Prognosis of different irradiation methods in patients with T_2-3N₀M₀ esophageal squamous cell carcinoma

Objective: To evaluate the effect of different irradiation methods on the long-term prognosis of patients with clinical T_2-3N₀M₀ esophageal squamous cell carcinoma, aiming to select the optimal treatment for these patients. Methods: A total of 268 eligible patients admitted to our hospital from January 2007 to December 2012 were enrolled in this study. All patients were divided into the involved-field irradiation (IFI) and elective node irradiation (ENI) groups. The composition ratio, prognostic factors and adverse events were analyzed between two groups. Results: The median overall survival (OS) time was 35.5 months (95%CI: 30.12-40.88) and the median disease-free survival (DFS) time was 23.5 months (95%CI: 19.00-28.00). According to the multivariate analysis results, all patients were assigned into two groups at a ratio of 1 vs. 1 (n = 86 in each group). Multivariate analysis after propensity score matching (PSM) demonstrated that irradiation method was the independent factor of OS (P = 0.038), and T stage and radiotherapy were the independent factors affecting DFS (P = 0.002, 0.032). The incidence of ≥ grade II adverse events did not significantly differ between two groups (P = 0.819, 0.756). However, patients with combined chemotherapy experienced more adverse events. Conclusion: ENI can prolong the OS and DFS of patients with clinical T_2-3N_oM_o esophageal squamous cell carcinoma, and does not increase the incidence of severe adverse events. (authors)