[Liver Cancer]

Liver cancer is classified into primary and metastatic liver cancer. In Japan, hepatocellular carcinoma (HCC) accounts for about 95% and intrahepatic cholangiocarcinoma for about 4% of primary liver cancer. Recently, the prevalence of and mortality due to liver cancer have been rapidly decreasing in Japan. The main etiology of HCC is chronic infection of hepatitis B virus (HBV) and hepatitis C virus (HCV). However, the rate of these viral infections is decreasing, but the rate of HCC caused by non-alcoholic steato- hepatitis (NASH) is gradually increasing. The characteristic pathogeneses are multi-centric carcinogenesis, intrahepatic metastasis, and multi-step carcinogenesis. These pathogeneses are related to high rates of recurrence of HCC even after curative treatment. Clinical symptoms of HCC are rare in Japan because most patients with HCC are diagnosed by surveillance or incidental imaging analysis. HCC is diagnosed by not pathology but also classical images defined as showing early staining during the arterial phase and hypoattenuation compared with the surrounding non-tumorous liver during the portal or equilibrium phase (washout) on dynamic CT or MR. Three tumor markers: a-fetoprotein (AFP), protein induced by vitamin K absence or antagonist-II (PIVKA-II), and LCA-reactive a-fetoprotein isoform (AFP-L3), support the diagnosis. The surveillance of high-risk groups is recommended in Japanese Clinical Practice Guidelines for Hepatocellular Carcinoma 2013. Treatments for HCC are selected by considering the tumor progression and hepatic reserve and consist of surgery(hepatic resection, liver transplantation), local ablation therapy, transarterial chemoembolization (TACE), chemotherapy (sorafenib, hepatic arterial infusion chemotherapy), and radiation therapy. The algorithm for treatment selection is presented in the Japanese Clinical Practice Guidelines for Hepatocellular Carcinoma 2013. [Review].