PIK3CA and lip and oral cavity carcinoma: As described by Shigeishi (2023) [56], in HPV-positive oral cancers, mutations in the PIK3CA gene are frequently observed, while there are somatic mutations in ZNF750, FGFR3, DDX3X, CASZ1, PTEN, and CYLD, differentiating them from HPV-negative oral cancers.