title: Duodenal gangliocytic paraganglioma presenting as an ampullary tumor.
abstract: CONCLUSIONS
  We report a case of a duodenal gangliocytic paraganglioma that had an unusual clinical presentation and atypical immunohistochemical features.
  
  
  BACKGROUND
  Duodenal gangliocytic paragangliomas are rare tumors of the gastrointestinal tract with approx 70 cases reported in the literature. The most common presentation is with gastrointestinal bleeding, whereas obstructive jaundice is very uncommon. Immunohistochemistry typically shows positive epithelial cell staining for somatostatin, pancreatic polypeptide, and other neuroendocrine markers.
  
  
  METHODS
  A 56-yr-old man presented with intermittent episodes of epigastric pain, vomiting, and obstructive jaundice. Upper gastrointestinal endoscopy revealed a pedunculated ampullary tumor that was subsequently confirmed by computed tomography. At operation, there was marked secondary obstructive chronic pancreatitis in the remaining pancreas necessitating a pylorus-preserving total pancreatectomy.
  
  
  RESULTS
  Histology confirmed typical features of a duodenal gangliocytic paraganglioma, but immunohistochemistry demonstrated negative staining for somatostatin and other polypeptides, which is in contrast to most other reported cases. Two years after surgery, the patient remains alive and well on medical treatment with no evidence of recurrent tumor.
authors.affiliation: Department of Surgery, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: Evans
authors.forename: P G
authors.initials: PG
authors.lastname: Wilson
authors.forename: P C
authors.initials: PC
authors.lastname: Barber
authors.forename: J P
authors.initials: JP
authors.lastname: Neoptolemos
mesh_terms: D014670:Ampulla of Vater / Q000473:pathology; D003138:Common Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D004379:Duodenal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016900:Neurofilament Proteins / Q000032:analysis; D010235:Paraganglioma / Q000175:diagnosis* / Q000473:pathology; D009418:S100 Proteins / Q000032:analysis
chemical_list: D016900:Neurofilament Proteins; D009418:S100 Proteins