(0682) Molecular Epidemiology of HPV Infection and Its Implications in the Etiology of Laryngeal Squamous Cell Carcinoma

Introduction: The role of Human Papilloma Vvirus (HPV) as an etiological factor in oropharyngeal SCC is well established but its contribution to laryngeal SCC remains unclear. We aimed to determine the prevalence of HPV DNA in laryngeal SCC samples and compare it to non-cancerous laryngeal specimens

Methods: We conducted a case-control study using retrospectively collected tissue specimens from 75 consecutive laryngeal squamous cell carcinoma patients, from which DNA could be extracted and from 75 laryngeal benign lesions. The 75 controls were selected from a pool of potential controls by use of matching to cases in relation to sex, age, and smoking habits. All samples were embedded in paraffin. HPV genotype, if present, was then determined.

Results: The prevalence of HPV was significantly higher in cases than controls (52 vs 9 cases, or 69.3% vs 12%, with an odds ratio (OR) 16.6 [95% CI)]. Specifically, the OR was 24 for the male population [OR (95% CI): 24 (8.9-64.9) p < 0.0005], 3 for the female population [OR (95%CI) :3 (0.5-20.2) p = 0.356], 19 for patients under 60 years of age [OR (95% CI) 18.9 (5.8-61.8) p < 0.0005] and 15 for patients over 60 years of age [OR (95% CI) :14.9 (4.3-51.4) p < 0.0005. There was no homogeneity of the OR between males and females (Breslow-Day test, p = 0.051) but there was homogeneity between age groups (Breslow-Day test, p = 0.786). Using a multiple logistic regression model with the enter method, we found a statistical significant impact of the HPV status on the presence of laryngeal cancer

Conclusions: These results suggest that prior infection with HPV may play a more important role in the etiology of laryngeal squamous cell carcinoma, than previously thought, at least for the local population studied.