Abstract
INTRODUCTION: Patients with esophageal cancer who are in a poor general condition receive radiotherapy alone, but outcomes are often unsatisfactory. The aim of this study was to clarify recent outcomes of radiotherapy alone for esophageal cancer. METHODS: Patients who underwent 50 Gy or more of radiotherapy without chemotherapy were retrospectively reviewed. Endpoints were overall survival (OS), disease-specific survival (DSS), local control (LC), and progression-free survival (PFS). Survival curves were drawn using the Kaplan-Meier method, and predictors were analyzed using the Cox proportional hazards model. RESULTS: Sixty-nine patients were included. The median follow-up period was 17.9 months. The 5-year OS, DSS, LC, and PFS rates were 33.2%, 49.8%, 46.2%, and 16.8%, respectively. In the multivariate Cox proportional hazard model, clinical stage was a significant predictor for OS (hazard ratio [HR]: 4.42, 95% confidence interval [CI]: 1.80-11.17, p = 0.001), DSS (HR: 2.08, 95% CI: 1.43-3.12, p = 0.0001), LC (HR: 1.86, 95% CI: 1.28-2.74, p = 0.001), and PFS (HR: 1.65, 95% CI: 1.25-2.18, p = 0.0004). Radiation dose was a significant predictor for LC (HR: 0.87, 95% CI: 0.78-0.97, p = 0.018) and tumor location was a significant predictor for PFS (HR: 1.55, 95% CI: 1.10-2.19, p = 0.018). In subgroup analysis, the 5-year OS, DSS, LC, and PFS rates for stage I were 60.0%, 80.0%, 71.9%, and 46.1%, respectively. CONCLUSIONS: Stage, radiation dose, and tumor location are significant predictors for outcomes. Patients with stage I esophageal cancer can be cured by radiotherapy alone.