BackgroundHigh-grade anal intraepithelial squamous lesion is significantly prevalent among men who have sex with men and are infected with the human immunodeficiency virus (HIV). This condition—the precursor to anal cancer—significantly increases the risk of developing it. Conversely, low-grade anal intraepithelial squamous typically follow a benign course and usually regress spontaneously. Materials and methodsTo describe a population of men who have sex with men living with HIV followed in a specialized anal cancer screening unit we conducted an observational, retrospective, and single-center study. ResultsNinety-four patients were analyzed, with a mean age of 39±9 years, and a 87% positivity rate for high-risk human papillomavirus (HR-HPV). At the initial visit, 47% presented with low-grade squamous intraepithelial lesions. The progression rate to high-grade squamous intraepithelial lesion was 37.2 per 100,000 patients/year. None of the patients developed anal cancer. Tobacco and alcohol consumption were associated with this progression. DiscussionIn this series, longer duration of HIV infection, tobacco and alcohol use and the presence of HR-HPV were significantly associated with the occurrence of high-grade intraepithelial lesions. A lower risk of progression was seen in patients with higher education. ConclusionIn men who have sex with men living with HIV, the association of factors such as smoking, alcohol, the presence of HR-HPV and an increased burden of human papillomavirus disease makes these patients more susceptible to develop high-grade anal squamous lesions.