title: Risk factors of intrahepatic cholangiocarcinoma in patients with hepatolithiasis: a case-control study.
abstract: BACKGROUND
  Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown. We carried out a hospital-based case-control study to identify risk factors for the development of ICC in patients with hepatolithiasis in China.
  
  
  METHODS
  Eighty-seven patients with pathologically diagnosed hepatolithiasis associated with ICC and 228 with hepatolithiasis alone matched by sex, age (+/-2 years), hospital admittance and place of residence were interviewed during the period of 2000-2008. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each risk factor.
  
  
  RESULTS
  Among the patients with hepatolithiasis associated with ICC, the mean age was 57.7 years and 61.0% were female. Univariate analysis showed that the significant risk factors for ICC development in hepatolithiasis were smoking, family history of cancer, appendectomy during childhood (under age 20), and duration of symptoms >10 years. In multivariate stepwise logistic regression analysis, smoking (OR=1.931, 95% CI: 1.000-3.731), family history of cancer (OR=5.175, 95% CI: 1.216-22.022), and duration of symptoms >10 years (OR=2.348, 95% CI: 1.394-3.952) were independent factors.
  
  
  CONCLUSIONS
  Smoking, family history of cancer and duration of symptoms >10 years may be risk factors for ICC in patients with hepatolithiasis.
authors.affiliation: Molecular Oncology Laboratory, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438, China.
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Liu
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Zhou
authors.forename: Le-Hua
authors.initials: LH
authors.lastname: Shi
authors.forename: Zheng-Feng
authors.initials: ZF
authors.lastname: Yin
mesh_terms: D000428:Alcohol Drinking / Q000009:adverse effects*; D001650:Bile Duct Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D001653:Bile Ducts, Intrahepatic; D002681:China / Q000453:epidemiology; D018281:Cholangiocarcinoma / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020347:Lithiasis / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D008099:Liver; D008113:Liver Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*