[Update on anal dysplasia and anal cancer]

Anal dysplasia and anal cancers are predominantly caused by high-risk types of the human papillomavirus. Lesions are mostly asymptomatic and disproportionately affect high-risk populations such as people living with HIV, women with a history of vulvar (pre)cancer, and long-term immunosuppressed individuals. For these risk groups, the incidence of anal cancer is up to 100 times higher, which is why screening is recommended in the S2k guideline completed in 2024. However, it should be noted that two-thirds of anal cancers occur in older women without HIV, for whom scalable screening strategies do not yet exist due to a lack of feasible triaging methods. The ANCHOR study provided crucial evidence that timely diagnosis and treatment of high-grade anal dysplasia can significantly reduce the risk of anal cancer. To diagnose anal dysplasia, the German-Austrian guidelines recommend a two-stage process: after initial triaging using medical history, cytology, and HPV typing, high-resolution anoscopy (HRA) with biopsy represents the gold standard for diagnosis. Therapeutically, destructive methods (such as electrocautery or trichloroacetic acid) and local immunomodulatory therapies (imiquimod) are used. Cure rates after a single treatment session are relatively low at 10-30%; multiple treatment cycles are often necessary to clear high-grade anal dysplasia. Combining different therapeutic modalities is frequently a feasible strategy. For advanced anal cancer, recent studies such as POD1UM-303/InterAACT‑2 (immunotherapy with retifanlimab), as well as procedures like plasma HPV-ctDNA measurement (liquid biopsy) and dose-escalated/sparing radiation therapy, show promising results and give a perspective for the ongoing revision of the S3 guideline on anal cancer.