CEBPA and head and neck squamous cell carcinoma: Mutations in CEBPA (CCAAT/enhancer-binding protein alpha), a tumor suppressor gene mutated in different tumors [27], have not been previously reported in HNSCC, and although the pR323G mutation found in CEBPA protein lies in a highly mutated leucine zipper domain, the R323 substitution has not been previously reported [22, 28].