The standard treatment for hepatocellular carcinoma (HCC) is surgery, such as, by hepatic resection or liver transplantation, but less than 20% of HCC patients are suitable for surgery. In the remaining patients with inoperable and advanced HCC, trans-arterial chemo-embolization (TACE) has been widely used but TACE alone rarely produces complete response and commonly develops recurrence. Recently several small studies reported high tumor response and local control rate after stereotactic body radiotherapy (SBRT) alone or with TACE for inoperable HCC. A single institution phase II trial with SBRT for inoperable HCC after incomplete TACE at Korea Cancer Center Hospital showed promising results: the overall response rate of 73% and 2-year local control rate of 95%. They reported severe gastrointestinal toxicity of 11% because there was no normal tissue constraint for gastrointestinal tract and dosage to gastrointestinal tract was restricted to the lowest levels possible. In addition, they found that the presence of gastroduodenal ulcer before SBRT was significantly influenced on severe gastrointestinal toxicity. Based on this study, we will conduct a multicenter phase II trial on maintenance of treatment results and reduction of severe treatment related toxicity below 5%. To achieve this, we strictly apply normal tissue constraints. Secondly, we will do Esophagogastroduodenoscopy (EGD) before SBRT to evaluate gastroduodenal ulcer. After then, we will apply the normal tissue constraint of gastrointestinal tract according to gastroduodenal ulcer.

Inclusion Criteria:

• Male or female patients ≥ 20 years of age
• Initially diagnosed or recurrent hepatocellular carcinoma (HCC)
• Unresectable HCC
• Inaccessible to local ablative treatment
• Cirrhotic status of Child Pugh class A or B7
• Eastern Cooperative Oncology Group performance status 0 or 1
• Tumor size < 10cm
• The volume of uninvolved must be at least 700 ml
• Incomplete response after trans-arterial chemo-embolization of 1-5
• A single lesion or multiple lesions including portal vein tumor thrombosis included in radiation field with one or consecutive sessions of SBRT
• No evidence of an uncontrolled lesion at any other site
• No evidence of complications of liver cirrhosis
• No evidence of uncontrolled inter-current illness
• Patient or guardian must be able to provide verbal and written informed consent

Exclusion Criteria:

• Patient with previous history of abdominal radiation
• Direct invasion to esophagus, stomach or colon by HCC