CD274 and esophageal squamous cell carcinoma: Based on these trials, the American Society of Clinical Oncology (ASCO) treatment guidelines for HER2-negative advanced gastroesophageal cancers are as follows: GAC/EAC/GEJ AC with PD-L1 CPS ≥ 5, nivolumab + chemotherapy is recommended; EAC/GEJ AC/ESCC with PD-L1 CPS ≥ 10, pembrolizumab + chemotherapy is recommended; ESCC with PD-L1 tumor proportion score (TPS) ≥ 1, nivolumab + chemotherapy or nivolumab + ipilimumab are recommended [41].