title: Malignant mediastinal germ cell tumor with pure hepatoid differentiation.
abstract: We describe a germ cell tumor of anterior mediastinal origin, with pure hepatoid differentiation and elevated serum AFP in a 41-year-old man. This is the first report of such a neoplasm analyzed by conventional stains and immunohistochemistry. Hepatocellular differentiation was proved by immunoreactivity with HepPar-1 and alpha-fetoproein (AFP), membranous expression of carcinoembryonic antigen (CEA-poly) in a canalicuar pattern, and focal expression of cytokeratin 19 in abortive ductular structures. Our investigation shows that mediastinal germ cell tumors with hepatoid components typically arise in middle-aged men; they are of pure hepatoid differentiation, as demonstrated here, or exclusively associated with yolk sac structures.
authors.affiliation: Department of Pathology, University of Bonn, Sigmund-Freud-Str. 25, 533127 Bonn, Germany. theuerkauf@mailer.meb.uni-bonn.de
authors.forename: Ingo
authors.initials: I
authors.lastname: Theuerkauf
authors.forename: Cristoph
authors.initials: C
authors.lastname: Axmann
authors.forename: Martin
authors.initials: M
authors.lastname: Wolff
authors.forename: Klaus
authors.initials: K
authors.lastname: Tschubel
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Fischer
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D003937:Diagnosis, Differential; D018237:Germinoma / Q000097:blood / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008479:Mediastinal Neoplasms / Q000097:blood / Q000378:metabolism / Q000473:pathology*; D000509:alpha-Fetoproteins / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D000509:alpha-Fetoproteins