Intrahepatic bile duct carcinoma and C. sinensis infection in Hong Kong.

Abstract

The prevalence of Clonorchis sinensis-induced ductal changes in Hong Kong patients with and without intrahepatic bile duct carcinomas was determined at autopsy. Among 19 patients with cholangiocarcinoma, 18 (94.7%) had adenomatous hyperplasia and ductal wall fibrosis characteristic of severe clonorchiasis. Such changes were found in only one third of control patients without a bile duct cancer. None of the patients with cholangiocarcinoma had cirrhosis. The nearly constant presence of severe clonorchiasis in patients with intrahepatic bile duct cancer, the close physical relationship of the main tumor mass to infected ducts, the frequent coexistence in the same duct of focally atypical epithelial hyperplasia and invasive cancer, and the results of animal experiments reported in pertinent literature all support a cause-to-effect relationship between clonorchiasis and endemic intrahepatic bile duct cancer. It was concluded that C. sinensis infection exerts a mild but essential carcinogenic effect and, therefore, eradication of endemic clonorchiasis should result in the virtual elimination of endemic intrahepatic cholangiocarcinoma in Hong Kong.