New era of the management of NAFLD-associated hepatocellular carcinoma

As the obese population increases worldwide, nonalcoholic fatty liver disease (NAFLD) is becoming the one of leading cause of hepatocellular carcinoma (HCC). Although the incidence rate of HCC is not as high in NAFLD as in viral hepatitis, early detection of HCC is difficult due to huge number of NAFLD patients and absence of a specific method for surveillance for NAFLD-associated HCC. The recent development of noninvasive tests (NITs) such as fibrosis markers, scoring systems and elastographies have made it possible to evaluate hepatic fibrosis noninvasively. Narrowing down NAFLD with advance fibrosis (stage 3/4) using the combinations of NITs lead to efficient surveillance for HCC. In NAFLD patients with high GALAD score (> -0.63), high M2bpGi (> 1.26), and PNPLA3 GG homozygosity are reported to be at high risk for HCC and may require more stringent surveillance. In NAFLD-associated HCC, several factors involved in carcinogenesis, such as metabolic dysfunction, oxidative stress, dysbiosis and SNP (PNPLA3), potential factors involved in protective effect for carcinogenesis, such as prevention of diabetes, weight loss, smoking and alcohol cessation, and specific medication (statin, metformin, etc.) have been reported to be different from those of viral hepatitis-associated HCC. The development of appropriate surveillance for HCC, carcinogenesis prevention, and special treatment strategy for NAFLD-associated HCC are expected in the future.