CD274 and head and neck squamous cell carcinoma: The PD-L1 inhibitor durvalumab in combination with the CTLA-4 inhibitor tremelimumab has been studied in both the first-(CONDOR, EAGLE) and subsequent-line settings (KESTREL) for advanced HNSCC, with no differences in efficacy compared to standard therapy and no evident difference by HPV status [82,83,84].