title: Population-based study of cancer risk and relative survival following sphincterotomy for stones in the common bile duct.
abstract: BACKGROUND
  Endoscopic sphincterotomy was introduced in 1974 as a procedure for removing stones in the common bile duct. To assess the long-term risk of cancer and relative survival, all patients who underwent this procedure at six different hospitals between 1977 and 1985 were identified.
  
  
  METHODS
  A total of 992 patients was identified and they were followed by linkage to the Swedish Death Registry and the Swedish Cancer Registry.
  
  
  RESULTS
  At 1 year or more after sphincterotomy there was no increased risk of cancer in the liver, gallbladder, bile duct or pancreas (standardized incidence ratio 0.80, 95 per cent confidence interval 0.3-1.9). Relative survival was lowered slightly in the first year after sphincterotomy, but did not differ from that of the background population thereafter.
  
  
  CONCLUSIONS
  Endoscopic sphincterotomy for stones in the common bile duct does not appear to affect the risk of cancer in the pancreas, liver or bile ducts, nor does it affect long-term survival.
authors.affiliation: Department of Surgery, University Hospital, Uppsala, Sweden.
authors.forename: B M
authors.initials: BM
authors.lastname: Karlson
authors.forename: A
authors.initials: A
authors.lastname: Ekbom
authors.forename: D
authors.initials: D
authors.lastname: Arvidsson
authors.forename: J
authors.initials: J
authors.lastname: Yuen
authors.forename: U B
authors.initials: UB
authors.lastname: Krusemo
mesh_terms: D000328:Adult; D000368:Aged; D002760:Cholangiopancreatography, Endoscopic Retrograde; D015331:Cohort Studies; D004067:Digestive System Neoplasms / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D042882:Gallstones / Q000601:surgery*; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000453:epidemiology; D012307:Risk Factors; D016717:Sphincterotomy, Endoscopic; D016019:Survival Analysis; D015996:Survival Rate; D016896:Treatment Outcome