This study is conducted to evaluate the efficacy and safety of transarterial chemoembolization (TACE) combined with lenvatinib and iodion-125 seeds brachytherapy (TACE-Len-I) compared with TACE combined with lenvatinib (TACE-Len) for hepatocellular carcinoma (HCC) with portal vein branch tumor thrombus (branch PVTT).

This is an single center, randomized controlled trial to evaluate the efficacy and safety of TACE-Len-I compared with TACE-Len for the treatment of HCC with branch PVTT.

171 HCC patients with branch PVTT will be enrolled in this study. The Patients will be treated with TACE-Len-I or TACE-Len using an 2:1 randomization scheme.

TACE will be performed for the patients after randomization. Lenvatinib (body weight ≥ 60 kg, 12mg P.O. QD; body weight < 60 kg, 8mg P.O. QD) will be started at 3-7 days after the first TACE and last until disease progresses, intolerable toxicity, withdrawal of informed consent, loss of follow-up, death, or other circumstances that require termination of treatment, whichever occurs first. For patients in the TACE-Len-I arm, iodion-125 seeds will be implanted into the PVTT (according to the pre-operative planning) under CT guidance within 14 days after the first TACE. TACE and iodion-125 seeds implantation can be repeated on demand during follow-up based on the evaluation of laboratory and imaging examination.

Inclusion Criteria:

1. Age between18 and 75 years.
2. HCC confirmed by histopathology and/or cytology, or diagnosed clinically.
3. Accompanied with tumor thrombus involving unilateral portal vein branch.
4. Child-Pugh class A or B.
5. Eastern Cooperative Group performance status (ECOG) score of 0-2.
6. Serum bilirubin ≤ 51.3 μmol/L, albumin ≥ 28g/L, ALT and AST ≤ 5 times of the upper normal limit, and creatinine ≤ 20g/L.
7. Prothrombin time prolonged for less than 4s or international normalized ratio < 1.7.
8. Neutrophilic granulocyte count ≥ 1.5×10^9/L, platelet count ≥ 50×10^9/L, and hemoglobin level ≥ 85g/L;
9. At least one measurable intrahepatic target lesion.
10. Life expectancy of at least 3 months.

Exclusion Criteria:

1. Diffuse HCC.
2. Extrahepatic metastasis.
3. Tumor thrombus involving both the left and right branch of portal vein or main portal vein.
4. Hepatic vein and/or vena cava invasion.
5. History of organ or cells transplantation.
6. Previous treatment with TACE, intra-arterial infusion chemotherapy, radiotherapy or systemic therapy.
7. History of other malignancies.
8. Serious medical comorbidities.
9. Female patients who are pregnancy or breastfeeding.