title: Composite small cell and mucinous carcinoma originating from the intrahepatic bile duct: report of a case.
abstract: The biliary tract is a very rare site for the occurrence of extrapulmonary small cell carcinoma. A 68-year-old Japanese female was being followed up for autoimmune hepatitis, and was referred to our hospital because segmental intrahepatic bile duct dilation was found on routine imaging studies, suggesting intrahepatic cholangiocarcinoma. She underwent left lobectomy of the liver and concomitant resection of the caudate lobe. Microscopic examination of the explanted liver showed a primary composite tumor comprising small cell and mucinous carcinomas that originated in the intrahepatic bile duct. Further immunohistochemical studies, including cytokeratin-19 and chromogranin-A staining, showed the two cellular components of the tumor to have similar characteristics. The amphicrine properties indicated that the tumor had a monoclonal origin but with biphenotypic differentiation, which was responsible for the histogenesis of this tumor.
authors.affiliation: Department of Surgery, Saiseikai Fukuoka General Hospital, 1-3-46 Tenjin, Chuou-ku, Fukuoka 810-0001, Japan. tikesurg@yahoo.co.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Ikegami
authors.forename: Hiroto
authors.initials: H
authors.lastname: Kayashima
authors.forename: Noriaki
authors.initials: N
authors.lastname: Sadanaga
authors.forename: Shusuke
authors.initials: S
authors.lastname: Morizono
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nakashima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsuura
authors.forename: Ken
authors.initials: K
authors.lastname: Shirabe
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Maehara
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis*; D000368:Aged; D001650:Bile Duct Neoplasms / Q000175:diagnosis*; D001653:Bile Ducts, Intrahepatic; D018288:Carcinoma, Small Cell / Q000175:diagnosis*; D005260:Female; D006801:Humans; D018193:Neoplasms, Complex and Mixed / Q000175:diagnosis*