Risk factors of intrahepatic cholangiocarcinoma in patients with hepatolithiasis: a case-control study

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. CONCLUSION: Smoking, family history of cancer and duration of symptoms > 10 years may be risk factors for ICC in patients with hepatolithiasis.