Hepatic and extrahepatic malignancies in NAFLD

Both hepatic and extrahepatic malignancies are a leading cause of morbidity and mortality among patients with overweight/obesity and/or diabetes mellitus. The increasingly prevalent obesity and related metabolic disorders may cause up to 20 % of cancer deaths and are expected to rapidly overcome the total health burden of cigarette smoking. Nonalcoholic fatty liver disease (NAFLD), which is the hepatic manifestation of the metabolic syndrome (MS), has increasingly been associated with an excess occurrence of cancer and increased risk of cancer-related mortality. Natural history studies have consistently reported that malignancies are among the most common causes of mortality, accounting for up to one third of deaths in NAFLD patients with diabetes. First and foremost, hepatic neoplasms, in particular hepatocellular carcinoma, have emerged as a notable threat to nonalcoholic steatohepatitis (NASH) patients, sometimes occurring in the absence of cirrhosis. Recent studies suggest that the NAFLD-related oncologic spectrum might extend beyond the liver, to colorectal cancer. In this chapter, we will review the association between NAFLD and hepatic and extrahepatic malignancies.