B-307 Anatomical Distribution and Risk Classification of Human Papillomavirus: A Six-year laboratory-Based Study (2020-2025)

Abstract

Human Papillomavirus (HPV) comprises a heterogeneous group of DNA viruses and represents one of the most prevalent sexually transmitted infections (STI) worldwide, with significant involvement of the genital and oropharyngeal regions. Globally, an estimated 620,000 cancer cases in women and 70,000 cases in men were attributable to HPV in 2019. In Brazil, cervical cancer is the third most frequent malignancy, with high-risk genotypes 16 and 18 accounting for 70% of cases worldwide. This study aimed to evaluate the distribution of oncogenic high-risk HPV genotypes according to anatomical site in a specific population over a six-year period. A retrospective analysis was conducted using the database of a Brazilian laboratory between January 2020 and December 2025, including clinical samples from patients suspected of HPV infection. The methodology applied was real-time PCR genotyping using a qualitative commercial assay performed on the Cobas® 4800 system. The analysis included the identification of high-risk HPV types: (i) HPV-16, (ii) HPV-18, and (iii) other high-risk HPV types (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68). The body sites were classified into 11 regions: anal/rectal, penile, urethral, suprapubic, mid-meatus, cervicovaginal, cervix, vagina, vulva, gastrointestinal tract (GIT), and unidentified (UI). A total of 11,511 samples were analyzed during the study period, of which 2,587 (22.47%) were positive for high-risk subtypes. Over the six years, the positivity rate ranged from 18.7% to 37.5%, with 2021 representing the highest positivity rate at 37.5% (605/1,614) and 2025 representing the lowest positivity rate at 18.7% (626/3,348), a year that also presented the highest testing volume. The category classified as other high-risk HPV types was the most frequent, accounting for 77.2% (1,998/2,587), regardless of the year and anatomical site evaluated, followed by subtype HPV-16-only (10.9%), HPV-18-only (3.1%), and the combinations HPV-16+18 (0.4%), HPV-16+other (5.6%), HPV-18+other (2.4%), and HPV-16+18+other (0.5%). Regarding collection sites, the most affected region was the cervix with 39.0% (1,008/2,587) of cases, followed by the vaginal region 24.9%, cervico-vaginal region (21%), and vulva (11.6%). The other seven regions presented lower positivity rates, ranging from 0.04% to 1.7%. Subtype HPV-16 was the second most frequent in the suprapubic, cervical, and vaginal regions. For the penile, vulvar, and GIT regions, the second most frequent subtype was the combination HPV-16+others. The anal/rectal region had the second highest frequency of subtype HPV-16 (16.7%) and HPV-18+others (16.7%). The UI sites showed the second highest frequency of HPV-16 (11.1%) and the combination of HPV-16+others (11.1%). The findings demonstrate a high prevalence of HPV types classified as other high-risk HPV types, although the specific distribution of individual subtypes within this group could not be precisely determined. Brazil provides a free vaccination program using the quadrivalent HPV vaccine (subtypes 6, 11, 16, and 18); therefore, understanding the distribution of subtypes classified as other high-risk HPV types may support optimization of vaccination strategies and improve the understanding of local HPV epidemiology.