The influence of transarterial chemoembolization on serum levels of soluble programed cell death protein-1 in advanced hepatocellular carcinoma patients

Abstract Aims To investigate the implications of soluble programmed cell death protein 1 (sPD-1) in hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE) and to evaluate the potential value of sPD-1 to guide selection of the optimal time to begin combination therapy of TACE and immune checkpoint inhibitors (ICIs). Materials and methods Forty-four HCC patients suitable for TACE and fifty-five healthy volunteers were enrolled in this study. Three milliliters of peripheral venous blood of patients were collected on 1 day before TACE and 3, 7, and 30 days after TACE respectively for assay of sPD-1 using enzyme-linked immunosorbent assay. The associations of the sPD-1 level with the clinical features, outcomes, and the fluctuation of sPD-1 during the treatment were analyzed. Results The initial sPD-1 level of patients was significantly higher than that of the control group. Although the initial level of sPD-1 showed a decreasing trend with the increase of BCLC stage, there were no significant differences among patients with different BCLC stages. The sPD-1 level of 3 and 7 days after TACE was significantly lower than the initial level. The sPD-1 level of 30 days after TACE was significantly higher than that of 7 days after TACE and nearly elevated to the initial level before TACE. The level of sPD-1 of CR and PD patients was lower than that of PR, SD patients, but the differences were not significant. Conclusion The level of sPD-1 was significantly elevated in patients with HCC but further research is necessary to better understand the value of sPD-1 in onset, development, and prognosis of HCC as a potential biomarker. The decreases in sPD-1 after TACE suggested that TACE could probably reduce immune effector cells as well as weaken immune function, which indicated that the ICIs shouldn’t be administered shortly after TACE.