Breast, bowel, or stomach cancers are tumor diseases that many people have heard of. It is less well known that malignant tumors also not uncommonly arise in the liver. These usually occur in one of two variations: in the form of liver metastases, in other words, groups of tumor cells from other tissues which arrive in the liver and begin growing there. Alternatively, the cancer can develop directly from the liver cells. In this case, the tumor is called hepatocellular carcinoma (HCC). It is the fifth most common malignant tumor worldwide and the third most frequent cause of cancer-related death. In most cases, HCC develops from chronic liver disease that has resulted in liver cirrhosis. Liver cirrhosis is caused by viral infections of the liver in particular and also by metabolic disorders, chronic fatty liver, and excessive alcohol consumption.
Tumors can develop from the bile ducts (biliary system) as well. These are called cholangiocarcinomas. There are large bile ducts outside the liver (including gall bladder), as well as smaller ducts situated inside the liver, from which tumors can develop. Hepatocellular carcinoma and cholangiocarcinomas belong to the group of hepatobiliary cancers.