738P - Soluble programmed death-ligand 1 indicate poor prognosis in hepatocellular carcinoma patients undergoing transcatheter arterial chemoembolization

Abstract

BackgroundSoluble programmed death-ligand 1 (sPD-L1) is associated with hepatocellular carcinoma (HCC) prognosis after resection or radiotherapy. However, its value in patients who received transcatheter arterial chemoembolization (TACE) remains unclear. The present study aimed to determine the prognostic significance of sPD-L1 in TACE subgroup. Methods114 HCC patients with hepatitis B virus (HBV)-background who received TACE from 2012 to 2013 were recruited. sPD-L1 levels were determined by enzyme-linked immunosorbent assay. We evaluated prognoses according to mRESIST criteria and analyzed prognostic values by Cox regression and Kaplan-Meier analysis. We further evaluated correlations between sPD-L1 and systemic inflammation index (SII), soluble interleukin-2 receptor (sIL-2R), IL-10, hepatitis B virus (HBV)-DNA loads, and C-reactive protein. ResultsSignificantly elevated sPD-L1 levels were found in patients who developed HCC progression (P=0.002) and death (P<0.001). Patients with higher pre-treatment sPD-L1 levels had a significantly shorter time to progression (10.50 vs. 18.25 months, P=0.001) and decreased overall survival (16.50 vs. 28.50 months, P=0.003). In low-recurrence-risk subgroups, sPD-L1 levels retained prognostic value (P<0.050). Importantly, multivariate regression confirmed that pre-treatment sPD-L1 level was an independent predictor for both progression [hazard ratio (HR) 1.82; P=0.032] and survival (HR 1.84; P=0.009). Moreover, sPD-L1 levels positively correlated with SII (r=0.284, P=0.002), sIL-2R (r=0.239, P=0.010), IL-10 (r=0.283, P=0.002), HBV-DNA loads (r=0.229, P=0.014), and CRP (r=0.237, P=0.011). ConclusionssPD-L1 level is a prognostic indicator of poor outcomes after TACE. High sPD-L1 indicated increased immune activation in an immunosuppressive environment that hindered anti-tumor response activity. Lowering sPD-L1 levels may provide a novel avenue for preventing HCC progression post-TACE. Legal entity responsible for the studyThe authors. FundingThe National Natural Science Foundation of China (87172263 and 81572064) and Key Developing Disciplines of Shanghai Municipal Commission of Health and Family Planning (2015ZB0201). DisclosureAll authors have declared no conflicts of interest.