Trends and Predictors of Hypofractionated and Intensity-Modulated Radiotherapy for Organ Preservation in Bladder Cancer. Clinical genitourinary cancer Xiang, M., Chang, A. J., Chamie, K., Drakaki, A., Pollom, E. L., Steinberg, M. L., Kishan, A. U. 2021

Abstract

INTRODUCTION: Use of hypofractionated radiation (HFRT) and intensity-modulated radiation (IMRT) for organ preservation in bladder cancer is controversial and highly variable. We investigated practice patterns, trends, and predictors of HFRT and IMRT.PATIENTS AND METHODS: The National Cancer Database was queried for patients with muscle-invasive, non-metastatic urothelial bladder cancer, treated with definitive (chemo)radiotherapy between 2004 and 2017. HFRT was defined as 50 to 60 Gy at >2 Gy/fraction. Multivariable logistic regression was used to identify predictors of receiving HFRT or IMRT. Multivariable Cox regression was used to model overall survival (OS), adjusting for potential confounders such as age, comorbidity, and chemotherapy.RESULTS: Of 5132 patients identified, 490 (9.5%) received HFRT, and only 334 (6.5%) received =2.5 Gy/fraction. HFRT patients were significantly older, less fit, and less likely to receive chemotherapy relative to CFRT, even after controlling for age and comorbidity (adjusted odds ratio 0.36, 95% confidence interval [CI] 0.29-0.45, P < .0001). Utilization of HFRT and IMRT increased over time (P < .0001), reaching 22.5% and 47.7%, respectively, by 2017. Among patients treated with CFRT, OS was similar with or without IMRT (P=.46). Among patients treated with HFRT, IMRT was associated with increased survival (3-year OS 35% vs. 24%, P=.03), which persisted in multivariable analysis (adjusted hazard ratio 0.71, 95% CI 0.52-0.98, P=.04).CONCLUSION: HFRT is largely underutilized, being primarily reserved for older, frailer patients. Chemotherapy is significantly underused with HFRT relative to CFRT. IMRT is used frequently and was associated with equivalent or modestly increased overall survival.

View details for DOI 10.1016/j.clgc.2021.11.002

View details for PubMedID 34866018