Regarding PD-L1 inhibitors, durvalumab and tremelimumab (a CTLA-4 inhibitor) combined with concurrent chemoradiotherapy (CCRT) are effective in patients with locally terminal ESCC [38], while adebrelimab combined with chemotherapy has shown good efficacy and safety in the first-line treatment of patients with locally advanced or metastatic ESCC [39]. This evidence concerns the gene CTLA4 and esophageal squamous cell carcinoma.