Liver fluke and cholangiocarcinoma in Thailand

Abstract

In northeastern Thailand, prevalent risks for cholangiocarcinoma (CC) include infestation with liver fluke O. viverrini (OV), infection with HBV and HCV, and consumption of nitrosamine-rich foods. The ASR for intrahepatic cholangiocarcinoma (ICC) is the highest in the world (44 and 16 per 100,000 males and females). ICC accounts for 58% of cases, exceeding that of hepatoma (42%). As per the AJCC-2009, the spectrum of CC among the 221 patients operated at Khon Kaen University Hospital included: perihilar CC (52.9%); ICC (37.1%); distal extrahepatic CC (4.1%) and combined ICC and extrahepatic CC (5.8%). Peak age incidence was in the sixth decade, about 5–10 years younger than sporadic CC. Chronic inflammation associated with OV infestation may be a contributing factor for the spectrum of CC vs HBV or HVC, since ICC with cirrhosis is rare and the phenotypes related to chronic hepatitis (CC and cholangio-hepatoma) account for <3%. Studies comparing OV-associated CC and sporadic CC shared similar pathological features, precursor lesions, growth factors and molecular alterations (like pancreatic ductal carcinoma). In northeastern Thailand, prevalent risks for cholangiocarcinoma (CC) include infestation with liver fluke O. viverrini (OV), infection with HBV and HCV, and consumption of nitrosamine-rich foods. The ASR for intrahepatic cholangiocarcinoma (ICC) is the highest in the world (44 and 16 per 100,000 males and females). ICC accounts for 58% of cases, exceeding that of hepatoma (42%). As per the AJCC-2009, the spectrum of CC among the 221 patients operated at Khon Kaen University Hospital included: perihilar CC (52.9%); ICC (37.1%); distal extrahepatic CC (4.1%) and combined ICC and extrahepatic CC (5.8%). Peak age incidence was in the sixth decade, about 5–10 years younger than sporadic CC. Chronic inflammation associated with OV infestation may be a contributing factor for the spectrum of CC vs HBV or HVC, since ICC with cirrhosis is rare and the phenotypes related to chronic hepatitis (CC and cholangio-hepatoma) account for <3%. Studies comparing OV-associated CC and sporadic CC shared similar pathological features, precursor lesions, growth factors and molecular alterations (like pancreatic ductal carcinoma).