EGFR and head and neck squamous cell carcinoma: Our cellular assays of viability and EGFR phosphorylation inhibition showed no specificity of direct cellular effects of the anti-EGFR antibody, while cetuximab binding tests and the in vitro ADCC experiments were in line with the theory that cetuximab might be more effective against EGFR 521 wild-type HNSCC cells.