Liver cancer is a form of cancer with a high mortality rate. Liver cancers can be classified into two types. They are either primary, when the cancer starts in the liver itself; or metastatic, when the cancer has spread to the liver from some other part of the body.

Primary liver cancer is a relatively rare disease in the United States, representing about 2% of all malignancies. It is, however, much more common in other parts of the world, representing from 10-50% of malignancies in Africa and parts of Asia. The American Cancer Society estimates that in 1998, at least 14,000 new cases of liver cancer will be diagnosed. It will also cause roughly 13,000 deaths in the United States in 1998.

In adults, most primary liver cancers belong to one of two types: hepatomas, or hepatocellular carcinomas, which start in the liver tissue itself; and cholangiomas, or cholangiocarcinomas, which are...