Hepatocellular Carcinoma in Obesity, Type 2 Diabetes, and NAFLD

Hepatocellular carcinoma (HCC) is the second commonest cause of cancer death worldwide. Rather than falling as a result of prevention and treatments for viral hepatitis, an increase is evident in developed nations consequent to the rising prevalence of obesity and type 2 diabetes mellitus (T2DM)-the two major risk factors for nonalcoholic fatty liver disease (NAFLD). The majority of patients with HCC complicating these conditions present with advanced disease as the tools for surveillance are inadequate, and the "at-risk" population is not well characterized. This review will summarize the epidemiological evidence linking obesity, T2DM, and NAFLD with HCC, what is known about the pathogenic mechanisms involved, as well as their relevance for clinicians managing patients at risk. There will also be an overview of the "unmet needs" surrounding this topic, with suggestions for the direction translational research should take in order to prevent progression of NAFLD to HCC, to improve early detection of HCC in those with NAFLD, as well as to improve outcomes for those affected.