CD274 and hepatocellular carcinoma: A systematic review and meta-analysis for first-line and second-line phase II/III studies were conducted on immunotherapy for patients with advanced HCC by using OS as the primary outcome measure, and PFS and ORR as the secondary outcome measures to obtain clinico-pathological characteristics of patients which might be preferable responses to programmed death-1 (PD-1) and programmed cell death-Ligand 1 (PD-L1) inhibitors.