SEOM-GEMCAD-TTD clinical guidelines for anal cancer (2025).

Anal cancer is rare but increasingly common, currently accounting for 2% of all digestive neoplasms. Some 50% of anal cancers are diagnosed at the localized stage, 29% as locoregional disease, and 12% as metastatic disease. When clinical suspicion of anal cancer exists, histological confirmation, correct local staging with MRI and distant staging with thoraco-abdominal CT, and management by a multidisciplinary team are mandatory. Chemoradiotherapy with 5-FU and mitomycin C (MMC) is the standard of care for early and locally advanced disease, while combination chemotherapy with a platinum-containing compound and taxanes is the treatment of choice for metastatic disease.