[A Case Report of Brain Metastasis from Anal Canal Carcinoma].

A 55-year-old female with adenocarcinoma of anal canal(stage IV with lung, bone, and lymph node metastasis)underwent total pelvic exenteration surgery and chemotherapy. Chemotherapy was continued after the surgery. One month later, she presented to the emergency room with gait disorder and cognitive dysfunction. CT and MRI demonstrated metastatic brain tumor in the right cerebellar hemisphere. Craniotomy and CyberKnife surgery were performed. Histological examination revealed adenocarcinoma with atypical cells forming a papillary arrangement. She died 35 weeks after the surgery. Brain metastasis from anal carcinoma is very rare, but recent advances in chemotherapy are achieving favorable results of long-term survival, and this is likely to increase in the future. Early detection, early treatment, and combined therapy may improve the long-term outcome for patients.