Implementation of a Screening Program for High-Grade Anal Dysplasia in High-Risk Patients in a Tertiary Cancer Center.

Introduction: The incidence of anal squamous cell carcinoma (SCC) has been increasing over the last decades. Human papillomavirus (HPV) infection accounts for more than 90% of anal cancers, and HIV co-infection increases the risk of invasive cancer. Men who have sex with men (MSM) with HIV are the highest risk group for developing anal high-grade squamous intraepithelial lesions (aHSILs), which can be found in 45%-50% of these patients and are precursor lesions for invasive cancer.