Objective: To determine the prevalence and describe the clinical characteristics of high risk HPV mong patients with oropharyngeal squamous cell carcinomas in our institution utilizing p16 and HPV DNA in-situ hybridization testing and to determine the factors associated with high risk HPV positivity. Methods: Design: Retrospective Cohort Review Setting: Tertiary Private Training Hospital Participants: 29 Results: A total of 29 primary oropharyngeal squamous cell carcinomas were diagnosed during the 11-year study period (January 2010 to December 2021). Based on the HPV in-situ hybridization status, the prevalence of high risk HPV oropharyngeal squamous cell carcinoma in our institution was 52%. Majority of these cases were males (87.5%) with a median age of ≤55 years old (60%) who are non-smokers (88.2%) and non-drinkers of alcoholic beverages (80%). There was no statistically significant association between age group, sex, smoking status, alcohol intake, lymph node status and high risk HPV infection. The most common tumor site involved in HPV-positive oropharyngeal squamous cell carcinoma was the tonsil (87%). Majority demonstrated a nonkeratinizing histology (73%) with positive lymph node status (67%) upon clinical presentation. Fifteen (83%) of the 18 p16 positive squamous cell carcinomas were positive for high risk HPVDNA. Of note, 3 (17%) out of the 18 p16 positive squamous cell carcinomas turned out to have negative HPV DNA-ISH status. Conclusion Although no statistically significant correlation between any clinical characteristic with viral status was established, HPV-mediated oropharyngeal squamous cell carcinoma in this institution was commonly seen among males aged 54 years old and below who are nonsmokers and non-drinkers of alcoholic beverages with the palatine tonsil as the most common site presenting with a non-keratinizing histology. In terms of testing, p16 staining correlates well with high risk HPV status. Future studies utilizing a larger patient population may aid in elucidating statistically significant clinical associations in our local population
human papillomavirus ; oropharyngeal cancer ; p16