ABSTRACT
@# Objective: To investigate the characteristics and clinical significance of the immunomicroenvironment typing based on the expression of programmed death-ligand 1 (PD-L1) and the infiltration of CD8+ T cells in the stroma in patients with non-small cell lung cancer (NSCLC). Methods: Paraffin tissue specimens and relevant clinicopathological data of 74 NSCLC patients admitted to our hospital from January 2016 to July 2018 were collected.All patients received EGFR gene test, and none received radiotherapy, chemotherapy or targeted therapy. Immunohistochemistry was used to detect the expression of PD-L1 in tissues and the infiltration of CD8+T cells in interstitium, and the relationship between PD-L1, CD8+T cells, and the immune microenvironment typing based on both, and the pathological parameters and the survival of patients was analyzed. Results: PD-L1 expression in the primary tumor of NSCLC patients showed statistical differences in gender, pathological type, smoking history, EFGR gene mutation status ( P <0.05). The infiltration of CD8+ T lymphocytes in tumor microenvironment showed statistically significant differences in different TNM stage and lymph node metastasis ( P <0.05), PD-L1 expression was significantly correlated with EGFR mutation ( P =0.000), while CD8+T lymphocyte infiltration was not correlated with EGFR mutation ( P =0.605). The immunomicroenvironment of EGFR wild-type patients was mainly (CD8+ PD-L1+) (type I), and the mutants were mainly (CD8-PD-L1-) (type II) and (CD8+PD-L1-) (type IV). The distribution of immune microenvironmental typing in each group with different EGFR mutation, smoking history and pathological differentiation degree was significantly different ( P <0.05) and significantly correlated with EGFR mutation ( P <0.05). Follow-up showed that the patients with disease free survival, recurrence and metastasis and death were the most in type I, type II and type I, respectively. Conclusions: In this study, the distribution of tumor immunomicroenvironmental typing in NSCLC patients was mainly the highest in type I and the lowest in type Ⅲ, which was related to EGFR mutation, smoking history and pathological differentiation. Patients with EGFR mutations were mainly of type Ⅱand type Ⅳ, and were associated with low expression of PD-L1. ··