title: Early cystic duct carcinoma of new classification.
abstract: BACKGROUND
  Classically defined cystic duct carcinoma is extremely rare owing to its strict diagnostic criteria, which are not suitable in actual clinical settings. Recently, several new classifications of cystic duct carcinoma were reported, which defined it as a tumor with its center located in the cystic duct. On the other hand, the incidence of cystic duct carcinoma, based on the new classifications, is not rare, but all reported cases are advanced.
  
  
  METHODS
  A 77-year-old man with dilatation of the common bile duct, a stricture at the level of the cystic duct junction, and a filling defect of contrast medium into cystic duct in endoscopic retrograde cholangiopancreatography was diagnosed with cystic duct carcinoma. Radical cholecystectomy with bile duct resection was performed. In the resected specimen, we found that a 2 cm tumor whose center was located in the cystic duct and vertically limited to the mucosal layer. Horizontally, the tumor was superficially spread in the gallbladder, which were also limited to the mucosal layer.
  
  
  CONCLUSIONS
  Here we report a first case of early cystic duct carcinoma diagnosed according to a new classification that had spread superficially into the gallbladder. When treating an early cystic duct carcinoma, it is important to note that even localized carcinoma can potentially invade into adjacent organs or metastasize to regional lymph nodes due to the location of cystic duct.
  
  
  CONCLUSIONS
  It is suggested that perform radical resection such as cholecystectomy with gallbladder fossa resection, extrahepatic bile duct resection and regional lymphadenectomy is the treatment of choice.
authors.affiliation: Department of Digestive Surgery, Hepato Pancreato Billiary Surgery Unit, Toranomon Hospital, Tokyo, Japan.
authors.forename: Kazunari
authors.initials: K
authors.lastname: Sasaki
authors.forename: Masamichi
authors.initials: M
authors.lastname: Matsuda
authors.forename: Masaji
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Harano
authors.forename: Takeshi
authors.initials: T
authors.lastname: Fujii
authors.forename: Goro
authors.initials: G
authors.lastname: Watanabe
references.citation: World J Surg. 2007 Jan;31(1):155-61; discussion 162-3
references.pmid: 17180477
references.citation: Surg Today. 2009;39(9):770-9
references.pmid: 19779773
references.citation: J Hepatobiliary Pancreat Surg. 2009;16(1):75-82
references.pmid: 19096752
references.citation: J Surg Oncol. 1991 Dec;48(4):282-6
references.pmid: 1745055
references.citation: Br J Surg. 1951 Sep;39(154):183-5
references.pmid: 14886607
references.citation: J Hepatobiliary Pancreat Surg. 2001;8(6):505-10
references.pmid: 11956900
references.citation: World J Surg. 2008 Apr;32(4):621-6
references.pmid: 18224484