In this study, genetic polymorphisms of TNFRSF1B gene were evaluated Japanese esophageal squamous cell carcinoma (ESCC) patients treated with the definitive 5-FU/CDDP-based chemoradiotherapy and their predictive values of prognosis or severe acute toxicities were assessed. Here, TNFRSF1B is linked to esophageal squamous cell carcinoma.