In suspected head and neck CMs, the immunohistochemical panel should include CK5/6 and EMA for squamous differentiation, p16 immunostaining as a surrogate for high-risk HPV infection (particularly in oropharyngeal primary tumors), and EGFR (epidermal growth factor receptor), which is commonly overexpressed in head and neck squamous cell carcinoma and can further support the diagnosis [16,139,140,141,142,143]. This evidence concerns the gene EGFR and head and neck squamous cell carcinoma.