The results of the multifactor Cox regression model showed that TNM stage (stage III-IV) (HR = 1.961, 95% CI: 1.125 to 2.768), tumor hypofractionation (HR = 1.453, 95% CI: 1.034 to 2.857), presence of lymph node metastasis (HR = 1.499, 95% CI: 1.025 to 2.851), and DACH1 methylation (HR = 1.718, 95% CI: 1.067 to 2.596) may increase the risk of insensitivity to radiotherapy in patients with esophageal cancer (P < 0.05), as shown in Table 5. The gene discussed is DACH1; the disease is neoplasm.