title: Nonfunctioning cystic neuroendocrine neoplasms of the pancreas.
abstract: BACKGROUND
  Three types (functioning solid, nonfunctioning solid, and functioning cystic) of neuroendocrine neoplasms (benign and malignant) of the pancreas have been reported.
  
  
  METHODS
  We report three patients with nonfunctioning neuroendocrine neoplasms of the pancreas with cystic components, a type of neoplasm not previously reported. One of the neoplasms we report was benign; the other two were malignant. The patients were admitted with abdominal pain. In each case an abdominal computed tomography scan defined a large multicystic pancreatic mass.
  
  
  RESULTS
  In all instances, immunochemical staining was positive for neuroendocrine markers, confirming the neuroendocrine nature of the tumors. The nonfunctional nature of the neoplasms was confirmed by (1) the absence of clinical symptoms traditionally attributed to neuroendocrine secretagogues and (2) the lack of gastroenteropancreatic peptide serum levels.
  
  
  CONCLUSIONS
  Two of these three cases represent another subset of pancreatic neuroendocrine pathology: a nonfunctional cystic neoplasm. Increased clinical awareness, appropriate operation, and better immunohistochemical staining techniques may yield more, heretofore unrecognized, subtypes. These cases reemphasize the need for proper surgical exploration and biopsy of all unexplained pancreatic cystic lesions, particularly if they are multicystic.
authors.affiliation: Department of Surgery, University of Kentucky Chandler Medical Center, Lexington.
authors.forename: R W
authors.initials: RW
authors.lastname: Schwartz
authors.forename: N A
authors.initials: NA
authors.lastname: Munfakh
authors.forename: T N
authors.initials: TN
authors.lastname: Zweng
authors.forename: W E
authors.initials: WE
authors.lastname: Strodel
authors.forename: E
authors.initials: E
authors.lastname: Lee
authors.forename: N W
authors.initials: NW
authors.lastname: Thompson
mesh_terms: D007516:Adenoma, Islet Cell / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D010181:Pancreatic Cyst / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery