非小细胞肺癌不同样本中EGFR基因突变、PD-L1表达检测的一致性

Consistency of EGFR gene mutation and PD-L1 expression in different specimens of non-small-cell lung cancer

目的分析非小细胞肺癌(NSCLC)患者不同样本(肿瘤组织、胸腔积液及血液样本)中EGFR基因突变、程序性死亡配体1(PD-L1)表达检测的一致性。方法收集150例NSCLC患者的肿瘤组织、胸腔积液及血液样本,制作蜡块标本,用扩增阻遏突变系统-实时荧光定量聚合酶链反应检测各样本EGFR基因突变,免疫组化法检测肿瘤组织、胸腔积液中PD-L1蛋白表达;用Kappa检验分析各样本类型检测结果的一致性。结果胸腔积液与肿瘤组织样本EGFR基因突变检测结果一致性极好(Kappa=0.878,P<0.05),血液与肿瘤组织样本EGFR基因突变检测结果一致性极好(Kappa=0.813,P<0.05);当以PD-L1蛋白表达阳性细胞百分比≥50%为阈值时,胸腔积液与肿瘤组织样本中PD-L1蛋白表达的一致性较差(Kappa=0.326,P>0.05);当以PD-L1蛋白表达阳性细胞百分比≥1%为阈值时,胸腔积液与肿瘤组织样本中的PD-L1蛋白表达的一致性较差(Kappa=0.367,P>0.05)。结论NSCLC患者胸腔积液、血液样本中的EGFR基因突变检测与肿瘤组织样本的一致性较高,胸腔积液中PD-L1蛋白检测与肿瘤组织样本的一致性较差。

Objective To analyze the consistency of epidermal growth factor receptor(EGFR)gene mutation and programmed death-ligand 1(PD-L1)expression in different specimens(tumor tissue,pleural effusion and blood samples)of patients with non-small-cell lung cancer(NSCLC).Methods Tumor tissues,pleural effusion and blood specimens of 150 patients with NSCLC were collected.The pleural effusion specimen was embedded into cell wax blocks.ARMS-PCR was used to detect the mutation of EGFR in different specimens.The expression of PD-L1 protein in the tumor tissues and pleural effusion was evaluated by immunohistochemistry.Kappa consistency test was used to analyze the consistency of results in different specimens.Results The consistency of EGFR gene mutation in pleural effusion and tumor tissue specimens was excellent(Kappa=0.878,P<0.05).The consistency of EGFR gene mutation in blood and tumor tissue specimens was excellent(Kappa=0.813,P<0.05).When the percentage of tumor cells positive for PD-L1 protein expression≥50% was used as the threshold,the expression consistency of PD-L1 in pleural effusion and tumor tissue specimens was poor(Kappa=0.326,P>0.05);when the percentage of tumor cells positive for PD-L1 protein expression≥1% was used as the threshold,the expression consistency of PD-L1 in pleural effusion and tumor tissue specimens was poor(Kap⁃pa=0.367,P>0.05).Conclusions The detection of EGFR gene mutation in blood and pleural effusion specimens is highly consistent with that in tumor tissue specimens of NSCLC patients.The expression of PD-L1 in pleural effusion specimens is poor consistent with that in tumor tissue specimens.