Abstract: Objective To investigate the efficacy of immunosuppressants programmed death-1/ programmed death ligand-1 (PD-1/PD-L1) in the treatment of hepatocellular carcinoma (HCC) based on TumorFisher circuiting tumor cells (CTCs) assay. Methods 120 patients with middle and advanced HCC treated in Yancheng People's Hospital of Jiangsu Province from August 2021 to December 2022 were selected and divided into two groups, with 60 cases in each group. The control group was treated with drug-eluting beads trans-arterial chemoembolization (DEB-TACE) combined with tyrosine kinase inhibitor (TKI), and the observation group was treated with PD-1/PD-L1 immunosuppressant. Tumor response, TumorFisher CTCs, serum vascular endothelial growth factor receptor (VEGFR), matrix metalloproteinase-9 (MMP-9) levels and adverse reactions were compared, and progression-free survival (PFS) and overall survival (OS) were followed-up. Results The objective response rate (ORR)(71.67% vs 53.33%) and disease control rate (DCR)(81.67% vs 63.33%) were higher in the observation group (P<0.05). After treatment, the total CTCs, total PD-L1⁺CTCs and serum VEGF and MMP-9 levels were decreased in both groups, and the levels were lower in the observation group (P<0.05). There was no significant difference in the incidence of hand-foot syndrome, thrombocytopenia, hypothyroidism, kidney injury and neutropenia grade I/II and grade III in the observation group (P>0.05). The median PFS (8.26 months vs 5.81 months) and the median OS (19.51 months vs 14.43 months) were longer in the observation group (P<0.05). Conclusion PD-1/PD-L1 immunosuppressive agents can improve tumor response in patients with middle and advanced HCC, decrease total CTCs number, total PD-L1⁺CTCs number, serum VEGF and MMP-9 levels, prolong PFS and OS, without increasing adverse reactions.

Key words: Circuiting tumor cells, Programmed death-1, Programmed death ligand-1, Hepatocellular carcinoma