NFE2L2 and esophageal squamous cell carcinoma: Previous studies have demonstrated that high expression of Nrf2 is involved in the mechanisms of radioresistance of esophageal cancer, breast cancer, prostate cancer and lung cancer.25, 26, 27, 28, 29, 30, 31 The study by Kawasaki et al. 30 proved that the expression level of Nrf2 could predict the treatment response and long‐term prognosis of ESCC patients after CCRT.