title: Pancreatic carcinoma that completely obstructs the Wirsung duct without dilatation of the main pancreatic duct.
abstract: OBJECTIVE
  Pancreatic carcinomas in which the main pancreatic duct (MPD) is completely obstructed are almost always associated with dilatation of the upstream MPD. However, some carcinomas are not associated with MPD dilatation despite complete MPD obstruction. This paradoxical phenomenon has not been well documented.
  
  
  METHODS
  The findings from endoscopic retrograde cholangiopancreatography in 207 cases of pancreatic head carcinomas were analyzed with special reference to this unique type of carcinoma. Twenty-five of the patients were found to exhibit no MPD dilatation on ultrasonography, computed tomography or magnetic resonance imaging.
  
  
  RESULTS
  Pancreatography via the major papilla showed complete obstruction of the MPD (112 patients with MPD dilatation and 6 without), stenosis (70 and 10, respectively), or no abnormal findings (0 and 9, respectively). In all six patients with complete MPD obstruction but without upstream MPD dilatation, injection of the minor papilla revealed a non-dilated dorsal pancreatic duct. The size of the obstructive carcinomas with and without MPD dilatation was comparable.
  
  
  CONCLUSIONS
  Some (3%) pancreatic head carcinomas are not associated with MPD dilatation despite complete obstruction of the Wirsung duct. In such cases, the Santorini duct drains the dorsal pancreatic duct, completely compensating for the obstructed Wirsung duct. Attention should be paid to this unique type of carcinoma in diagnosing pancreatic head carcinomas.
authors.affiliation: Department of Surgery, Kyorin University School of Medicine, Tokyo, Japan. sgym@kyorin-u.ac.jp
authors.forename: Masanori
authors.initials: M
authors.lastname: Sugiyama
authors.forename: Yumi
authors.initials: Y
authors.lastname: Izumisato
authors.forename: Nobutsugu
authors.initials: N
authors.lastname: Abe
authors.forename: Tadahiko
authors.initials: T
authors.lastname: Masaki
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Mori
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Atomi
mesh_terms: D000230:Adenocarcinoma / Q000150:complications* / Q000175:diagnosis; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003251:Constriction, Pathologic / Q000175:diagnosis / Q000209:etiology; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010183:Pancreatic Ducts; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000175:diagnosis; D012720:Severity of Illness Index