BACKGROUND: The incidence of anal cancer among HIV-infected patients is higher than that in other populations. Anal high-grade squamous intraepithelial lesions are considered precursors to invasive squamous-cell carcinomas and are strongly associated to high-risk human papillomavirus infection.
OBJECTIVE: The aim of this study is to determine the prevalence of anal high-grade squamous intraepithelial lesions through screening based on cytology and high-resolution anoscopy with biopsy in a cohort of HIV-infected men who have sex with men.
DESIGN: This investigation is an observational cross-sectional cohort study.
SETTING: The study was conducted in the HIV unit of a tertiary hospital in Spain.
PATIENTS: Three hundred HIV-infected men who have sex with men participated. Physical examination led to a diagnosis of perianal squamous-cell carcinoma and high-grade squamous intraepithelial lesions in 2 patients who were then excluded.
INTERVENTIONS: Anal liquid cytology was performed. Patients with cytological abnormalities underwent high-resolution anoscopy and biopsy.
MAIN OUTCOME MEASURE: The primary outcome measured was biopsy-proven high-grade squamous intraepithelial lesions.
RESULTS: The median age was 41 ± 10.5 years. The mean and nadir CD4 cell counts were 651 ± 205 cells/mm3 (interquartile range, 438–800) and 273 ± 205 cells/mm3 (interquartile range, 131–362). High-risk human papillomavirus was detected in 80.9% of patients, and human papillomavirus 16 was detected in 35.9% of patients. The mean number of human papillomavirus genotypes was 4.6 ± 2.9 (CI, 2–6). Anal cytology was abnormal in 40.9% of patients (n = 122/298; interquartile range, 35.4%–46.6%). High-resolution anoscopy and biopsies were performed in 119 patients. The results of histological analyses were as follows: normal, 7.7% (n = 23); condyloma, 4.3% (n = 13); anal intraepithelial neoplasia 1, 5.7% (n = 17); anal intraepithelial neoplasia 2, 14% (n = 42); and anal intraepithelial neoplasia 3, 8% (n = 24). The overall prevalence of high-grade squamous intraepithelial lesions among patients with abnormal cytology was 54% (95% CI, 45.1%–62.8%). A diagnosis of high-grade squamous intraepithelial lesions was associated with human papillomavirus 16 and human papillomavirus 51 infection, and with detection of a higher number of human papillomavirus genotypes.
LIMITATIONS: High-resolution anoscopy was only performed in patients with abnormal cytology.
CONCLUSIONS: The prevalence of high-risk human papillomavirus infection and high-grade squamous intraepithelial lesions is high in our cohort. Physical examination enabled straightforward diagnosis of perianal high-grade squamous intraepithelial lesions and squamous-cell carcinoma in 2 patients.