This is a perspective clinical study to assess the safety and efficacy of PD-1 inhibitors in patients with LT. Eligible patients have recurrent or metastatic cancer after LT, are not amenable to, or refractory after, locoregional therapy or to a curative treatment approach (eg, surgery, or ablation) and have previously been treated with sorafenib or other targeted therapy, either intolerant to this treatment or show radiographic progression after treatment.

Biopsy is needed to exclude patients with positive allograft PD-L1 expression.

Inclusion Criteria:

1. Patients with recurrence or metastases Hepatocellular carcinoma after liver transplantation that not suitable for surgical resection and Local treatments such as radiofrequency ablation, transcatheter arterial embolization and radiotherapy, been treated with sorafenib or other targeted therapy and are either intolerant to this treatment or show radiographic progression after treatment.
2. Age 18-70 years old, male or female
3. Biopsy shows negative allograft PD-L1 expression
4. Child-Pugh score ≤ 6 points (Child-Pugh A)
5. Estimated postoperative survival time ≥ 12 weeks
6. ECOG score 0-1 points
7. Laboratory test indicators: white blood cells ≥ 3.0 × 109 / L, platelets ≥ 80 × 109 / L, hemoglobin ≥ 100g / L; total bilirubin ≤ 2.5 times the upper limit of normal, transaminase (AST, ALT) ≤ 2.5 times Upper limit of normal value, serum creatinine ≤ 1.5 times normal upper limit
8. Have sufficient understanding and voluntarily sign informed consent to participate in clinical research

Exclusion Criteria:

1. Biopsy shows positive allograft PD-L1 expression
2. Severe allergic reactions to other monoclonal antibodies
3. Have any history of active autoimmune diseases or autoimmune diseases
4. The presence of active infection with Hepatitis B or Hepatitis C Virus
5. Severe cardiopulmonary dysfunction patients, have high blood pressure and blood pressure can not be controlled with drugs, unstable coronary artery disease (uncontrollable arrhythmia, unstable angina), non-compensatory congestive heart failure, within 6 months Myocardial infarction