patients with residual MIBC treated with NAC + Radical cystectomy (RC), RC alone, or RC + Adjuvant Chemotherapy(AC). MATERIALS AND METHODS: The National Cancer Database was queried for patients who underwent RC alone, NAC + RC, or RC + AC for MIBC stage cT2-4aN0M0 from 2004-2015. Covariates were balanced using propensity score (PS) weighting. Time to death was evaluated from diagnosis. Weighted cox proportional hazards models and Kaplan-Meier survival curves were created to analyze differences in OS. RESULTS: 8,288 patients were included for analysis, 1,899 (23%) received NAC + RC, 5,529 (67%) received RC alone, and 860 (10%) received RC + AC. Patients were sub-stratified based on pathological staging (≤pT2 or >pT2) and compared against treatment with RC alone. In the ≤pT2 cohort, NAC + RC was associated with a decreased risk of death (HR:0.85, 95% CI:0.79–0.91) and RC + AC was associated with an increased risk of death (HR:1.46, 95% CI:1.34–1.60, both p < 0.001) compared to RC alone. In the >pT2 cohort, these associations reversed, with an increased risk of death seen in the NAC + RC group (HR:1.11, 95% CI:1.05–1.18) and a decreased risk of death in the RC + AC group (HR:0.74, 95% CI:0.7–0.77, both p < 0.001). CONCLUSIONS: Patients with >ypT2 disease after NAC experienced a significant increased risk of death when compared to pathological stage-matched patients who underwent RC alone or RC + AC. Biomarkers predictive of NAC resistance may be important to optimize NAC usage and establish treatment algorithms.