For the screening cohort, participants will undergo ultrasonography every 12 months if the findings are negative, and every 6 months if the diagnosis is positive for either periductal fibrosis of the bile duct, or fatty liver, or cirrhosis. They will be immediately referred to CT or MRI if they have liver mass or bile duct dilatation.For the patient cohort, treatment followup will be based on local routine care every 3 month for the first year and every 6 month thereafter. CASCAP will follow up all patients every year to update information on their health.