Prognostic risk factors of T2, T3, and T4 thoracic esophageal cancer and their relationship with improved survival after radiotherapy: A Retrospective Cohort Study

Background: This study aimed to investigate the prognostic risk factors of T2-T4 thoracic esophageal cancer and the survival benefit of common treatment modalities to provide a basis for selecting the most appropriate treatment. Methods: : This population-based retrospective cohort study collected data of patients diagnosed with T2-T4 thoracic esophageal cancer between 2010 and 2016 in the Surveillance, Epidemiology, and End Results database. Patients were divided according to those who had surgery and those who had radiotherapy. Survival curves were generated using the Kaplan–Meier (KM) method and compared using the log-rank test. Cox regression analysis was used to analyze the independent risk factors for prognosis. The effects of common treatment methods were analyzed according to their survival benefit. Results: : A total of 4998 patients were included. There was no significant difference in survival between the surgical and non-surgical groups (P=0.79). There was no significant difference in survival between those with T2 (P=0.47) and T4 (P=0.66) disease between the radiotherapy and non-radiotherapy groups, but there was between the radiotherapy and non-radiotherapy groups in patients with T3 disease (P=0.0019). Radiotherapy is an independent risk factor for the prognosis of T3 esophageal cancer, but not for T2 and T4 esophageal cancer. Conclusion: Surgery has no effect on survival in patients with T2-T4 thoracic esophageal cancer. Radiotherapy and T3 disease are independent prognostic risk factors for patients with T2-T4 thoracic esophageal cancer. These results provide a reliable basis for clinical treatment of patients with T2 -T4 thoracic esophageal cancer.