title: The risk of carcinogenesis in congenital choledochal cyst patients: an analysis of 214 cases.
abstract: BACKGROUND
  Choledochal cysts are most common in Asian populations. In addition, the incidence of biliary tract malignancies from choledochal cysts is increasing, but the risk of carcinogenesis is still unclear.
  
  
  METHODS
  Clinical data from 214 congenital choledochal cyst cases from 1968 to 2013 were retrospectively analyzed.
  
  
  RESULTS
  Todani type I was more common (139, 65.0%) than type IVa (53, 24.8%) or type V (17, 7.9%) in these choledochal cyst patients. Biliary tract malignant tumors occurred in the gallbladder (2, 13.3%), common bile duct (10, 66.7%), and intrahepatic bile duct (3, 20%) in 15 patients (7.0%), including one patient in whom malignant transformation occurred in the intrahepatic bile duct in a type IVa patient 15 years after extrahepatic cyst resection. An age at symptom onset ≥ 60 years was a risk factor (p < 0.001), while an initial complete surgery was a protective factor for carcinogenesis (p = 0.001).
  
  
  CONCLUSIONS
  Choledochal cysts should be removed once diagnosed because of an increased risk of malignant transformation with increasing age. Complete cyst removal is necessary for the first surgical treatment. Additional hepatectomy should be considered for type IVa choledochal cysts because cholangiocarcinoma can arise from the intrahepatic bile duct years after the extrahepatic cyst excision.
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: He
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China; Peking University Wu-Jieping Urology Center, Peking University Shougang Hospital, Peking University Health Science Center, Beijing, 100144, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Qu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
authors.forename: Bing-Lu
authors.initials: BL
authors.lastname: Li
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Hong
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology*; D002288:Adenocarcinoma, Mucinous / Q000453:epidemiology; D000328:Adult; D017668:Age of Onset; D000368:Aged; D001650:Bile Duct Neoplasms / Q000453:epidemiology; D001653:Bile Ducts, Intrahepatic; D063646:Carcinogenesis; D018281:Cholangiocarcinoma / Q000453:epidemiology; D015529:Choledochal Cyst / Q000453:epidemiology* / Q000601:surgery; D015331:Cohort Studies; D003138:Common Bile Duct Neoplasms / Q000453:epidemiology*; D003536:Cystadenocarcinoma / Q000453:epidemiology; D005260:Female; D005706:Gallbladder Neoplasms / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors