Detection of Human Papillomavirus Infection in Cases of Oral Carcinoma Using p16 Immunohistochemistry

Background and aim  Oral cancer is a significant global health concern, with both high prevalence and mortality. In India, oral squamous cell carcinoma (OSCC) represents a large proportion of malignancies. Major risk factors include the use of tobacco and alcohol. High-risk human papillomavirus (HPV) infection has also been recognized as contributing to the development of oral cancers. This study aims to identify HPV infection in oral carcinoma cases using p16 immunohistochemistry (IHC) and to examine its relationship with the histological grading of the tumors. Materials and methods A one-year cross-sectional study of N = 50 cases of OSCC was conducted, and histological grading was performed according to the modified Broder's grading system. All OSCC cases were evaluated for p16 expression. Cases showing p16 positivity and its association with histological grading were analyzed. A p-value of <0.05 was considered statistically significant. Results Out of 50 cases, 48% (24/50) were positive for p16, of which 75% (18/24) were male, and 25% (6/24) were female. Among these 24 cases, histological grading showed that 4/24 cases were well differentiated, 19/24 cases were moderately differentiated, and 1/24 case was poorly differentiated. There was no statistically significant association between HPV infection and the histological grading of OSCC using p16 IHC (p-value = 0.304). Conclusions The present study revealed p16 positivity in 48% of OSCC cases, suggesting a low prevalence of HPV-infected OSCC in this region. The study also concluded that there is no statistically significant association between p16 expression and the histopathological grading of OSCC. A comparative study of p16 IHC and PCR is recommended for future studies to yield a more accurate and definitive diagnosis.