EGFR mutations and human papillomavirus in squamous cell carcinoma of tongue and tonsil

Abstract

10027 Background: Some studies reported the presence of somatic mutation of EGFR in head and neck cancer. Human papillomavirus (HPV) was associated with some types of head and neck cancer. We performed this study to determine clinical significance of EGFR mutation and its association with HPV infection in patients with tongue and tonsil cancer. Methods: We sequenced exons 18–21 of EGFR TK domain and HPV typing was performed using the HPV DNA chip in tissues of patients with tongue and tonsil cancer. Univariate and multivariate analysis was performed. Results: Eighty-one patients were included. We detected EGFR mutation in 10 (12%) patients. Mutation was significantly frequent in never-smoker (21% versus 5%; P = 0.031). The mutation frequency did not differ between tongue and tonsil cancer (12% vs. 13%, respectively; P = 0.978). There was no difference between female and male (12% vs. 14%, respectively; P = 0.754). Eleven of 81 (14%) patients were HPV positive. HPV positivity was more common in young (<60 years) than older (≥60 years) patients (20% vs. 3%, respectively; P = 0.039). Patients with tonsil cancer showed more frequent HPV positivity than tongue cancer (42% vs. 2%, respectively; P < 0.001). There was no association between HPV positivity and EGFR mutation. In terms of disease-free survival, patients with EGFR mutation had better survival independently of stage and primary site (hazard ratio, 0.246; 95% CI, 0.075 to 0.802). Conclusions: We did not find association between EGFR mutation and HPV positivity. Patients with EGFR mutation showed better outcome in tongue and tonsil cancer. These results suggest that EGFR mutation may be a prognostic factor in patients with head and neck cancer. No significant financial relationships to disclose.