Abstract 446P
Background
Head and neck cancer is one of the most common cancers in India. The incidence of HPV related OPSCC is showing a rising trend in the age group of 40-45 years.The study in prevalence and outcome of HPV related oropharyngeal squamous cell carcinoma (OPSCC) is sparse .In this study we aim to identify the frequency of HPV infection in OPSCC cancer patients,assess treatment response and survival about HPV positivity and its correlation to P16 expression.
Methods
The study sample consists of 100 paraffin-embedded tissue blocks during the period from January 2010 to December 2012. Follow-up information on disease status were collected till May 2023.The multiplex PCR was used to amplify the targeted sequences using HPV type-specific primers. The presence of HPV DNA was taken as HPV positive. p16 expression was tested by IHC. The staining was scored: negative (<10% positive), mild (<20% positive), moderate (20-50% positive) and intense (>50% of positive). Moderate and intense staining is grouped as positive expression.
Results
A total of 98 patients. The median age was 58 years. There were 90 males and 8 females. Out of 98 samples,47 tested positive for P16, 48 were negative. Among the 98 patients, HPV DNA were available for 82 patients. HPV DNA positivity was reported in 25 patients and 57 were negative. Among the 25 HPV positive, 16 were HPV 16 positive, 14 tested positive for HPV 18 and 5 were both positive. The median follow-up was 134 months. The median survival was 48 months and median time to recurrence was 17.2 months. The 5-year OS was 42.6% and 51.2% respectively for p16 negative and p16 positive tumors (p=0.689). The 5-year DFS were 49.0%, in p16 negative and 51.9% in p16 positive (p=0.959). Survival analysis was done based on HPV DNA status (both 16 and 18 subtypes together) as well. Analysis based on HPV 16 DNA alone showed 10 years OS of 31.9% for HPV 16 negative versus 54.2% for HPV 16 positive tumors (p=0.0309).
Conclusions
This study demonstrated a P16 positivity rate of 49.47% and HPV DNA positivity rate of 30.37%. No significant correlation was observed between p16 expression and HPV status. Double positivity (P16 and HPV positive) was associated with better OS and DFS.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.