Human Papillomavirus-Related Anal Precancerous Lesions in Men Who Have Sex With Men: A Comparative Study of Pre-exposure Prophylaxis Users and HIV-Positive Individuals.

BACKGROUND

Although anal cancer is rare, it disproportionately affects high-risk groups such as men who have sex with men (MSM) and people with human immunodeficiency virus (HIV). MSM using Pre-Exposure Prophylaxis (MSM-PrEP) represent an emerging subgroup with behavioral risk factors that may increase susceptibility to High-Risk Human Papillomavirus (HRHPV) infection and anal High-grade Squamous Intraepithelial Lesions (HSIL). However, data on precancerous anal lesions in this group remain unexplored.This study aims to compare the prevalence and distribution of histological abnormalities detected by High-Resolution Anoscopy (HRA) between MSM-PrEP and MSM with HIV (HIV + MSM) and to explore the association between anal HSIL and anal swab results using cytology and HRHPV testing.

METHODS

This secondary exploratory analysis extended a prospective, monocentric cross-sectional study on cytology and HPV infection conducted at the HIV Reference Centre and PrEP Clinic of Universitair Ziekenhuis Brussel by incorporating histological data.

RESULTS

A total of 85 MSM-PrEP and 93 HIV + MSM underwent HRA. Histologically confirmed anal HSIL did not differ significantly between MSM-PrEP and HIV + MSM (OR 0.6, 95% CI .32-1.25). No significant variation was observed in the overall histological outcome distribution (P = .401). A history of gonorrhea was significantly associated with HSIL (OR 2.39, 95% CI 1.03-5.55). Cytology showed limited discriminatory value, while HRHPV infection was present in all HSIL cases. Many lesions were linked to HRHPV types other than HPV16.

CONCLUSIONS

MSM-PrEP may be at similarly high risk for anal HSIL as HIV + MSM, underscoring the need for tailored screening strategies.