Tumor immunology: Hepatocellular carcinoma, cholangiocarcinoma, and metastatic neoplasms

Abstract

Most tumors of the liver arise from hepatocytes giving rise to hepatocellular carcinoma (HCC), or biliary epithelial cells giving rise to cholangiocarcinoma (CCA), or the tumors are metastatic, often from colon cancer. HCC and CCA are associated with other diseases of the liver, which often incite chronic inflammation. In the case of HCC, chronic viral hepatitis is often present, although other non-inflammatory liver diseases such as hemochromatosis and α1-antitrypsin deficiency also increase the risk of HCC. Inflammatory conditions of the biliary tract, including liver fluke infestation and primary sclerosing cholangitis, are associated with CCA. These findings suggest that the immune response plays an important role in the development of many of these tumors. However, the immune response to tumors may be equally important in preventing the development or progression of liver tumors. Furthermore, directing an immune response against tumor cells has been a goal of many cancer vaccine trials, with some promising results. © 2007 Humana Press Inc.