PDCD1 and esophageal squamous cell carcinoma: In our study, we found that PD‐1 inhibitor combined with various treatments including chemotherapy, anti‐EGFR, anti‐angiogenesis (surufatinib, anlotinib, and apatinib), anti‐TIGIT therapies, and radiotherapy demonstrated synergistic efficacy in the second‐ or later‐line treatment of advanced ESCC.