PREVALENCE OF HUMAN PAPILLOMA VIRUS IN A TERTIARY CARE CENTRE IN CENTRAL INDIA USING p16 IMMUNOEXPRESSION AS A SURROGATE MARKER

BACKGROUND High risk Human Papilloma Virus (HR-HPV) has now emerged as one of the major etiological factors in oral and oropharyngeal cancer. Knowing HPV status is crucial as it has a significant impact on therapeutic front as well as on prognosis. As p16 immunoexpression can serve as surrogate marker for HR-HPV infection, in the current study we used p16 immunoexpression to determine the prevalence of HPV in a tertiary care centre in Central India. MATERIALS AND METHODS This is hospital based cross sectional study conducted in oral biopsy tissues (for neoplastic lesions) received for histopathological evaluation over a period of one and half years. The sections were processed for H & E staining, and 112 cases were chosen for immunohistochemical study. The data was analysed by chi-square and Z-tests using software SPSS. RESULTS Positive diffuse p16 immunoexpression was present in 23.2% of the cases irrespective of histological type/grade of the lesion. We found significant correlation between degree of dysplasia and p16 immunoexpression with 16.7% of cases showing positivity in OIN I cases as compared to 25% in OIN II and 77.8 % in OIN III. Poorly differentiated tumours had high proportion of cases with positive p16 immunoexpression (75%) compared to well differentiated (29.3%) and moderately differentiated squamous cell carcinomas (35.5%). Additionally, higher proportion of female patients (43.8%) had diffuse p16 positivity than males (17%). CONCLUSION We conclude that HPV prevalence in our tertiary care centre is approximately 23.2%. This subset of cases was found to be associated more with oropharyngeal lesions and was present in higher proportions in female patients. Apart from serving as a surrogate marker for HR-HPV, p16 immunoexpression also correlates with the degree of dysplasia in oral and oropharyngeal lesions.