非小细胞肺癌表皮生长因子受体20号外显子插入突变检测临床实践中国专家共识(2024版)

中国肺癌人群中约82%为非小细胞肺癌, 表皮生长因子受体(EGFR)基因则是中国肺癌人群中最常见的驱动基因突变(51.7%～54.4%)。近年来靶向治疗特别是EGFR酪氨酸激酶抑制剂的快速发展及广泛应用显著提高了中国肺癌患者的生存时间及生存质量。EGFR基因20号外显子插入突变(EGFR ex20ins)在中国非小细胞肺癌患者中发生率约为0.3%～2.9%, 居EGFR基因突变第3位, 目前已有多个针对性靶向药物研发。然而EGFR ex20ins的变异类型众多, 具有高度分子异质性, 检测难度较高, 临床检测需进一步规范。明确EGFR ex20ins检测临床意义、适用人群及不同检测方法优劣势, 规范报告内容, 对提高EGFR ex20ins检测准确性具有重要意义。针对EGFR ex20ins检测的实际问题, 中国抗癌协会肿瘤病理专业委员会分子病理协作组和中国医师协会肿瘤多学科诊疗专业委员会结合国内外多中心研究及临床实践经验, 组织专家讨论并制定了非小细胞肺癌EGFR ex20ins检测临床实践中国专家共识(2024版), 以期指导临床EGFR ex20ins检测实践。     

特异引物双扩增实时PCR法和Sanger DNA测序法检测肺癌组织中表皮生长因子受体基因突变

目的 探讨特异引物双环探针扩增实时PCR技术表皮生长因子受体(EGFR)检测方法(ADx-EGFR实时PCR法)和Sanger DNA测序法在肺癌EGFR基因体细胞突变检测中的临床价值.方法 收集肺癌组织石蜡切片208例,分别采用ADx-EGFR实时PCR法和Sanger DNA测序法检测肺癌组织中EGFR基因外显子18、19、20、21的突变类型,计算其突变率,分析两种检测方法检测EGFR基因突变的一致性.结果 208例肺癌组织中,ADx-EGFR实时PCR法成功检测208例,检出EGFR基因突变40例,突变检出率为19.2％;Sanger DNA测序法成功检测196例,检出突变22例,突变检出率为11.2％.肺癌组织中主要以外显子19缺失和外显子21上的L858R的点突变为主,分别占4.8％ (10/208)和11.6％ (23/208),其余的突变类型少见.结论 对于甲醛固定石蜡包埋组织而言,ADx-EGFR实时PCR法检测EGFR基因成功率和突变检出率均高于Sanger DNA测序法,可成为临床上检测肿瘤EGFR基因突变的方法.     

血清循环DNA的EGFR基因突变与肺癌选择性靶向治疗研究

目的:通过血清循环DNA的基因突变检测,筛选EGFR突变型肺癌患者并评估靶向性药物吉非替尼对其的临床疗效。方法:从肺癌患者血清中提取DNA,采用PCR扩增和基因测序检测EGFR突变。结果:116例肺癌血样中检出EGFR突变46例,突变率为39.7%,其中外显子19和21突变分别占65.2%(30/46例)和34.8%(16/46例),EGFR基因突变多见于女性患者和肺腺癌(包括腺鳞癌)患者。对20例肺癌的进一步分析证明,血清EGFR基因突变类型与患者自身肿瘤的突变类型相同。另外通过血清循环DNA基因检测法筛选了19例化疗失败的突变型晚期肺癌进行吉非替尼靶向治疗,客观有效率为52.6%,病情控制率为89.5%,中位无进展生存时间为8个月,中位生存时间为12个月,2年生存率达到33.3%。结论:证实血清循环DNA与肿瘤组织DNA的EGFR基因突变一致;以血清循环EGFR突变检测结果为依据选择分子靶向性药物吉非替尼治疗,对晚期肺癌患者疗效明显。     

非小细胞肺癌患者血清EGFR基因突变循环DNA检测

目的:探讨循环DNA测定表皮生长因子受体(epidermal growth factor receptor,EGFR)突变的可行性;旨在提供更方便、快捷、无创的分子生物检测手段,指导晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者靶向治疗。方法:收集石河子大学医学院第一附属医院2011-09-21-2012-09-30接受靶向治疗(吉非替尼或厄洛替尼)的48例晚期NSCLC患者血清及相应石蜡组织标本DNA,采用直接测序法检测EGFR基因19和21外显子的突变情况,应用SPSS17.0软件进行统计学分析。结果:48例患者循环DNA中EGFR基因突变检出率为14.583%(7/48),且与组织DNA检测出EGFR突变类型一致,即19外显子突变型为19DelK746~A750、19DelK745~E749和19DelK745~A750;21外显子突变类型分别为21L858R和21L861Q。EGFR突变主要发生在女性及不吸烟的患者中;且EGFR基因突变型者PFS明显优于野生型患者,χ2=11.287,P=0.001。以组织DNA检测为准,循环DNA中EGFR基因突变检测的特异性为97%,并且与组织DNA检测EGFR基因突变具有一定的一致性,Kappa=0.433。结论:血清循环DNA可用于EGFR基因突变检测,为肺癌靶向治疗提供实验依据。     

肺癌外周血EGFR突变检测及其临床意义

目的:通过血浆循环DNA的基因突变检测,筛选表皮生长因子受体(E-GFR)突变型肺癌患者,探讨突变特征及其在肺癌靶向治疗中的意义.方法:选取2009年9月至2010年5月苏州大学附属第一医院及上海市三甲类医院收治的96例肺癌患者的血浆以及其中59例相对应的肿瘤组织中提取DNA,采用PCR扩增和基因测序的方法检测EGFR基因的突变.结果:96例肺癌血样中检测出EGFR突变17例,其突变率为17.7%.在这些突变的样本中,外显子19和21突变分别占88.2%(15/17)和11.8%(2/17),其中直接测序法检测出EGFR纯合突变3例[L858R 2例,del E746-A750(1)1例],杂合突变14例.对14例杂合突变样本进一步通过单克隆基因测序法确定其突变类型为del E746-A750(2)9例、del E746-A750(1)3例、del L747-S752 2例.EGFR基因突变多见于肺腺癌(包括腺鳞癌)患者,与患者的性别与吸烟史无明显相关性.59例肺癌患者肿瘤组织的进一步分析证明,血浆EGFR基因突变类型与患者自身肿瘤的突变类型相同,表明血浆DNA检测到的EGFR突变与原发肿瘤检测到的突变相一致.结论:肺癌患者的血浆循环DNA与相对应的肿瘤组织DNA的EGFR基因突变类型一致;此外,相对于传统的"金标准"直接测序法而言,单克隆基因测序的方法能够更精确地判断基因的突变类型.这种简便且微创地检测血浆循环DNA的方法可应用于肺癌EG.FR基因突变的诊断,从而预测靶向治疗的疗效.     

中国非小细胞肺癌患者表皮生长因子受体基因突变的研究

目的:针对表皮生长因子受体(EGFR)的分子靶向治疗越来越受到国内外的广泛关注,其中EGFR酪氨酸激酶抑制剂(TKI)Gefitinib和Erlotinib已在中国上市,批准用于治疗晚期非小细胞肺癌(NSCLC).EGFR突变是靶向药物TKI治疗有效的一个预测指标.有关我国非小细胞肺癌患者EGFR基因突变的研究已有若干报道,本文意在探讨中国北方地区非小细胞肺癌患者表皮生长因子受体(EGFR)基因外显子18-21的突变特点.方法:收集50例来自北方地区的非小细胞肺癌患者的冰冻组织标本,进行EGFR基因外显子18-21的突变检测.结果:50例非小细胞肺癌组织中共检出突变15例(30%),其中外显子19突变6例,均为缺失突变del E746-A750,外显子21突变9 例 ,除1例为L861Q外, 其它均为 L858R替代突变 .女性患者的突变率( 12/23,52%)显著高于男性患者的突变率( 3/27 , 11%),P＝0.002 ;腺癌支气管肺泡癌患者的突变率( 13/26,50%)显著高于鳞癌患者的突变率( 2/20,10%),P=0.005;非吸烟者的突变率(10 /25,40%)高于吸烟者的突变率(5/25,20%),但无显著性差异,P=0.217.与其它报道比较,结果显示北方地区EGFR基因突变的总体发生率与其他地区无显著性差异 ,外显子19、20、21发生突变所占的比例除云南更常见于外显子19,有显著性差异(P＜0.05)外,与其他地区无显著性差异(P＞0.05).但北方地区突变的形式相对单一 .结论:中国南北方地区非小细胞肺癌患者EGFR基因突变发生率及主要突变类型基本一致,北方地区突变类型较单一,可给予针对性的检测.     

非小细胞肺癌表皮生长因子受体基因主要突变类型快速简便的检测方法

背景与目的:肺癌组织中表皮生长因子受体(epidermal growth factor receptor,EGFR)基因突变是靶向药物EGFR酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)治疗有效的一个重要相关因素及预测指标.目前临床上需要一种简单、敏感、可靠的方法来检测EGFR基因的突变,从而指导TKI类药物的最佳应用.本研究旨在进一步了解中国非小细胞肺癌(non-small cell lung cancer,NSCLC)患者EGFR基因突变的特点,并针对常见的特异性突变,寻找一种方便、准确、快捷的检测方法.方法:手术切除的NSCLC冰冻组织标本50例,对照为正常肺组织16例.分别提取肿瘤组织、正常肺组织DNA,PCR法扩增肿瘤组织DNA中EGFR基因外显子18～21,提纯后测序,确定有无突变存在.针对常见特异性突变设计突变特异引物,应用该引物扩增肿瘤组织及正常对照肺组织DNA,观察有无特异条带出现,并与直接测序结果相比较,观察是否存在一致性.结果:50例NSCLC组织中共检出突变15例,突变率30%,均为杂合子突变,其中外显子19突变的6例(12%),外显子21突变的9例(18%);外显子19的突变类型均为缺失突变del E746-A750;外显子21的突变类型为替代突变,8例为L858R,1例为L861Q.应用特异引物扩增已在直接测序中验证的存在特异突变的肺癌组织DNA,均显示出阳性条带;相反,对于16个正常对照肺组织DNA和在直接测序中未发现有突变的肺癌组织DNA,应用该特异引物扩增后,均无阳性条带出现.结论:本研究结果表明中国NSCLC患者EGFR基因突变的主要类型为外显子19的缺失突变和外显子21的替代突变,应用突变特异PCR检测肺癌组织中的常见EGFR基因突变类型,是一种简单、特异、准确、经济、省时省力的方法,可在临床中推广应用.     

PET/CT预测非小细胞肺癌表皮生长因子受体突变的研究进展

摘 要：表皮生长因子受体（epidermal growth factor receptor,EGFR）突变在肺癌的启动及进展中至关重要,EGFR酪氨酸激酶抑制剂能阻断这一过程,实现了对肺癌的靶向治疗。目前,EGFR酪氨酸激酶抑制剂的应用要通过基因检测明确EGFR基因状态,而临床实践及基因检测方法存在一些问题,导致基因检测结果不易获得。正电子发射计算机断层显像（PET/CT）已广泛应用于肿瘤诊断及治疗等方面,近年研究显示氟［18F］标记的氟代脱氧葡萄糖代谢参数、新型分子探针及影像组学可协助临床在无法获得基因情况时检测EGFR基因状态及对突变类型进行分类,实现精准治疗。全文就近年来应用PET/CT预测非小细胞肺癌中EGFR突变的研究进展进行综述。     

生物标志物指导下的非小细胞肺癌靶向治疗

 肺癌是最常见的恶性肿瘤之一。分子靶向治疗在21世纪非小细胞肺癌治疗中具有里程碑的意义。基于分子标志检测的靶向治疗更是为肺癌个体化治疗提供了坚实的基础。主要就EGFR突变检测在非小细胞肺癌个体化表皮生长因子受体酪氨酸激酶抑制（EGFR-TKI）一线、二线及维持治疗中的指导意义进行综述。同时介绍EGFR FISH检测在EGFR TKI治疗研究的现状、抗肿瘤血管药物潜在的分子预测标志以及抗EGFR单克隆抗体的个体化治疗现状。     

晚期肺癌血清游离DNA中EGFR外显子19的基因突变研究

目的分析晚期肺癌的上皮生长因子受体(epidermal growth factor receptor,EGFR)外显子19基因突变的类型及发生率。方法从血清中提取游离DNA进行EGFR外显子19特异性PCR扩增和基因测序。结果24例肺部良性疾病血样中EGFR基因外显子19均为野生型;而130例肺癌血样中检出突变55例,EGFR外显子19基因突变的检出率为42.3%。外显子19基因突变均为第746~752位密码子的碱基缺失,共有7种突变类型。外显子19基因突变主要见于肺腺癌及小细胞肺癌,其检出率分别为58.9%和57.1%,突变与患者年龄及性别无明显相关性。在肺癌的不同组织类型中,外显子19的突变形式存在显著差异,肺腺癌的基因突变谱与肺鳞癌、腺鳞癌及小细胞肺癌明显不同。结论晚期肺癌病人的血清游离DNA中存在EGFR基因突变,这类突变可以通过适当的方法检测出来,这种血液检测方法在晚期肺癌的EGFR基因诊断及靶向治疗中具有广泛的应用价值。     

Intratumor heterogeneity of epidermal growth factor receptor mutations in lung cancer and its correlation to the response to gefitinib

Somatic mutations introduced into the epidermal growth factor receptor (EGFR) gene in non-small-cell lung cancer (NSCLC) are important factors to determine therapeutic responses to gefitinib. The current diagnostic test measures the overall EGFR mutation status of the cancer tissue, and may ignore the presence of non-mutated, gefitinib-unresponsive cancer cells. Twenty-one NSCLC patients with EGFR mutations were recruited for the study. All patients were treated with gefitinib after surgical treatment. Fifty to sixty areas of NSCLC tumors were sampled from each tissue, and their EGFR mutation states were determined by a primer extension assay. This assay discriminates between EGFR mutation-positive and -negative cancer cells within a single tumor tissue. Fifteen tissues consisted only of cells with EGFR mutations, but the remaining six tissues contained both mutated and non-mutated cells. Time to disease progression and overall survival after gefitinib treatment were significantly shorter in those patients with EGFR heterogeneity ( P =  0.009 and P  = 0.003, respectively). A considerable proportion of NSCLC contains a heterogeneous population of both EGFR mutated and non-mutated cancer cells, resulting in a reduced response to gefitinib. The intratumor genetic heterogeneity of a target molecule such as EGFR would be an important factor to consider when treating patients with molecular target agents. ( Cancer Sci 2008; 99: 929–935)     

Increased epidermal growth factor receptor (EGFR) gene copy number is strongly associated with EGFR mutations and adenocarcinoma in non-small cell lung cancers: a chromogenic in situ hybridization study of 182 patients

SUMMARY: To evaluate the association of epidermal growth factor receptor (EGFR) gene copy number with EGFR and k-ras mutation status and tyrosine kinase inhibitor (TKI) sensitivity in non-small cell lung cancer (NSCLC), EGFR gene copy number of 182 NSCLC tumor specimens were analyzed by chromogenic in situ hybridization (CISH). EGFR and k-ras mutation analyses were also performed for, respectively, 176 and 157 of the 182 patients. Additionally, 36 patients in this study had received TKI monotherapy. The tumor was considered to be CISH positive if the gene copy number was >or=5 signals per nucleus in >or=40% of tumor cells. CISH-positive tumors were strongly associated with adenocarcinoma (56.8%) compared with squamous cell carcinoma (15.9%) (p<0.0001). The CISH-positive tumors were also strongly associated with EGFR mutations (78%) compared with wild type (20.2%) (p<0.0001). Only six tumors had k-ras mutations. None had EGFR mutation and only one was CISH positive. In the patients treated with TKI, EGFR mutation was strongly associated with TKI responsiveness (22/25 responders) (p<0.0001), but the CISH-positive tumors were only marginally significant (18/25 responders) (p=0.0665). Patients with EGFR mutations or CISH-positive tumors were all associated with longer median survival, although not statistically significant. Our results suggest Increased EGFR copy number was highly correlated with EGFR mutation in adenocarcinoma. Although it is less correlated with TKI responsiveness when compared with EGFR mutations, it still could be a good alternative molecular predictive marker for TKI responsiveness, since CISH can be done on paraffin section and is much quicker than DNA sequencing.     

Detection of epidermal growth factor receptor mutations in serum as a predictor of the response to gefitinib in patients with non-small-cell lung cancer.

Cases of non-small-cell lung cancer (NSCLC) carrying the somatic mutation of epidermal growth factor receptor (EGFR) have been shown to be hyperresponsive to the EGFR tyrosine kinase inhibitor gefitinib (IRESSA). If EGFR mutations can be observed in serum DNA, this could serve as a noninvasive source of information on the genotype of the original tumor cells that could influence treatment and the ability to predict patient response to gefitinib. Serum genomic DNA was obtained from Japanese patients with NSCLC before first-line gefitinib monotherapy. Scorpion Amplified Refractory Mutation System technology was used to detect EGFR mutations. Wild-type EGFR was detected in all of the 27 serum samples. EGFR mutations were detected in 13 of 27 (48.1%) patients and two major EGFR mutations were identified (E746_A750del and L858R). The EGFR mutations were seen significantly more frequently in patients with a partial response than in patients with stable disease or progressive disease (P = 0.046, Fisher's exact test). The median progression-free survival was significantly longer in patients with EGFR mutations than in patients without EGFR mutations (200 versus 46 days; P = 0.005, log-rank test). The median survival was 611 days in patients with EGFR mutations and 232 days in patients without EGFR mutations (P > 0.05). In pairs of tumor and serum samples obtained from 11 patients, the EGFR mutation status in the tumors was consistent with those in the serum of 8 of 11 (72.7%) of the paired samples. Thus, EGFR mutations were detectable using Scorpion Amplified Refractory Mutation System technology in serum DNA from patients with NSCLC. These results suggest that patients with EGFR mutations seem to have better outcomes with gefitinib treatment, in terms of progression-free survival, overall survival, and response, than those patients without EGFR mutations.     

肺腺癌患者外周血中外泌体EGFR突变检测及其临床意义北大核心

目的:探讨肺腺癌患者外周血中外泌体检测EGFR的临床意义。方法:采用PCR方法检测肺腺癌患者外周血中外泌体、ctDNA和癌组织中EGFR突变情况,分析肺腺癌患者外周血外泌体中EGFR突变及其与临床病理特征的关系,比较外周血中外泌体、ctDNA和癌组织中检测EGFR突变的一致性。结果:肺腺癌患者外周血外泌体中检测EGFR突变型肺腺癌21例,EGFR野生型肺腺癌23例。肺腺癌外泌体中EGFR突变与性别、年龄、肿瘤大小、TNM分期、组织学类型及淋巴结转移情况比较差异无统计学意义(P>0.05)。肺腺癌组织检测25例EGFR突变中,外泌体中检测出EGFR突变19例,一致率为76%;19例肺腺癌组织EGFR野生型中,外泌体检测出EGFR突变2例。25例肺腺癌组织EGFR突变中,ctDNA中检测出EGFR突变16例,一致率为64%。kappa分析显示,外泌体、ctDNA与癌组织检测一致性较好,前者一致性优于后者。结论:外泌体可用于肺腺癌血浆中EGFR突变检测,对指导临床用药具有一定意义。     

Ligand‐triggered resistance to molecular targeted drugs in lung cancer: Roles of hepatocyte growth factor and epidermal growth factor receptor ligands

Recent advances in molecular biology have led to the identification of new molecular targets, such as epidermal growth factor receptor ( EGFR ) mutations and echinoderm microtubule‐associated protein‐like 4 (EML4) – anaplastic lymphoma kinase (ALK) fusion gene, in lung cancer. Dramatic response has been achieved with EGFR inhibitors (gefitinib and erlotinib) and an ALK inhibitor (crizotinib) in lung cancer expressing corresponding targets. However, cancer cells acquire resistance to these drugs and cause recurrence. Known major mechanisms for resistance to molecular targeted drugs include gatekeeper mutations in the target gene and activation of bypass survival signal via receptors other than the target receptors. The latter mechanism can involve receptor gene amplification and ligand‐triggered receptor activation as well. For example, hepatocyte growth factor (HGF), the ligand of a tyrosine kinase receptor Met, activates Met and the downstream PI3K/Akt pathway and triggers resistance to EGFR inhibitors in EGFR mutant lung cancer cells. Moreover, EGFR ligands activate EGFR and downstream pathways and trigger resistance to crizotinib in EML4‐ALK lung cancer cells. These observations indicate that signals from oncogenic drivers (EGFR signaling in EGFR ‐mutant lung cancer and ALK signaling in EML4‐ALK lung cancer) and ligand‐triggered bypass signals (HGF‐Met and EGFR ligands‐EGFR, respectively) must be simultaneously blocked to avoid the resistance. This review focuses specifically on receptor activation by ligand stimulation and discusses novel therapeutic strategies that are under development for overcoming resistance to molecular targeted drugs in lung cancer. (Cancer Sci 2012; 103: 1189–1194)     

Epidermal growth factor receptor and K-Ras in non-small cell lung cancer-molecular pathways involved and targeted therapies

Lung cancer is currently the leading cause of cancer death in Western nations. Non-small cell lung cancer (NSCLC) represents 80% of all lung cancers, and adenocarcinoma is the predominant histological type. Despite the intensive research carried out on this field and therapeutic advances, the overall prognosis of these patients remains unsatisfactory, with a 5-year overall survival rate of less than 15%. Nowadays, pharmacogenetics and pharmacogenomics represent the key to successful treatment. Recent studies suggest the existence of two distinct molecular pathways in the carcinogenesis of lung adenocarcinoma: one associated with smoking and activation of the K-Ras oncogene and the other not associated with smoking and activation of the epidermal growth factor receptor (EGFR). The K-ras mutation is mainly responsible for primary resistance to new molecules which inhibit tyrosine kinase EGFR (erlotinib and gefitinib) and most of the EGFR mutations are responsible for increased tumor sensitivity to these drugs. This article aims to conduct a systematic review of the literature regarding the molecular pathways involving the EGFR, K-Ras and EGFR targeted therapies in NSCLC tumor behavior.     

Defining clinically relevant molecular subsets of lung cancer

The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), gefitinib and erlotinib, induce dramatic responses in certain patients with non-small cell lung cancer (NSCLC). As such, the drugs provide an unexpected tool to dissect clinically relevant molecular subsets of NSCLC. For example, using mutational profiling of tumor DNA from patients with sensitivity, primary resistance, and secondary resistance to these agents, we and others have demonstrated that somatic mutations in the tyrosine kinase domain of EGFR are associated with sensitivity to gefitinib and erlotinib, while mutations in KRAS, which encodes a GTPase downstream of EGFR, are associated with primary resistance. Furthermore, second site mutations in the EGFR kinase domain are commonly found in patients with acquired resistance. We are now using a variety of molecular and biological approaches to help further define molecular subsets of lung cancer that have relevance in the clinic.     

EGFR Mutation status in Japanese lung cancer patients: genotyping analysis using LightCycler.

PURPOSE: Recently, somatic mutations of the epidermal growth factor receptor (EGFR) gene were found in approximately 25% of Japanese lung cancer patients. These EGFR mutations are reported to be correlated with clinical response to gefitinib therapy. However, DNA sequencing using the PCR methods described to date is time-consuming and requires significant quantities of DNA; thus, this existing approach is not suitable for a routine pretherapeutic screening program. EXPERIMENTAL DESIGN: We have genotyped EGFR mutation status in Japanese lung cancer patients, including 102 surgically treated lung cancer cases from Nagoya City University Hospital and 16 gefitinib-treated lung cancer cases from Kinki-chuo Chest Medical Center. The presence or absence of three common EGFR mutations were analyzed by real-time quantitative PCR with mutation-specific sensor and anchor probes. RESULTS: In exon 21, EGFR mutations (CTG --> CGG; L858R) were found from 8 of 102 patients from Nagoya and 1 of 16 from Kinki. We also detected the deletion mutations in exon 19 from 7 of 102 patients from Nagoya (all were deletion type 1a) and 4 of 16 patients from Kinki (one was type 1a and three were type 1b). In exon 18, one example of G719S mutation was found from both Nagoya and Kinki. The L858R mutation was significantly correlated with gender (women versus men, P < 0.0001), Brinkman index (600 < or = versus 600, P = 0.001), pathologic subtypes (adenocarcinoma versus nonadenocarcinoma, P = 0.007), and differentiation status of the lung cancers (well versus moderately or poorly, P = 0.0439), whereas the deletion mutants were not. EGFR gene status, including the type of EGFR somatic mutation, was correlated with sensitivity to gefitinib therapy. For example, some of our gefitinib-responsive patients had L858R or deletion type 1a mutations. On the other hand, one of our gefitinib-resistant patients had a G719S mutation. CONCLUSIONS: Using the LightCycler PCR assay, the EGFR L858R mutation status might correlate with gender, pathologic subtypes, and gefitinib sensitivity of lung cancers. However, further genotyping studies are needed to confirm the mechanisms of EGFR mutations for the sensitivity or resistance of gefitinib therapy for the lung cancer.     

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

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。