Abstract 4804: Prevalence of anal HPV infection in women attending a gynecology and colposcopy clinic: Assessing the potential impact of HPV vaccination

Abstract Human papillomavirus (HPV) accounts for over 80% of anal cancer cases. In the effort to prevent HPV-related cancers, the 9-valent HPV vaccine emerged as a crucial intervention, targeting HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58; the previous 4-valent (types 6, 11, 16, 18) and 2-valent (types 16, 18). This study involved 213 women aged 21-50 attending gynecology and colonoscopy clinics in San Juan, Puerto Rico. The study assessed anal HPV prevalence and analyzed vaccination status-related differences. Anal swabs were collected for HPV testing using the ATILA AmpFire, targeting 17 HPV types. This method identified 15 high-risk HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, and 68) and two low-risk HPV types (6 and 11). Prevalence of any HPV, HR-HPV, and LR-HPV, and of specific HPV types were calculated by overall and vaccination status. Differences were assessed for statistical significance (p0. 05) using Fisher's exact or Pearson χ2 test. The mean age of women was 36. 0 ± 5. 9 years. Overall, 19. 7% (n=44) had received the HPV vaccine; among them, 52. 2% (n=23) had received the 4-valent vaccine, 2. 3% had received the 2-valent vaccine, 2. 3% had received the 9-valent vaccine, and 43. 2% were uncertain about their specific HPV vaccine type. The prevalence of anal HPV infection was 68. 5% for any HPV, 61. 5% for HR-HPV, and 15. 0% for LR-HPV. The most prevalent HR-HPV types were HPV 56 (13. 2%), HPV 68 (11. 7%), and HPV 66 (11. 2%). There were no statistically significant differences in the prevalence of any HPV, HR-HPV, and LR-HPV between vaccinated and unvaccinated women. The most common HR-HPV type among vaccinated were HPV 66 (20. 5%), HPV 31 (18. 2%), HPV 56 (15. 9%), while the most common among unvaccinated women were HPV 56 (12. 4%), HPV 68 (12. 4%), and HPV 16 (12. 4%). Additionally, when evaluating as a grouped variable, the HPV genotypes covered by the 4-valent, unvaccinated women had a significantly higher prevalence of these types as compared to those vaccinated (28. 9% vs. 13. 6%, respectively, p-value =. 03). The unvaccinated women showed a lower prevalence for HPV types covered by the 9-valent vaccine compared to the vaccinated cohort (43. 2% vs. 45. 5%). However, this difference was not statistically significant. We found a high prevalence of anal HPV among these women, with lower prevalence of 4-valent and 2-valent HPV types among vaccinated women, evidencing the pivotal role of HPV vaccination. Future research should assess the 9-valent vaccine's long-term effectiveness against more HPV types. Funding: Research Centers in Minority Institutions (RCMI), University of Puerto Rico (NIMHD # 2U54MD007600-36), and CAPAC Research Training Program (NCI #R25CA240120). Citation Format: Anelisse Dominicci-Maura, Ana Patricia Ortiz, Josefina Romaguera, Filipa Godoy-Vitorino. Prevalence of anal HPV infection in women attending a gynecology and colposcopy clinic: Assessing the potential impact of HPV vaccination abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 4804.