Malignant epithelioma of the liver.

Introduction There are several congenital cystic conditions affecting the liver and bile ducts. The first group includes the intrahepatic cysts, which may be solitary or multiple, and their precursors, the von Meyenburg complexes. These are microscopic areas of duct ectasia which may enlarge gradually to form macroscopic cysts. The second group includes those lesions affecting the biliary drainage system itself, congenital hepatic fibrosis, cystic dilatation of the intrahepatic ducts, and choledochal cysts. The risk of malignant tumours complicating this second group of conditions has been recognized for some time. Bloustein (1977) assessed the incidence of malignant change as 1% in congenital hepatic fibrosis, 4% in choledochal cysts, and 7% in congenital cystic dilatation of the intrahepatic ducts. In contrast, malignancy in solitary non-parasitic cysts of the liver, or in polycystic liver disease has been described relatively rarely in single case reports by Willis (1943), Richmond (1956), Edmondson (1958), Ameriks, Appleman and Frey (1972), Greenwood and Orr (1972), an unpublished case but cited by Bloustein (1977), and 2 cases by Cruikshank (1961) in a series of primary liver cell carcinomas. A large series reported by Melnick (1955) includes 2 cases of benign neoplastic transformation of von Meyenburg complexes in 70 cases of polycystic liver disease, but no malignancies. Homer, White and Read (1968) have also described benign neoplastic change of von Meyenburg complexes in 2 cases, and an adenocarcinoma arising in a third.