CD274 and esophageal squamous cell carcinoma: In one recent Phase II study, it was shown that the use of a PD-L1 inhibitor-chemotherapy combination as the first-line treatment for patients with unresectable locally advanced ESCC resulted in impressive median OS (11.6 months) and overall response rate (ORR; 52.2%) values, an indication of the potential therapeutic efficacy of PD-L1 inhibitors for ESCC treatment [17].