title: Duodenal periampullary gangliocytic paraganglioma: report of two cases with immunohistochemical and ultrastructural study.
abstract: We report two cases of Gangliocytic Paraganglioma (GP) of the ampulla of Vater occurring in a 63-year-old and a 34-year-old individual. The patients were both admitted for a long history of intermittent gastrointestinal bleeding and abdominal discomfort, with no other symptoms. At endoscopy, the GP appeared as a polypoid, ulcerated mass in the ampullar region, measuring 2.5x1.8 and 2 cm, respectively. Microscopically, the tumors showed similar features and were composed of epithelial cells (more than 50%), spindle cells, and ganglion-like cells. The epithelial cells showed clear cytoplasm and formed nests (zellballen or paraganglioma-like groups), and less frequently, cords (carcinoid-like), extending to mucosa and submucosa. Ganglion cells were sparse, constantly associated with the spindle cells. Both epithelial and ganglion cells were synaptophysin, chromogranin A, and anti-neurofilament immunoreactive. The spindle cells were all S-100 positive. Ultrastructural studies revealed dark and light cells, rare elongated cellular processes, secretory granules, and fine fibrils resembling neurofilaments. The histogenesis of GP is still a matter of debate, however its neoplastic nature is supported by the occasionally reported malignant evolution.
authors.affiliation: Institute of Pathological Anatomy and Histology, University of Padova, Italy. altavill@ux1.unipd.it
authors.forename: G
authors.initials: G
authors.lastname: Altavilla
authors.forename: S
authors.initials: S
authors.lastname: Chiarelli
authors.forename: A
authors.initials: A
authors.lastname: Fassina
mesh_terms: D000328:Adult; D053379:Chromogranin A; D002864:Chromogranins / Q000032:analysis; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004386:Duodenum; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000473:pathology; D007414:Intestinal Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000648:ultrastructure; D008247:Lysosomes / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D008928:Mitochondria / Q000648:ultrastructure; D009454:Neurofibrils / Q000648:ultrastructure; D010235:Paraganglioma / Q000737:chemistry / Q000175:diagnosis* / Q000648:ultrastructure; D009418:S100 Proteins / Q000032:analysis; D016708:Synaptophysin / Q000032:analysis
chemical_list: D053379:Chromogranin A; D002864:Chromogranins; D009418:S100 Proteins; D016708:Synaptophysin