 Of all cancers worldwide from 2002, 0.02% were cholangiocarcinoma caused by "Opisthorchis viverrini".The cancer of the bile ducts caused by opisthorchiasis occur in the ages 25–44 years in Thailand.A few cases have appeared in later life among veterans of the Vietnam war in the United States, who consumed poorly cooked fish from streams in endemic areas near the border of Laos and Vietnam.