Advances in hepatocellular carcinoma: Nonalcoholic steatohepatitis-related hepatocellular carcinoma.

An increase in the prevalence of obesity and diabetes mellitus has been associated with the rise in nonalcoholic fatty liver disease (NAFLD). Two-thirds of the obese and diabetic populations are estimated to develop NAFLD. Currently, NAFLD is the most common etiology for chronic liver disease globally. The clinical spectrum of NAFLD ranges from simple steatosis, an accumulation of fat greater than 5% of liver weight, to nonalcoholic steatohepatitis (NASH), a more aggressive form with necroinflammation and fibrosis. Among the patients who develop NASH, up to 20% may advance to cirrhosis and are at risk for complications of end-stage liver disease. One of the major complications observed in patients with NASH-related cirrhosis is hepatocellular carcinoma (HCC), which has emerged as the sixth most common cancer and second leading etiology of cancer-related deaths worldwide. The incidence of HCC in the United States alone has tripled over the last three decades. In addition, emerging data are suggesting that a small proportion of patients with NAFLD may be at higher risk for HCC in the absence of cirrhosis - implicating obesity and diabetes mellitus as potential risk factors for HCC.