KRAS and head and neck squamous cell carcinoma: When regarding HPV status, HPV-positive HNSCC showed similar TMB with HPV-negative cancers, whereas with different mutational landscape [21], generally, HPV-positive HNSCC exhibits rarer KRAS mutations and higher frequency of PIK3ca mutations that target the PI3K-AKTmTOR (PI3K) pathway; in particular, characteristic mutations including DDX3X, CYLD, and FGFR were also seen in HPV-positive HNSCC.