Liver Cancer and Fibrosis-Cirrhosis
Hepatocellular carcinoma (HCC)—cancer of the liver parenchyma and the most common form of liver cancer—is the fifth most prevalent form of cancer worldwide and the third leading cause of cancer death, killing approximately 700,000 each year. In the US, HCC is one of the few forms of cancer whose incidence is increasing and is the fastest growing cause of cancer mortality. Cholangiocarcinoma (CCA)—cancer of the biliary tree and bile duct—is the second most common form of liver cancer. Overall survival for both HCC and CCA is limited, as the vast majority of patients currently present with symptomatic, late-stage disease ineligible for potentially curative treatment. Early detection of HCC and CCA remains a serious unmet clinical need. Effective non-invasive monitoring of liver fibrosis also remains a challenge, with core biopsy still regarded as the “gold standard”.
Populations at risk for liver fibrosis-cirrhosis and HCC largely fall into two categories. Viral hepatitis—chronic hepatitis B and C infections—historically has been the most important predisposing condition. Hepatitis B, especially in Asian populations, is a significant cause of progressive fibrosis-cirrhosis and HCC, with half of all HCC deaths worldwide occurring in China. In the US hepatitis C is an even more prevalent threat. However, skyrocketing obesity and fatty liver disease and the non-viral hepatitis (NASH; non-alcoholic steatohepatitis) they cause are making liver cancer an increasingly Western health threat. The scope of this challenge for early detection is made clear by estimates that up to 15 million people in the US have NASH and one-third of the total US population has fatty liver disease.