title: Hepatobiliary cystadenoma with mesenchymal stroma in a patient with chronic hepatitis C.
abstract: Hepatobiliary cystadenoma was suggested to be uncommon and it is often difficult to make a differential diagnosis. We report a case of a 65-year-old woman who presented with changes in the structure of a cyst that had been observed for the previous 10 years. Diagnostic imaging revealed a 7-cm-diameter cystic lesion with internal septations and papillary projections in her liver. All laboratory test results were normal; however, cystic fluid carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 were raised, at 160 ng/ml andover 200,000 U/ml, respectively. Owing to changes in the structure of the cyst and the difficulty of differential diagnosis from cystadenocarcinoma, a complete surgical excision was performed. The histological findings indicated that the tumor consisted of a multilocular cyst lined by glandular cells (with cuboidal or tall columnar cystoplasm), which were immunohistochemically positive for cytokeratin, CEA, epithelial membrane antigen, and CA 19-9. The underlying stroma was composed of proliferating primitive spindle cells which were immunoreactive for vimentin, alpha-smooth muscle actin, muscle-specific actin, and desmin, and resembled ovarian stroma. From these findings, this tumor was diagnosed as hepatobiliary cystadenoma with mesenchymal stroma. Even though the tumor was previously diagnosed as a simple liver cyst, it was necessary to pay special attention to the changes in the structure of the cyst, using ultra sonography and/or computed tomography, bearing in mind hepatobiliary cystadenoma with mesenchymal stroma. The malignant potential of this tumor is stressed, and complete surgical resection is the recommended therapy.
authors.affiliation: Department of Internal Medicine, Saiseikai Gotsu General Hospital, Shimane, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Maruyama
authors.forename: Chisato
authors.initials: C
authors.lastname: Hirayama
authors.forename: Satoru
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Masayuki
authors.initials: M
authors.lastname: Inoue
authors.forename: Kensuke
authors.initials: K
authors.lastname: Umeki
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Maeta
authors.forename: Ichiro
authors.initials: I
authors.lastname: Konishi
authors.forename: Kazunori
authors.initials: K
authors.lastname: Suzuki
authors.forename: Shinji
authors.initials: S
authors.lastname: Kajitani
authors.forename: Juro
authors.initials: J
authors.lastname: Abe
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kishimoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Horie
mesh_terms: D000368:Aged; D001661:Biliary Tract Neoplasms / Q000150:complications / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D003537:Cystadenoma / Q000150:complications / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D005260:Female; D006498:Hepatectomy; D019698:Hepatitis C, Chronic / Q000150:complications*; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000473:pathology; D008113:Liver Neoplasms / Q000150:complications / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D008648:Mesoderm / Q000473:pathology