Risk Factors for Cholangiocarcinoma in the Lower Part of Northeast Thailand: a Hospital-based Case-control Study

Background: Cholangiocarcinoma (CCA) is the most common cancer in Northeast Thailand. It is also a crucial health problem for Thai people. Various risk factors for CCA have been identified in the upper part of Northeast Thailand, but no similar studies of risk factors have been conducted in the lower parts of the region. This study aimed to investigate factors associated with CCA in the resident population. Materials and Methods: A hospital-based case-control study was conducted during 2009-2012 with the recruitment of 123 CCA cases and 123 non-CCA patient controls, matched for sex, age and residential area. Information was collected by interview with a structured questionnaire. Blood samples were collected for assays of anti-OV antibodies. Associations between various personal factors, dietary habits, family history, the presence of anti-OV antibodies and CCA were analyzed using multiple conditional logistic regression. Results: Patients who consumed raw meat (beef, pork) and alcoholic beverages ${\geq}3$ times per week had a higher risk of CCA than non-consumers ($OR_{adj}$=4.33; 95%CI=1.14-16.35 and $OR_{adj}$=2.13; 95%CI=1.00-4.55, respectively). Patients who had a family history of cancer had a higher risk than those who did not ($OR_{adj}$=4.34; 95%CI=1.80-10.43). Also, patients who had anti-OV antibodies (AU>23.337) had a higher risk than those whose anti-OV antibodies were below the cut-off ($AU{\leq}23.34$) ($OR_{adj}$=3.09; 95%CI=1.04-9.16). Conclusions: As is the case in the upper part of Northeast Thailand, OV infection is a crucial risk factor for CCA in people who live in lower part of the region. Similarly, a family history of cancer and the consumption of alcohol are risk factors for CCA.