Comparison of Patient- and Clinician-Collected Anal Cytology Samples to Screen for Human Papillomavirus–Associated Anal Intraepithelial Neoplasia in Men Who Have Sex with Men

is increasing in prevalence and is more common among men who have sex with men and HIV-positive individuals than cervical cancer is among women in the United States. Cytology screening can detect the anal cancer precursor, anal intraepithelial neoplasia (AIN). Little is known about self-collected samples for AIN screening, and few community-based AIN estimates exist. Objective: To compare the sensitivity of self-collected versus clinician-collected anal cytology specimens to detect biopsy-confirmed AIN and the prevalence estimate of AIN in a community sample. Design: Cross-sectional study. Participants were mailed anal cytol-ogy self-collection kits with instructions. Clinicians repeated anal cytology and performed high-resolution anoscopy with biopsies as the diagnostic reference standard. Setting: San Francisco, California. Patients: Community-based sample of men who have sex with men. Measurements: Prevalence of anal HPV and AIN. Sensitivity and specificity of self-collected and clinician-collected anal cytology specimens to diagnose AIN were calculated. Results: Biopsy-proven AIN was diagnosed in 57 % of HIV-positive and 35 % of HIV-negative participants (P 0.04), and 80 % pro-vided adequate self-collected specimens for interpretation. The sen-sitivity of cytology to detect AIN in HIV-positive men was 75