Enhancement of DEN-induced hepatocellular nodule development by Opisthorchis viverrini infection in Syrian golden hamsters.

The influence of Opisthorchis viverrini liver fluke infection on development of diethylnitrosamine (DEN)-induced hepatocellular nodules was investigated in Syrian golden hamsters. Infection with 60 metacercariae, 4 weeks prior to administration of DEN for 12 weeks in the drinking water at dose levels of 10, 20 and 40 p.p.m., resulted in a significantly increased yield of nodular lesions as compared with the group receiving carcinogen treatment alone. The results indicate an importance for parasite-associated liver injury and compensatory regeneration in hepatocarcinogenesis and suggest a possible role for Opisthorchis infestation in the generation of hepatocellular tumours in man.