Current status of hepatocellular carcinoma in Japan
Approximately 32,000 patients die of primary liver cancer each year in Japan. The annual number of deaths from primary liver cancer in Japan ranks second only to that in China in the world. In recent years, there has been a gradual trend towards decrease in the number of liver cancer patients from its peak in Japan, and this trend is expected to also continue in the future. The main reason for this decreasing trend was the establishment of screening of transfusion products for hepatitis B and hepatitis C viruses, which prevents transfusion-related transmission of the viral infection. Most patients with hepatocellular carcinoma (HCC) in Japan have underlying viral hepatitis, with hepatitis C accounting for about two-third of all the patients and hepatitis B accounting for about 15%. Regular screening of patients with viral hepatitis infection makes it possible to diagnose HCC early, and also enables effective loco-regional treatment, such as surgical resection, local ablative therapy and transcatheter arterial chemoembolization (TACE). However, HCC recurrence is encountered frequently even after these potentially effective treatments. After numerous loco-regional treatments for recurrent HCC, chemotherapy is administered for patients with highly advanced HCC. Among the modalities of chemotherapy, hepatic arterial infusion chemotherapy (HAIC) is employed more commonly than systemic chemotherapy, although no survival advantage has ever been demonstrated. Randomized controlled studies are currently under way to clarify the survival benefit of HAIC. Also, various novel systemic chemotherapeutic agents are currently under development in Japan, and further improvements in the treatment outcomes are expected.