Fig. 2

Cumulative risk of anal HSIL and cancer every 4 years (0–4, 5–8, 9–12, 13–16 years) since patient initial clinical visit dates. The current cohort began in 1999 and ended in early 2018. The last period (17–20 years) was excluded due to an incomplete 4-year follow-up. Diagnoses of anal HSIL declined while cancer cases increased during the follow-up