Anal cancer is a disease with a low but gradually increasing incidence, especially in developed countries. Most of these cancers are caused by the HPV. In Switzerland, more than 70 % of the sexually active population is infected with HPV at least once, making it the most common sexually transmitted disease. Immunosuppression and anal sex remain other major risk factors. Precancerous lesions can progress to anal cancer (up to 13 % at 5 years), hence the importance of early detection. High resolution anoscopy is the standard of care for diagnosis and primary treatment of lesions. It is therefore important to monitor at-risk groups and to proactively screen for gynaecological and anal HPV infection.