EGFR and head and neck squamous cell carcinoma: Several ErbB-targeted therapies are currently under investigation for HNSCC treatment, including monoclonal antibodies or antibody-drug conjugates (e.g., cetuximab targeting EGFR and trastuzumab targeting HER2) or small-molecule tyrosine kinase inhibitors such as erlotinib for EGFR and lapatinib for EGFR and HER2, which usually require repeated administration.