**2.2 Viral hepatitis (hepatitis B and hepatitis C)**

Most HCCs develop from the background of chronic viral hepatitis, including hepatitis B and Hepatitis C [18–21]. Viral hepatitis-related HCCs are more common in countries where hepatitis B and hepatitis C are more prevalent, such as Asia and Africa. Viral-related HCC appears to be decreasing in countries where clinical follow-up increases, and whom include hepatitis B vaccine in regular vaccination programme. Integration of hepatitis B virus into the host hepatocyte genome is thought to initiate hepatocarcinogenesis. In the etiology of HCC, hepatitis C is as important as hepatitis B [22–24]. Being men and older, having coinfection (such as HBV, HIV), alcohol use, diabetes, and fatty liver constitute a high risk for HCC formation. Even the development of HCC in liver coinfected with hepatitis C and hepatitis B viruses, is higher than in those infected with other viruses [13]. It is thought that ongoing liver damage and accompanying regeneration caused by the immune response and direct cytopathic effect in hepatitis C infection induce malignant transformation [25, 26].
