Risk Factors for Cholangiocarcinoma in Khon Kaen, Thailand: A Nested Case-Control Study

The present nested case-control study within the Khon Kaen cohort study was conducted to assess riskfactors for cholangiocarcinoma (CCA) development. Cases were 108 subjects with proven CCA by ultrasoundat least and controls also numbered 108, matched by sex, age (not more than 3 years difference) and period ofrecruitment to the cohort (not more than 3 months difference). A questionnaire was constructed based on thatemployed for the Khon Kaen cohort study recruitment. McNemar’s chi-square test and conditional logisticregression were used for crude analysis and multivariables analysis. Results revealed a sex ratio of 2:1 formales:females. The current study found a statistically significant association when adjusted for other potentialcovariate factors between cholangiocarcinoma and the consumption of total fruits 1.0-2.08 times per day (OR0.32; 95%CI: 0.12-0.88) and history of Opisthorchis viverrini (OV) eggs in stools at recruitment plus consumptionof meat < 0.45 times per day (OR 2.99; 95%CI: 1.04-8.62). The findings suggest that OV infestation is thestrongest risk factor for development of cholangiocarcinoma and also suggests decrease in risk among individualswho consume more fruit.