Increased expression of epidermal growth factor receptor in normal epithelium adjacent to head and neck carcinomas independent of tobacco and alcohol abuse.

OBJECTIVE In this study we examined if expression of the epidermal growth factor receptor (EGFR) in normal epithelium adjacent to head and neck squamous cell carcinomas (HNSCC) is increased and if this increase is due to the use of tobacco and alcohol. MATERIALS AND METHODS: Cut sections of formalin-fixed and paraffin-embedded material of histologically normal epithelium adjacent to HNSCC from 25 patients who smoke excessively and abuse alcohol, and 17 HNSCC patients who do not abuse tobacco and alcohol were compared with cut sections of normal epithelium from 27 control individuals. The sections were immu-nohistochemically stained for the EGFR. RESULTS: We show an elevation of the expression of the EGFR in patients who smoke and drink excessively, that could also be ascertained, to a lesser extent, in patients that do not have a history of smoking or drinking (P = 0.08). We also find that the closer the epithelium lies to the HNSCC the higher the expression of the EGFR is. CONCLUSIONS: Expression of the EGFR is increased in tumour-adjacent epithelium and this is not only due to the use of tobacco and/or alcohol. We suggest that paracrine effects of the HNSCC and migration of tumour cells may also play a role in this increased expression.