A malignant soft tissue neoplasm that arises from the extrahepatic bile ducts. Representative examples include Kaposi sarcoma, leiomyosarcoma, and rhabdomyosarcoma. The disease is extrahepatic bile duct sarcoma (MONDO_0024658). Also known as: sarcoma of extrahepatic bile duct, sarcoma of the extrahepatic bile duct.