HPV and Oropharyngeal Carcinoma - A Histomorphological Analysis

Introduction: HPV associated oropharyngeal carcinomas are of great importance nowadays because of its differing behavior irrespective of the tumor differentiation. The aim of this study is to analyse the incidence of HPV associated oropharyngeal carcinoma in our institute and various histomorphological features associated with these tumors. Materials and Methods: This is a retrospective study conducted in Department of Pathology, Thanjavur Medical College. All cases of oropharyngeal squamous cell carcinoma which meets the inclusion and exclusion criteria during 1year study period were included. The clinical parameters were retrieved and histomorphological features were analysed in H&E stained sections. Immunohistochemical analysis of p16marker was done and compared with the clinical and histopathological details. Results: Of the 50 cases included in the study, 80% occur in male and 44% occur in tonsil and tonsillar fossa. 60% cases are keratinizing SCC and 34% cases have good lymphocytic response. P16 positivity is seen in 46% cases. 60.9% cases of HPV positive tumors are nonkeratinising. Lymphocytic response is present more in HPV positive tumors compared to HPV negative tumors. All HPV associated tumors have low Worst pattern of invasion. Discussion and Conclusion: HPV associated tumors are most common in the oropharynx and they have better prognosis with increased response to therapy. HPV positive tumors are more common in tonsil because it is the easily accessible lymphoepitheial site for the entry of organism and they exhibit greater CD8 positive T cell infiltrate. Our study also showed statistically significant association between good Tumor infiltrating lymphocytes, absence of keratin and HPV positivity. In conclusion HPV positive tumors are associated with better pathologic prognostic factors.