P31 Prevalence of human papillomavirus in laryngeal and hypopharyngeal squamous cell carcinomas

Abstract

Background Recent studies support a role for human papillomavirus (HPV) in oropharyngeal squamous cell carcinomas (SCCs); however, the significance of HPV in non-oropharyngeal head and neck cancers is uncertain. In addition, the incidence varies widely depending on the geographic location and time period studied. The aim of this study was to determine the prevalence of HPV in a large cohort of oropharyngeal, laryngeal and hypopharyngeal SCCs in northern Spain. Methods Clinical records and paraffin-embedded tumor specimens of consecutive patients surgically treated for oropharyngeal (248 cases), laryngeal (62 cases) and hypopharyngeal (62 cases) SCCs between 1990 and 2009 were retrieved. All cases were histologically evaluated, and presence of HPV was assessed by p16INK4A-immunohistochemistry followed by GP5+/6+-PCR-based DNA detection. Samples positive in both assays were subjected to HPV genotyping and HPV E6 transcript analysis. Results Immunostaining of p16 INK4A was positive for 30/248 (12%) oropharyngeal, 14/62 (23%) laryngeal and 3/62 (5%) hypopharyngeal SCC. Subsequent GP5+6+-PCR on these cases showed presence of HPV type 16 DNA in 8 (3.2%) oropharyngeal and in 1 case (1.6%) each of larungeal and hypopharyngeal SCC. Conclusions Patients in northern Spain demonstrated a low HPV involvement in oropharyngeal SCC patients in northern Spain is very low and occurs only occasionally in laryngeal and hypopharyngeal SCC.