Macrovascular invasion (MVI) is common in HCC, Portal vein tumor thrombus (PVTT) is the most common form of MVI in HCC, with an incidence ranging from 44 to 62.2%. About 10% to 60% of HCC patients have PVTT at the time of diagnosis. the prognosis for those with PVTT remains poor, as their median survival is only 2-4 months via supportive care. There is currently no widely-accepted consensus for the management of HCC with PVTT. According to some guidelines in Europe and America, HCC with PVTT is regarded as Stage C per Barcelona Clinic Liver Cancer (BCLC) Staging system, and sorafenib alone is recommended as the treatment of choice. This study is to analyze the safety and efficacy of radiotherapy of hepatocellular carcinoma patients with portal vein tumor thrombosis.

Inclusion Criteria:

1. tumor thrombus involving the main trunk and/or first branches of the portal vein, unsuitable for surgery or TACE;
2. an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0-2; 3. no refractory ascites;

4. Child-Pugh class A and B, or class C with good performance status; 5. no previous radiotherapy to the liver; 6. more than 700 cc of uninvolved liver

Exclusion Criteria:

1. Have received local or systemic treatments in the past, including but not limited to TACE, immunotherapy, targeted therapy, radiotherapy, radiofrequency therapy, etc.;
2. Diffuse HCC or accompanied by distant metastasis;
3. Severe bleeding tendency or coagulation dysfunction within the previous 6 months;
4. Patients with a history of hepatic encephalopathy