The changing picture of high-grade anal intraepithelial neoplasia in men who have sex with men: The effects of 10 years of experience performing high-resolution anoscopy

BACKGROUND: Ten years ago, we published findings from anal dysplasia screening in a metropolitan surgical practice where the majority of men who have sex with men had biopsy-proven high-grade anal intraepithelial neoplasia. OBJECTIVE: This study aimed to determine the effect of 10 years of experience in anal dysplasia screening on the prevalence of high-grade anal intraepithelial neoplasia. DESIGN: A retrospective chart review was performed of all anal cytology results of 1189 men who have sex with men screened in a 1-year period, with subsequent highresolution anoscopy and biopsy as necessary. PATIENTS: The patients studied were men who have sex with men. MAIN OUTCOME MEASURE: The main outcome measure was biopsy-proven high-grade anal intraepithelial neoplasia. RESULTS: There were 315 (37.2%) biopsy-verified instances of high-grade anal intraepithelial neoplasia. Regression analysis determined that age, HIV status, infection by high-risk human papillomavirus, and abnormal cytology results were significant predictors of high-grade anal intraepithelial neoplasia. In a 1-year period, the number of men who have sex with men screened was nearly 7 times greater than in the 2-year period studied 10 years earlier. LIMITATIONS: We did not separately analyze patients who had previously been treated for high-grade anal intraepithelial neoplasia. CONCLUSIONS: Severity of cytology and infection with high-risk human papillomavirus are the most significant predictors of high-grade anal intraepithelial neoplasia, underscoring the importance of anal dysplasia screening. Our ability to identify high-grade anal intraepithelial neoplasia has improved with 10 years of experience performing high-resolution anoscopy.