Background: Ablation is important radical treatment in hepatocellular carcinoma (HCC). However, the 5-year recurrence rate of HCC after ablation is up to 80%. Early and late recurrences are more likely related to tumor size, tumor multiplicity, vascular invasion, higher serum AFP level and disease etiology, etc. Some studies suggested that adjuvant immunotherapy might be associated with decreased recurrence and prolonged RFS. Adjuvant atezolizumab + bevacizumab (IMbrave 050) showed RFS improvement following curative resection or ablation. Currently, there is limited study on immunotherapy combined with TKI as postoperative adjuvant therapy for HCC. This is an open-label, prospective cohort study to compare the efficacy and safety of tislelizumab plus tyrosine kinase inhibitor (TKI) as adjuvant therapy versus active surveillance in HCC patients with high risk of recurrence after curative ablation.

Inclusion Criteria:

• Eligible patients are ≥18 years, diagnosed with HCC confirmed by histopathology or cytology, with no prior targeted or immune checkpoint therapy for HCC, and have undergone curative ablation with no residual lesions according to imaging or pathological assessment. Patients are at high risk of recurrence meeting one of the following criteria:

solitary tumor >2cm but ≤5cm, or multiple tumors ≤4tumors and all≤5cm； poor tumor differentiation； macrovascular invasion of the portal vein(Vp1/Vp2) ； the absence or infiltration of a tumor capsule ； AFP≥32ng/ml； HBV DNA ≥105IU/ml； history of recurrence after curative treatment； family history of tumors.

Exclusion Criteria:

Concurrent with other primary malignant tumors; severe coagulation dysfunction or severe thrombocytopenic purpura; There is serious infection or organ failure; have previously received targeted drugs or other PD-1 antibody therapy;