title: Risk factors for cholangiocarcinoma in a low risk Caucasian population.
abstract: OBJECTIVE
  Little is known about the etiology of cholangiocarcinoma, apart from its association with liver fluke infestation.
  
  
  METHODS
  A case-control study was conducted in Athens and included six cholangiocarcinoma cases, 333 hepatocellular carcinoma cases and 360 controls with minor ailments or injuries. All subjects were interviewed and tested for hepatitis B and C infection. For all six cholangiocarcinomas, 97 hepatocellular carcinomas and 129 controls, sex steroids were determined in the blood.
  
  
  RESULTS
  Hepatitis B or C viruses, tobacco smoking, alcohol drinking and diabetes mellitus were not related to cholangiocarcinoma, but history of thyroid disease was. Estradiol levels were higher among cholangiocarcinoma cases than among the other two groups.
  
  
  CONCLUSIONS
  This study provides evidence that endocrine and autoimmune factors are important in the etiology of cholangiocarcinoma.
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA.
authors.forename: H
authors.initials: H
authors.lastname: Kuper
authors.forename: P
authors.initials: P
authors.lastname: Lagiou
authors.forename: L A
authors.initials: LA
authors.lastname: Mucci
authors.forename: R
authors.initials: R
authors.lastname: Tamimi
authors.forename: V
authors.initials: V
authors.lastname: Benetou
authors.forename: D
authors.initials: D
authors.lastname: Trichopoulos
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000209:etiology*; D006528:Carcinoma, Hepatocellular / Q000209:etiology; D016022:Case-Control Studies; D018281:Cholangiocarcinoma / Q000209:etiology*; D004958:Estradiol / Q000097:blood; D005260:Female; D006115:Greece; D006801:Humans; D008113:Liver Neoplasms / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012306:Risk; D044465:White People
chemical_list: D004958:Estradiol