Stereotactic Ablative Radiotherapy for Hepatocellular Carcinoma With Major Portal Vein Invasion

Inclusion Criteria: * Male or female patients ≥ 20 years of age * Initially diagnosed or recurrent hepatocellular carcinoma (HCC) * Eastern Cooperative Oncology Group performance status 0 or 1 * HCC with major portal vein tumor thrombosis (tumor thrombosis in the main portal vein or 1st branch of portal vein) * Cirrhotic status of Child Pugh class A or B7 * Patients can have extra-hepatic disease; provided the hepatic disease is the highest burden, the extra-hepatic disease is low burden and potentially treatable with radiotherapy, chemotherapy and target agent etc; patient survival is expected to be at least 6 months. * Patient or guardian must be able to provide verbal and written informed consent Exclusion Criteria: * Prior trans-arterial chemo-embolization ≥4 after diagnosis of major portal vein tumor thrombosis * Severe complication caused by liver cirrhosis eg. variceal bleeding, poorly controlled ascites, hepatic encephalopathy) * Uncontrolled inter-current illness except liver cirrhosis