Background: Epidermal growth factor receptor (EGFR) inhibitors are mainly used for the targeted therapy of non-small cell lung cancer (NSCLC). Therefore, EGFR mutations should be detected to treat lung cancer. The aim of this study is to determine the detection rate of NSCLC in patients with EGFR gene mutations by conducting direct sequencing and ARMS assay.
Methods: A total of 451 patients who were diagnosed with NSCLC between April 2012 and June 2013 participated in this study. Gene mutation was detected in the exon of EGFR 18 to 21 by direct sequencing and ARMS assay.
Results: All of the 451 cases of NSCLC were subjected to direct sequencing and ARMS assay. Using both techniques, we detected the same EGFR mutation in 127 cases and different EGFR mutations in 5 cases, but no mutations were detected in 186 cases. In direct sequencing alone, EGFR mutation was detected in 50 cases. In ARMS assay alone, EGFR mutation was detected in 83 cases. The mutation rates of direct sequencing and ARMS assay were 40.4% and 47.7%, respectively. Therefore, the mutation detection rate of ARMS assay was significantly higher than that of direct sequencing (P<0.001). In 204 paraffin tissue samples of NSCLC, the mutation detection rate of ARMS assay (59.80%) was significantly higher than that of direct sequencing (41.67%; P<0.001). By comparison, the mutation detection rates of ARMS assay (39.58%) and direct sequencing (38.33%) showed no significant difference (P=0.083) when 240 fresh tissue samples of NSCLC were used.
Conclusions: Direct sequencing and ARMS assay exhibited similar efficacy in detecting EGFR mutations. Despite its high operational costs, ARMS assay was more sensitive and more convenient than direct sequencing, particularly when a small number of tissues were used. By comparison, direct sequencing could detect mutations that were not detected by ARMS assay. Therefore, the combination of direct sequencing and ARMS assay could provide more reliable and comprehensive test results than the lone application of each technique.
背景与目的 以表皮生长因子受体（epidermal growth factor receptor, EGFR）为靶点治疗非小细胞肺癌（non-small cell lung cancer, NSCLC）是现在治疗肺癌的前沿手段，因此检测EGFR是否突变成为治疗肺癌的关键一步。本研究旨在探讨直接测序法和ARMS法检测NSCLC患者的EGFR基因突变情况及检出率。 方法 收集自2012年4月-2013年6月本中心接受进行EGFR基因突变检测的NSCLC患者，分别用直接测序法和ARMS法对这些患者的肿瘤组织标本进行检测，检测其中EGFR基因第18-21外显子的突变情况，并比较两者方法的优劣。结果 在该451例两种方法均检测的患者中，两种方法均检测到突变且突变结果一致者127例，结果不一致者5例，均无突变者186例，直接测序法检测到突变而ARMS法未检测到突变者50例，反之83例。50例中有33例为ARMS法29种突变之外的突变。直接测序法检测的突变率为40.4%，ARMS法检测的突变率为47.7%，ARMS法的突变检出率明显高于直接测序法（P<0.001）。在204例石蜡组织中，ARMS法的突变检出率59.80%明显高于直接测序法41.67%（P<0.001）；而在240例新鲜组织中，两种方法无统计学差异（P=0.083）。结论 直接测序法和ARMS法检测EGFR基因突变基本一致，ARMS法更为灵敏，且操作方便快捷，但是价格昂贵。对于肿瘤组织含量较少的样本中，ARMS法更为敏感，明显优于直接测序法。直接测序法可以检测到ARMS试剂盒内不包含的少见突变。结合两种方法检测结果更为可靠全面。