Human Papillomaviruses Are Identified in a Subgroup of Sinonasal Squamous Cell Carcinomas With Favorable Outcome

BACKGROUND: The role of human papillomavirus (HPV) in the pathogenesis of squamous cell carcinomas (SCCs) of the sinonasal tract and its clinicopathological implications were evaluated. METHODS: All SCCs of the sinonasal tract diagnosed in the Hospital Clinic of Barcelona from 1981 to 2006 were retrospectively evaluated (N = 60). Clinical and pathological data were reviewed. HPV infection was determined and typed by amplification of HPV DNA by polymerase chain reaction using the SPF-10 primers. p16(IN4a) expression was determined by immunohistochemistry. Overall and progression-free survival for HPV-positive and -negative patients was estimated by Kaplan-Meier analysis and by the use of a multivariate Cox proportional hazards model. RESULTS: HPV DNA was detected in tumor tissue of 12 of 60 (20%) patients. HPV16 was identified in 11 tumors and HPV35 in 1. Immunohistochemistry for p16(INK4a) stained all HPV-positive and no HPV-negative tumors (P<.001). No differences were observed in terms of site and histological grade or stage at presentation between HPV-positive and -negative tumors. However, HPV-positive patients had a significantly better 5-year progression-free survival (62%; 95% confidence interval [CI], 23%-86% vs 20%; 95% Cl, 9%-34%; P=.0043, log-rank test) and overall survival (80%; 95% CI, 20%-96% vs 31%; 95% CI, 15%47%; P=.036, log-rank test) than patients with HPV-negative tumors. In multivariate analysis, HPV-positive tumors were associated with improved progression-free survival (hazard ratio, 0.21; 95% CI, 0.17-0.98; P=.012). CONCLUSIONS: A subgroup of sinonasal SCCs is associated with HPV infection. These tumors have a significantly better prognosis. Cancer 2009;115:2701-9. (C) 2009 American Cancer Society.