Dose escalation of definitive radiation is not associated with improved survival for cervical esophageal cancer: a National Cancer Data Base (NCDB) analysis.

Abstract

For cervical esophageal cancer (CEC), National Comprehensive Cancer Network guidelines support RT to 50-50.4 Gy with chemotherapy but acknowledge higher doses may be appropriate. This study uses the National Cancer Database (NCDB) to characterize RT practices and identify if a dose-response relationship exists for overall survival (OS) for definitive treatment of CEC. We queried the NCDB for patients diagnosed with Stage I-III CEC from 2004 to 2013, and selected patients receiving definitive RT with doses between 50 and 74 Gy. Using multivariate logistic regression, the database was analyzed to determine factors associated with use of RT > 50.4 Gy. Patients were then stratified into three dose categories. Predictors of OS were analyzed with univariate and multivariate methods using the Kaplan-Meier curves, the log-rank test, and the Cox proportional hazards analysis. We stratified 789 patients with CEC who were treated with definitive radiation ± chemotherapy: 50-50.4 Gy ('standard'), >50.4 and <66 Gy ('medium'), and 66-74 Gy ('high'). Of these patients, 215 (27%) received standard doses, 375 (48%) received medium doses, and 199 (25%) received high doses. Patients with Medicaid insurance and those with Stage II disease were less likely (P < 0.05) to receive >50.4 Gy. Sex, histology, distance to treatment facility, and academic/community facility type were not significantly associated with receipt of >50.4 Gy. There was no association between dose and OS for the medium or high groups when using univariate analysis or analysis adjusted for demographic, facility, and clinical attributes. Stage III disease and the Charlson-Deyo scores of 1 or 2 were associated with higher mortality (P < 0.05), while female sex and use of chemotherapy were associated with lower mortality (P < 0.01). Nearly three-fourths of CEC patients in the United States are treated with RT > 50.4 Gy. Higher radiation doses were not associated with increased OS in CEC patients in the NCDB.