EGFR mutation, expression of PD-L1/Ki-67 and their correlation with clinical features in elderly NSCLC patients / 中华检验医学杂志

ABSTRACT

Objective:To investigate the mutation of epidermal growth factor receptor (EGFR), the expression of programmed death ligand 1 (PD-L1), cell proliferation-associated antigen (Ki-67) in elderly patients with non-small cell lung cancer (NSCLC), and their correlation with clinical feature such as gender, histological type and TNM stage.Methods:The tissue samples of 340 elderly NSCLC patients with definite histopathological diagnosis were collected from January 2020 to December 2020 in Huadong Hospital Affiliated to Fudan University, including 195 males and 145 females, age between 68.9±6.0 years. Patients were grouped according to clinical features such as gender, histological type and TNM stage. The expression of EGFR mutation, PD-L1 and Ki-67 were detected by Super-ARMS and immunohistochemistry. The correlation between tnem and clinical features was statistically analyzed, and the correlation between EGFR mutation and PD-L1/Ki-67 expression was further analyzed separately.Results:In elderly NSCLC patients′ tissues, the positive rate of EGFR mutation was 48.53% (165/340). L858R and 19del mutations were the most common types, which were 56.36% (93/165), 30.30% (50/165) respectively. The mutation rate of EGFR was higher in women, lung adenocarcinoma, well-differentiated, and low-stage patients, which were 65.52% (95/145), 53.77% (164/305), 56.75% (143/252), 52.53% (135/257) respectively. In addition, the positive rate of PD-L1 expression was higher in elderly patients with non-adenocarcinoma lung cancer and poorly differentiated adenocarcinoma, which were 37.14% (13/35), 24.53% (13/53) respectively. The negative rate of PD-L1 expression was higher in elderly patients with NSCLC in stage Ⅰ+Ⅱ, no lymph node metastasis and weakly positive Ki-67, which were 89.11% (229/257), 87.63% (248/283), 94.71% (197/208) respectively. Correlation analysis showed that EGFR mutation was negatively correlated with the expression of PD-L1 and Ki-67 (PD-L1 r=-0.22, P<0.001; Ki-67 r=-0.32, P<0.001). Conclusion:There is a negatively correlation between EGFR mutation and the expression of PD-L1 and Ki-67 in elderly NSCLC, suggesting that the combined detection of EGFR mutation and PD-L1 expression could provide the basis for precise targeted therapy for elderly NSCLC patients.