In 2009, infection with the liver fluke Clonorchis sinensis (C. sinensis) was classified as "carcinogenic to humans" (Group 1) based on its involvement in the etiology of cholangiocarcinoma by the International Agency for Research on Cancer. However, little is known about the descriptive epidemiology of cholangiocarcinoma in Korea. We examined incidence trends of intrahepatic and extrahepatic cholangiocarcinomas, using data from the Korea National Cancer Incidence database for 1999-2005. The prevalence of C. sinensis infection was estimated from a recent population-based survey in rural endemic areas. Cholangiocarcinoma incidence rates are currently rising, even while primary liver cancer incidence rates are decreasing. Annual percent changes in cholangiocarcinoma incidence rates were 8% for males and 11% in females. Known areas of C. sinensis endemicity showed high incidence rates of cholangiocarcinoma. The positivity of C. sinensis eggs in stool samples from endemic areas was more than 25% of adults tested during 2005-2008. From a meta-analysis, the summary odds ratio for cholangiocarcinoma due to C. sinensis infection was 4.7 (95% confidence interval: 2.2-9.8). Approximately 10% of cholangiocarcinomas in Korea were caused by chronic C. sinensis infections. More specific policies, including health education and an extensive effort for early detection in endemic areas, are needed.
Adult ; Aged ; Aged, 80 and over ; Animals ; Bile Duct Neoplasms/*epidemiology/parasitology ; Bile Ducts, Intrahepatic/parasitology/*pathology ; Cholangiocarcinoma/*epidemiology/parasitology ; Clonorchiasis/*epidemiology ; Female ; Humans ; Korea/epidemiology ; Male ; Middle Aged

No abstract available.
Animals ; Bile Duct Neoplasms/*diagnosis/parasitology/pathology ; *Bile Ducts, Intrahepatic ; Cholangiocarcinoma/*diagnosis/parasitology/pathology ; Clonorchiasis/*complications/pathology ; Clonorchis sinensis/*isolation & purification ; Humans ; Male ; Middle Aged

This study describes an evaluation of the sonographic, cholangiographic, pathological, and immunological findings, and the protective effect shown by rats reinfected with Clonorchis sinensis. Eight experimental rat groups were, namely, a normal control, a primary infection control, a reinfection I (reinfection 7 week after treatment following 3-week infection), a reinfection II (reinfection 2 week after treatment following 8-week infection), a reinfection III (exploration of the intrahepatic bile ducts 1 week after reinfection 4 week after treatment following 4-week infection), a superinfection, a secondary infection control, and an infection following immunization group. Sonographic and cholangiographic findings showed moderate or marked dilatation of the bile duct confluence in the primary infection control, reinfection II, and secondary infection control groups. Juvenile worms survived in the intrahepatic bile ducts 1 week after reinfection following treatment in the reinfection III group. It was concluded that reinfecting juvenile worms found during the first week following reinfection failed to survive or grow further. Anatomical, pathophysiological, or immunological changes may induce protection from reinfection in rats.
Animals ; Anthelmintics/administration & dosage/therapeutic use ; Antibodies, Helminth/blood ; Antigens, Helminth/administration & dosage/immunology ; Bile Duct Diseases/parasitology/*pathology/ultrasonography ; Bile Ducts, Intrahepatic/parasitology/*pathology/ultrasonography ; Cholangiography ; Clonorchiasis/parasitology/*pathology/ultrasonography ; Clonorchis sinensis/*pathogenicity ; Immunization ; Praziquantel/administration & dosage/therapeutic use ; Rats ; Rats, Sprague-Dawley ; Sound Spectrography ; Support, Non-U.S. Gov't