The ErbB receptor family includes specific transmembrane tyrosine kinase proteins: epidermal growth factor receptor, also known as ErbB1; ErbB2, also known as HER2; ErbB-3; and ErbB-4, all of which are overexpressed to varying degrees in human cancer including HNSCC.79 The gene discussed is ERBB2; the disease is head and neck squamous cell carcinoma.