CD274 and gastric cancer: Patients with metastatic or recurrent gastric cancer who had a PD-L1 combined positive score (CPS) of 1 or higher showed a significant objective response to pembrolizumab in the KEYNOTE-059 trial. Numerous trials, including KEYNOTE-061 and KEYNOTE-062, have assessed the use of pembrolizumab alone and in combination with chemotherapy [19].