Neoadjuvant chemoradiation radiation dose levels for surgically resectable esophageal cancer: predictors of use and outcomes.

Abstract

Neoadjuvant chemoradiation (CRT) followed by surgical resection is the standard of care for resectable, locally advanced esophageal cancer. There are promising results using 41.4 Gy relative to historical controls using higher doses, but the utilization and efficacy of lower neoadjuvant radiation dosing is unclear. This study uses the National Cancer Database (NCDB) to explore patterns of care for neoadjuvant CRT dose levels and outcomes. The NCDB was queried for localized invasive esophageal adenocarcinoma (AC) or squamous cell carcinoma (SCC) receiving neoadjuvant CRT with doses from 40 to 54 Gy followed by surgical resection. Patients were divided into radiation levels: 40-41.4, 45, 50.4, and 54 Gy, respectively. Factors predicting use of 40-41.4 Gy vs. all other dose levels were compared using multivariable logistic regression. Factors affecting overall survival (OS) were compared using univariate and multivariate modeling. A total of 6,274 patients with AC (n=5,176) or SCC (n=1,098) receiving neoadjuvant CRT and definitive resection were identified. Hispanic race (OR 2.67 [95% CI 1.22-5.81]) and treatment at an academic center (OR 2.72 [95% CI 1.15-6.41]) predicted for use of low-dose CRT. Lower dose CRT increased from 3.9% in 2004 to 7.2% in 2013. There was no difference in OS when stratified according to radiation dose level (P=0.48). Multivariable analysis found private/government insurance, higher education, higher median income, and treatment at an academic center were associated with improved OS. Age, male gender, Charlson-Deyo comorbidity score, stage, tumor grade, and treatment in the South were associated with worse OS. Use of lower neoadjuvant CRT dose is more common at academic centers and shows possible increasing usage. Neoadjuvant radiation dose for esophageal cancer is not associated with differences in OS in this large database.