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

Aims To investigate the implications of soluble programmed cell death-ligand 1 (sPD-L1) in hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE) and to evaluate the potential value of sPD-L1 to guide selection of the optimal time to begin combination therapy with TACE and immune checkpoint inhibitors (ICIs). Materials and methods Thirty-one HCC patients suitable for TACE and 55 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-L1 using enzyme-linked immunosorbent assay. The associations of the sPD-L1 level with the clinical features, outcomes, and the fluctuation of sPD-L1 during the treatment were analyzed. Results The initial sPD-L1 level of patients was significantly higher than that of the control group. And it was significantly associated with BCLC stage, portal venous invasion, tumor size, and number of foci. The sPD-L1 levels of 3 and 7 days after TACE were both significantly higher than the initial level. And that of 30 days after TACE was lower than the initial level, but the difference was not statistically significant. There was no significant difference of sPD-L1 level after embolization with embolic beads of different size. The level of sPD-L1 of CR patients was lower than that of PR, SD patients, but the differences were not significant. Conclusion The level of sPD-L1 was associated with tumor aggressiveness and outcomes, suggesting its role as a possible predictive biomarker. The increases in sPD-L1 after TACE suggests that combined treatment with TACE and ICIs may be a promising therapeutic strategy in HCC. One week after TACE might be a suitable time to begin the administration of immunotherapy.