Survival analysis for patients with T_4b squamous cell carcinoma of thoracic esophagus receiving concurrent chemoradiotherapy

Objective: We aimed to analyze the clinical efficacy and treatment-related complications in patients with T_4b esophageal squamous cell carcinoma (SCC) who received concurrent CRT, and to explore the potential prognostic factors related to survival. Methods: Between 2010 and 2015, 143 patients with T_4b esophageal SCC treated with CRT were analyzed, including 71% patients with trachea and/or bronchus invasion and 44% patients with aorta and/or large vessel invasion. The median radiation dose was 60 Gy (range, 44-68 Gy ) with conventional fractionation, including 69 patients (48%) treated with three-dimensional conformal radiotherapy and 74 patients (52%) treated with intensity-modulated radiotherapy. All patients received concurrent platinum-based chemotherapy during radiotherapy. Kaplan-Meier method was used to analyze the survival, the log-rank test was used to examine group differences, and the Cox regression model was used for multivariate analysis. Results: The median overall survival (OS) time for the whole cohort was 12.2 months. The 2- and 3- year OS rates were 34% and 29%, respectively. A total of 51 patients experienced ≥ 2 severe non-hematological complications, including 42 esophageal fistula, 6 pneumonia, and 3 esophageal hemorrhage. Patients with severe complications showed significantly worse survival than those without complications (6.9 months vs. 20.4 months, P < 0.01). Multivariate analysis revealed that TNM stage and severe complications were independent prognostic factors for OS. Conclusions: Patients with T_4b esophageal SCC who received CRT showed satisfactory survival but with high risk of severe complications. Therefore, prevention and treatment of severe complications is the key to improve efficacy. (authors)