Staging systems for hepatocellular carcinoma: Current status and future perspectives.

Hepatocellular carcinoma (HCC) is a major health concern worldwide and the third cause of cancer-related death. Despite advances in treatment as well as careful surveillance programs, the mortality rates in most countries are very high. In contrast to other cancers, the prognosis and treatment of HCC depend on the tumor burden in addition to patient's underlying liver disease and liver functional reserve. Moreover, there is considerable geographic and institutional variation in both risk factors attributable to the underlying liver diseases and the management of HCC. Therefore, although many staging and/or scoring systems have been proposed, there is currently no globally accepted system for HCC due to the extreme heterogeneity of the disease. The aim of this review is to focus on currently available staging systems as well as those newly reported in the literatures since 2012. Moreover, we describe problems with currently available staging systems and attempts to modify and/or add variables to existing staging systems.