EGFR PROTEIN OVEREXPRESSION AND MUTATION IN ARECA QUID-ASSOCIATED ORAL CAVITY SQUAMOUS CELL CARCINOMA IN TAIWAN

Background. Epidermal growth factor receptor (EGFR)-targeted therapy has been extensively assessed in human cancer treatment. We appraised the possible role of tyrosine I inhibitors (TKIs) in areca quid (AQ)-associated oral cavity squamous cell carcinomas (OSCCs) by examining EGFR protein overexpression and its tyrosine kinase domain mutations. Methods. EGFR overexpression was evaluated by immuno-histochemical staining. and tyrosine kinase mutations was determined by direct sequencing of DNAs from 172 OSCC tumors. Results. Overexpression of I was found in 27.9% (48 of 172) of the OSCCs and was associated with lymph node metastasis (p=.013) and extracapsular spread (p=.022). Only 1 (0.58%) OSCC displayed somatic EGFR mutation but in a silent form (T725T, ACG-ACA). Conclusion. EGFR-targeted therapy might have some potential in AQ-associated OSCCs for their EGFR frequently overexpressed, although EGFR mutations were rare. However, the feasibility of TKIs in AO-associated OSCCs needs further clinical testing. (C) 2009 Wiley Periodicals, Inc. Head Neck 31: 1068-1077, 2009