Descriptive epidemiology of cholangiocarcinoma and clonorchiasis in Korea.
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.
Shin
Hai-Rim
HR
International Agency for Research on Cancer, Lyon, France. shinhr@iarc.fr
Oh
Jin-Kyoung
JK
Lim
Min Kyung
MK
Shin
Aesun
A
Kong
Hyun-Joo
HJ
Jung
Kyu-Won
KW
Won
Young-Joo
YJ
Park
Sohee
S
Park
Sang-Jae
SJ
Hong
Sung-Tae
ST
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001650:Bile Duct Neoplasms / Q000453:epidemiology* / Q000469:parasitology; D001653:Bile Ducts, Intrahepatic / Q000469:parasitology / Q000473:pathology*; D018281:Cholangiocarcinoma / Q000453:epidemiology* / Q000469:parasitology; D003003:Clonorchiasis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged