For patients with advanced esophageal squamous carcinoma (ESCC), the efficacy of programmed cell death protein 1 (PD-1) monotherapy remained limited: overall survival (OS) was ≤  9 months and median progression-free survival (PFS) was not prolonged compared with chemotherapy [2, 3]. This evidence concerns the gene PDCD1 and esophageal squamous cell carcinoma.