title: Solitary true cyst of the pancreas in an adult: report of a case.
abstract: BACKGROUND
  Solitary true cyst of the pancreas is rare in adults, and the differential diagnosis of cystic lesions of the pancreas is challenging.
  
  
  OBJECTIVE
  To describe a solitary true cyst of the pancreas in an adult and discuss the differential diagnosis.
  
  
  METHODS
  A 50 yr old woman presented with a mass lesion in the right upper quadrant of the abdomen. Abdominal computed tomography showed a cystic lesion, with a maximum diameter of 12 cm, between the inferior surface of the liver and the ascending colon. The cyst was homogenous and had smooth edges. On magnetic resonance imaging, a unilocular cyst was seen that was low intensity on T1-weighted images and very high intensity on T2-weighted images. No connection between the cyst and the pancreatic ductal system was demonstrated on endoscopic retrograde cholangiopancreatography. Laparotomy was performed with a presumptive diagnosis of cystic tumor of the pancreas.
  
  
  RESULTS
  On pathologic examination, the cyst was serous and was lined with a single layer of normal cuboidal epithelium that was periodic acid Schiff stain negative. Meticulous examination failed to identify honeycomb-like microcysts characteristic of serous cystadenoma. The final diagnosis was a solitary true cyst of the pancreas.
  
  
  CONCLUSIONS
  The differential diagnosis of solitary true cyst from other cystic lesion of the pancreas usually is based on histology. Particular care must be taken to distinguish this lesion from macrocystic serous cystadenoma.
authors.affiliation: Department of Surgical Oncology, Division of Cancer Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan. osamu480111@nifty.com
authors.forename: O
authors.initials: O
authors.lastname: Takahashi
authors.forename: S
authors.initials: S
authors.lastname: Kondo
authors.forename: S
authors.initials: S
authors.lastname: Hirano
authors.forename: Y
authors.initials: Y
authors.lastname: Ambo
authors.forename: E
authors.initials: E
authors.lastname: Tanaka
authors.forename: T
authors.initials: T
authors.lastname: Morikawa
authors.forename: S
authors.initials: S
authors.lastname: Okushiba
authors.forename: H
authors.initials: H
authors.lastname: Kato
mesh_terms: D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D010181:Pancreatic Cyst / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed