CD274 and neoplasm: Additionally, limited analyses suggest variations in the response to immunotherapy between patients with HPV+OPSCC and HPV-OPSCC.6,7 This disparity may be attributed to the characteristics of the tumor microenvironment (TME) and to the actions of immunoregulatory agents, including programmed cell death receptor-1 (PD-1) and its ligand (PD-L1).8