免疫组织化学标记检测肺腺癌表皮生长因子受体基因E746-A750缺失和L858R点突变的临床应用

using epidermal growth factor receptor mutation-specific antibodies of delE746-A750 and L858R in lung adencarcinomas

目的研究2种表皮生长因子受体（EGFR）突变特异性抗体外显子19中E746-A750缺失和外显子21中L858R点突变的免疫组织化学标记在肺腺癌EGFR突变检测中的应用价值。方法应用2种抗EGFR突变特异性单克隆抗体E746-A750缺失和L858R点突变对175例石蜡包埋的肺腺癌组织进行免疫组织化学检测，这些病例以往均曾通过直接DNA测序进行过EGFR突变检测。结果免疫组织化学和直接基因测序2种方法在检测delE746-A750和L858R总体突变率方面并无明显差异[33．7％（59／175）和30．9％（54／175），P〉0．05]。以基因测序结果为金标准，免疫组织化学检测的敏感性、特异性、阳性预测值和阴性预测值分别为83．1％、95．7％、90．7％和90．9％。结论EGFR突变特异性抗体E746-A750缺失和L858R点突变的免疫组织化学标记在检测石蜡包埋的肺腺癌EGFR基因突变方面具有较高的敏感性和特异性，是一种经济、快捷和高效的EGFR突变筛选方法。

Objective To evaluate the immunohistochemical detection of epidermal growth factor receptor（EGFR） mutations using two EGFR mutation-specific monoclonal antibodies： delE746-A750 and L858R. Methods A total of 175 paraffin-embedded lung adenocarcinoma tissue samples previously genotyped by directive DNA sequencing were subject to immunostaining using delE746-A750 and L858R antibodies. Results There was no significant difference of mutation detection between DNA sequence analysis and delE746-A750 and/or L858R immunostaining （ 33.7% vs 30. 9% , P 〉 0. 05 ）. The overall sensitivity, specificity, positive predictive value and negative predictive value of immunostaining using these two EGFR mutation-specific antibodies were 83.1%, 95.7%, 90.7% and 90.9%, respectively. Conclusion With high sensitivity and good specificity, immunohistochemistry using EGFR mutationspecific monoclonal antibodies is an adequate, easy and cost-effective prescreening method to detect EGFR mutations using paraffin-embedded tissue specimens of lung adenocarcinomas.