Liver disease comprises a wide range of complex conditions that affect the liver and prevent the organ from functioning effectively. Some liver diseases are associated with increased risk for cancer, including cirrhosis and fatty liver disease (FLD) while others can be genetic or caused by a variety of factors that damage the liver. 
Some types of liver disease, especially those that are genetically induced, present early in life and progress rapidly. More commonly, liver disease develops over many years, often going unnoticed until later in life when significant liver damage has already occurred.
Liver disease has a global prevalence of approx. 2 million deaths per year. Out of those, half are due to complications of cirrhosis and the other half due to viral hepatitis and hepatocellular carcinoma. Liver cirrhosis and liver cancer account for 3.5% of all deaths and are both under the top 20 most common causes of global mortality (cirrhosis: 11th, liver cancer: 16th).