CD274 and nasopharyngeal carcinoma: In the previous phase 1b KEYNOTE-028((NCT02054806) trial,(8) pembrolizumab treatment of those patients with RM-NPC who were PD-L1 positive resulted in 7 (25.9%) of the 27 PD-L1 positive patients with NPC achieving partial remission, 14 patients remained in a stable condition, but no patients showed complete remission.