Background and objective: Non-small cell lung cancer (NSCLC) with mutations in the epidermal growth factor receptor (EGFR) is a distinct subgroup of NSCLC, which is particularly responsive to EGFR tyrosine kinase inhibitors (TKIs). The aim of this study is to detect EGFR mutations in paired serum of pre- and post-chemotherapy from advanced pulmonary adenocarcinoma patients to evaluate impact of chemotherapy on EGFR mutation status.
Methods: Magnetic beads were used for DNA extraction from paired serum of pre- and post-chemotherapy of 33 advanced pulmonary adenocarcinoma patients. The EGFR exon 19 and 21 were amplified by mutant-enriched nested PCR and analyzed by direct sequencing.
Results: EGFR mutations were detected in 39.4% (13/33) and 54.5% (18/33) serum samples of pre- and postchemotherapy, respectively. The EGFR mutation status was consistent in 54.5% (18/33) patients. Among 15 discordant cases, 10 changed from pre-chemo wild-type to post-chemo mutant-type status, while 5 from pre-chemo mutant-type to post-chemo wild-type status.
Conclusions: Chemotherapy may have influence on serum EGFR mutation status in advanced adenocarcinoma patients.
背景与目的: 存在表皮生长因子受体（epidermal growth factor receptor, EGFR）基因突变的非小细胞肺癌（non-small cell lung cancer, NSCLC）作为NSCLC的一个特殊亚群，对于表皮生长因子酪氨酸激酶抑制剂（epidermal growth factor receptor tyrosine kinase inhibitor, EGFR-TKI）的治疗显示出良好的疗效。本研究旨在检测晚期肺腺癌患者化疗前后血清EGFR基因外显子19和外显子21的突变状态，并分析化疗是否对EGFR基因突变状态产生影响。
方法: 磁珠法提取血清游离DNA后，使用酶切富集巢式PCR分别对血清游离DNA中EGFR外显子19和外显子21进行特异性扩增，应用直接测序法对EGFR基因突变状态进行检测。
结果: 33例肺腺癌患者化疗前EGFR基因突变率为39.4%（13/33），化疗后为54.5%（18/33），化疗前后EGFR基因突变状态的一致率为54.5%（18/33）；在不一致的15例患者中，10例由化疗前EGFR基因突变阴性变为阳性，5例由化疗前阳性变为阴性。
结论: 化疗可能导致血清EGFR基因突变状态的改变。