Opisthorchis viverrini (OV)-induced cholangiocarcinoma (CCA) is an important cancer in the Great Mekongregion, particularly in Thailand. Limitations of treatment options and the lack of an effective diagnostic toolfor early detection of CCA are major concerns for the control of this type of cancer. The aim of the study was toinvestigate anti-CCA activity of the ethanolic extract of Atractylodes lancea (Thunb.) DC., and the applicabilityof positron emission tomography-computed tomography (PET-CT) as a tool for detection and monitoring theprogression of CCA in Opisthorchis viverrini (OV)/dimethylnitrosamine (DMN)-induced CCA hamsters. MaleSyrian hamsters were used for toxicity tests and anti-CCA activity evaluation. Development of CCA was inducedby initial feeding of 50 metacercariae of OV, followed by drinking water containing 12.5 ppm of DMN in hamsters.The ethanolic extract of A. lancea (Thunb.) DC. was administered orally for 30 days. PET-CT was performedevery 4 weeks after initiation of CCA using 18F-fluorodeoxyglucose (18F-FDG). Results from the present studysuggest that the ethanolic extract of A. lancea (Thunb.) DC. rhizome exhibited promising anti-CCA activityand safety profile in the OV/DMN-induced hamster model. To successfully apply PET-CT as a tool for earlydetection of tumor development and progression, modification of radiolabeling approach is required to improveits specificity for CCA cells.