A multicentric, open-label, single-arm prospective study to assess the efficacy and safety of tislelizumab combined with TACE as first-line treatment in patients with unresectable BCLC stage C HCC.

This is a multicentric, open-label, single-arm prospective study to assess the efficacy and safety of tislelizumab combined with conventional transarterial chemoembolization(cTACE) as first-line treatment in BCLC stage C HCC patients without extrahepatic spread. The primary endpoint is time to progression (TTP).

Inclusion Criteria:

1. 18-70 years old on the day the patients voluntary to participate in the study and signing in ICF.
2. Histological or clinical diagnosis of HCC.
3. BCLC stage C patients ineligible for surgical resection or liver transplantation.
4. No prior systemic therapy for HCC (including immunotherapy).
5. Have at least one uni-dimensional lesion measurable by CT scan or magnetic resonance imaging per mRECIST.
6. Child-Pugh A-B7.
7. ECOG PS 0-1.
8. Adequate hematological function (absolute neutrophil count ≥ 1.5 X 109/L, platelets count≥50 X109/L, and hemoglobin ≥85 g/L); Adequate hepatic function (both AST and ALT ≤ 3 ULN, serum total bilirubin ≤ 34.2 umol/L or 2mg/dl, serum albumin ≥ 29g/L); Adequate renal function (eGFR > 30 ml/min/1.73 m2)
9. For patients with HBV or HCV infection, HBV DNA less than 500 IU/ml (2500 copies/ml) or HCV RNA detectable.
10. life expectancy of more than 3 months.
11. Patients must be able to understand and willing to sign a written informed consent document.
12. Patients suitable for TACE therapy assessed by investigators.

Exclusion Criteria:

1. Tumor thrombus involving main trunk of portal vein or inferior vena cava.
2. Prior local-regional therapy before beginning of study treatment (surgery or ablation allowed at BCLC stage 0-B) or radiotherapy on liver cancer.
3. Disease history of grade 2 or more hepatic encephalopathy.
4. Extrahepatic metastasis on baseline imaging.
5. HIV infection or syphilis.
6. Prior therapies with any anti-PD-1, anti-PD-L1, anti-PD-L2 or anti-CTLA-4 agents.
7. Tumor diffuse.