P2.01-93 The Analysis of the Soluble Programmed Death-1 of Lung Cancer Patients with Different Characteristics

Programmed death 1 ligand-1(PD-L1) is important regulators in cancer immunity. The aim of this study was to evaluate the values of the expression of the soluble programmed death-1(sPD-L1) in the plasma of patients with lung cancer, and to investigate the associations between the expression level of sPD-L1 and clinicopathological features as well as effective and survival outcomes. A total of 200 patients with non-small cell lung cancer (NSCLC)(n=188) and small cell lung cancer(SCLC)(n=12) treatment naive were explored, 96 samples of healthy subjects and 13 samples of benign tumours were studied as control. The sPD-L1 expression was scored by the way of anenzyme-linked immunosorbent assay (ELISA). We followed up 67 patients with NSCLC before and after standard treatment, and blood samples were taken every two months. We compared sPD-L1 expression with clinicopathological features and patients outcomes. The Expression of sPD-L1 in patients of lung cancer was significantly higher than benign tumour group and healthy group (3.01±3.00ng/ml, 1.76±1.74ng/ml, 1.82±1.20ng/ml, P=0.002). The level of sPD-L1 in lung cancer was not associated with gender, age, smoking history, and histologic subtypes (P＞0.05). The level of sPD-L1 was significantly higher in patients of worse PS (performance status)(PS≥2) than better PS(PS<2) (6.40±6.53 vs. 2.68±2.06 P=0.005). The level of sPD-L1 with later stages were remarkable higher than earlier stages (P<0.001) in NSCLC patients. The expression of sPD-L1 of the patients with epidermal growth factor (EGFR) mutated adenocarcinoma was higher than EGFR-wild group (4.30±1.82ng/ml vs. 3.76±1.57ng/ml, P=0.271). The decline of the level of sPD-L1 was correlated with the effects of good response and progressive disease (PD)(0.49±1.48ng/ml vs. 0.11±0.52ng/ml, P=0.307). As for survival, there was no difference between the decline of level of sPD-L1 and the progress free survival (PFS). Our results indicated that the elevated expression of sPD-L1 of patients with NSCLC was associated with later stages and worse life conditions, and which may correlated with bad clinical response and poor prognosis. EGFR mutation status may affect the expression of sPD-L1. Further studies are needed to determine the role of sPD-L1 as a molecular prognosis marker for the treatment and prognosis of patients with lung cancer.