title: Electron microscopic and immunoelectron microscopic demonstration of pancreatic polypeptide cells in glucagonoma: colocalization of pancreatic peptide and glucagon in single secretory granules.
abstract: We describe a case of pancreatic tumor in a 65-year-old woman with typical glucagonoma syndrome. Plasma glucagon (GL) and pancreatic polypeptide (PP) were markedly elevated up to 1404 and 1200 pg/ml, respectively. Histologic examination of the metastatic tumors in liver and lymph nodes showed endocrine-type tumors composed of GL-positive cells some of which coexpressed PP immunoreactivity. Electron microscopy revealed the tumor cells with single-type secretory granules similar to normal A cell granules. Double immunogold staining demonstrated both GL and PP immunoreactivities in the same secretory granules. Biologic and diagnostic significance of coexpression of PP and GL in a single secretory granules of pancreatic endocrine tumors is discussed briefly.
authors.affiliation: Department of Surgery, Cancer Research Institute Hospital, Kanazawa University, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ooi
authors.forename: S
authors.initials: S
authors.lastname: Katsuda
authors.forename: I
authors.initials: I
authors.lastname: Nakanishi
authors.forename: T
authors.initials: T
authors.lastname: Kameya
authors.forename: K
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: H
authors.initials: H
authors.lastname: Kitamura
authors.forename: Y
authors.initials: Y
authors.lastname: Hayakawa
mesh_terms: D007516:Adenoma, Islet Cell / Q000473:pathology*; D000368:Aged; D003594:Cytoplasmic Granules / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D005934:Glucagon / Q000276:immunology / Q000378:metabolism*; D005935:Glucagonoma / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D008854:Microscopy, Electron / Q000379:methods; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D010191:Pancreatic Polypeptide / Q000276:immunology / Q000378:metabolism*
chemical_list: D010191:Pancreatic Polypeptide; D005934:Glucagon