title: Hepatoid adenocarcinoma of the gallbladder: Case report and review of the literature.
abstract: A rare case of hepatoid adenocarcinoma (HAC) of the gallbladder occurred in a 72-year-old man who presented with abdominal pain and was admitted to hospital. Ultrasonography and computed tomography revealed a mass in the gallbladder, multiple nodules in the liver and enlargement of the lymph nodes. He was diagnosed as having a gallbladder carcinoma with multiple liver and lymph node metastases. Cholecystectomy and partial hepatectomy was performed. Histologically, most of the mass in the gallbladder was composed of cells with eosinophilic cyto-plasm arranged in a trabecular pattern, which resembled hepatocellular carcinoma, but there was a component of well-differentiated adenocarcinoma in the mucosa. Immunohistochemically these hepatoid tumor cells were positive for Hepatocyte (Hepatocyte Paraffin 1: Hep Par1), which is considered highly sensitive and highly specific for hepatocyte differentiation. Based on these findings, this case was diagnosed as hepatoid adenocarcinoma of the gallbladder, which is generally a vary rare neoplasm in the literature, but should be included in the differential diagnosis of a mass in the gallbladder.
authors.affiliation: Department of Pathology, Tohoku University Hospital, Sendai, Japan. ksakamoto@patholo2.med.tohoku.ac.jp
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sakamoto
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Monobe
authors.forename: Masato
authors.initials: M
authors.lastname: Kouno
authors.forename: Takuya
authors.initials: T
authors.lastname: Moriya
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sasano
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D017809:Fatal Outcome; D005706:Gallbladder Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D006498:Hepatectomy; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008297:Male
chemical_list: D014408:Biomarkers, Tumor