Study on the Association of HPV Subtypes with Oral Squamous Cell Carcinoma.

Background: Oral squamous cell carcinoma (OSCC) is a major public health concern with rising incidence globally. Human papillomavirus (HPV), particularly high-risk subtypes, has been implicated as a possible etiological factor, but the distribution and prevalence of specific subtypes in OSCC remain variable across populations. Methods: A cross-sectional analytical study was conducted on 120 histopathologically confirmed OSCC cases and 80 age- and sex-matched healthy controls. DNA was extracted from formalin-fixed paraffin-embedded tumor tissue and control oral mucosal scrapings. Polymerase chain reaction (PCR) with type-specific primers was used to detect HPV DNA. The identified HPV-positive samples were genotyped for subtypes 6, 11, 16, 18, 31, and 33. Statistical analysis was performed using Chi-square and logistic regression, with significance set at P < 0.05. Results: Overall HPV positivity was significantly higher in OSCC cases (42.5%) than controls (11.3%) (P < 0.001). High-risk HPV-16 was the most prevalent subtype among cases (28.3%), followed by HPV-18 (9.2%), HPV-33 (3.3%), and HPV-31 (1.7%). Low-risk subtypes HPV-6 and HPV-11 were rare in cases (both 0.8%). In controls, HPV-16 was detected in only 5.0% of subjects. Logistic regression showed HPV-16 positivity was associated with a 6.8-fold increased OSCC risk (95% CI: 3.1-14.7, P < 0.001). Mean age of HPV-positive OSCC patients was 53.6 ± 9.8 years, with a male predominance (M: F ratio 2.4:1). Conclusion: High-risk HPV subtypes, particularly HPV-16 and HPV-18, show a strong association with OSCC, highlighting the potential role of HPV vaccination and targeted screening programs in high-incidence regions.