肺癌细胞学及血液标本表皮生长因子受体基因突变对比研究

摘要

目的：研究肺癌患者渗出液细胞学及血液标本中表皮生长因子受体（EGFR）第18、19、21外显子基因突变频率和类型以及与肿瘤组织学标本的关系。方法：收集肺癌患者渗出液细胞学标本53例及血液标本24例，提取 DNA，聚合酶链反应扩增 EGFR 外显子18、19、21序列，用直接测序法检测基因序列，分析 EGFR基因突变频率和类型以及与肿瘤组织学标本的关系。结果：53例细胞学标本检测到15例 EGFR 基因突变（28.3%，15/53），18外显子突变1例，19外显子突变5例，21外显子突变9例，细胞学标本与肺腺癌组织学标本突变率（32.2%）相比，差异没有显著性（P =0.624）。24例血液标本中检测到1例突变（4.2%，1/24），位于21外显子，血液标本与肿瘤组织学标本突变率相比，差异有显著性（P =0.006）。结论：肺癌患者渗出液细胞学标本适用于直接测序法检测 EGFR 突变，血液标本不适于用直接测序法检测肿瘤 EGFR 基因突变状态。%Objective:To determine the frequency and type of epidermal growth factor receptor(EGFR)exon 18, 19,21 exon mutations in cytology and blood specimens from lung carcinomas. To explore the relationship of EGFR mu-tation from cytology versus histology specimes. Methods:All 53 cytology specimens and 24 blood specimens were col-lected from patients with lung cancer. The tissue DNA was abstracted and the exons 18,19,21 in EGFR gene were subjected for PCR amplification and direct sequencing. Results:EGFR mutations were detected in 15 of 53 cytology specimens(28. 3% ),the frequencies of EGFR mutations in exons 18,19 and 21 were 1. 9%(1 / 53),9. 4%(5 / 53) and 16. 9%(9 / 53),respectively. There were no signifiant differences in the EGFR mutation rate between cytology samples and histology samples(28. 3 % VS 32. 2% ,P = 0. 624),but significant differences were found in the blood samples(4. 2% ,1 / 24,located in the exon 21)compared with histology samples(P = 0. 006). Conclusion:The cur-rent results indicate that direct extraction and analysis of EGFR mutations from cytology samples can be performed successfully on a direct sequencing platform. Peripheral blood is not a suitable compartment for detection of tumor cells in lung cancer.