EGFR基因突变NSCLC脑转移瘤放疗联合TKI研究现状

非小细胞肺癌(NSCLC)脑转移的患者预后较差,酪氨酸酶抑制剂(TKI)显著改善了表皮生长因子受体(EGFR)基因敏感突变患者的预后。EGFR敏感突变与NSCLC的脑转移发生率相关并可能影响其放疗和药物治疗疗效,脑转移瘤的EGFR-TKI单药治疗和放疗均有效,二者联合是否较单一治疗改善EGFR基因突变的NSCLC脑转移...     

非小细胞肺癌EGFR-TKI耐药的分子机制及防治策略

目的 近年来EGFR酪氨酸激酶抑制剂(epidermal growth factor receptor tyrosine kinase inhibitor,EGFR-TKI)是EGFR突变型晚期NSCLC的重要治疗手段之一,然而,绝大部分患者治疗9～13个月后即出现耐药.EGFR-TKIs的耐药机制和耐药后治疗策略已成为基础和临床研究的热点.探讨非小细胞肺癌中表皮生长因子受体酪氨酸激酶抑制剂(epithelial growth factor receptor tyrosine kinase inhibitor,EGFR-TKI)耐药的分子机制及防治策略.方法 应用Pubmed和CNKI期刊全文数据库检索系统,以“EGFR TKI和耐药”为关键词,检索2005-01-2016-05的相关文献.纳入标准:(1) EGFR TKI耐药的定义;(2)EGFR-TKI的耐药分类;(3)EGFR-TKI耐药的分子机制;(4) EGFR-TKI耐药的防治策略.纳入57篇文献进行分析.结果 EGFR TKI耐药分为原发性耐药和获得性耐药.原发性耐药机制包括不同EGFR突变位点的敏感性差异和KRAS突变等,获得性耐药机制包括T790M突变、EGFR下游信号分子活化、旁路激活及表型转化等.耐药后仍缺乏标准治疗策略,可继续EGFR-TKI治疗、EGFR-TKI联合化疗或其他靶向治疗或改为化疗;基于耐药靶点的治疗策略,如第三代EGFR-TKI、Met抑制剂等也可作为选择.结论 EGFR-TKI耐药机制复杂,缺乏标准耐药治疗策略,基于临床治疗模式和耐药靶点的治疗策略有望为EGFR-TKI耐药患者的个体化治疗提供思路.     

Concurrent Genetic Alterations Predict the Progression to Target Therapy in EGFR-Mutated Advanced NSCLC

Introduction

EGFR-mutant NSCLC displays diverse outcomes to tyrosine kinase inhibitor (TKI) treatment. Because co-occurring genomic alterations might describe different biological subsets of patients with this cancer, exploring co-occurring genomic alterations that impact patients’ outcomes using a comprehensive gene panel is potentially important.

EGFR mutation frequency and effectiveness of erlotinib: A prospective observational study in Danish patients with non-small cell lung cancer

Objectives

In 2008, we initiated a prospective study to explore the frequency and predictive value of epidermal growth factor receptor (EGFR) mutations in an unselected population of Danish patients with non-small cell lung cancer offered treatment with erlotinib, mainly in second-line.

Materials and methods

Four hundred and eighty eight patients with advanced NSCLC were included. The mutation status was assessed using the cobas^® EGFR Mutation Test. Erlotinib was administrated (150 mg/d) until disease progression or unacceptable toxicities occurred. The primary endpoint was progression-free survival. Secondary endpoints were overall survival and response.

Results

Biopsies were retrieved from 467 patients, and mutation results obtained for 462. We identified 57 (12%) patients with EGFR mutations: 33 exon 19 deletions, 13 exon 21 mutations, 5 exon 18 mutations, 3 exon 20 insertions, 1 exon 20 point mutation (S768I), and two complex mutations. Seven percent of the patients were never smokers. The differences in median progression-free survival and overall survival between the mutated group and the wild-type group were 8.0 vs. 2.5 months, p < 0.001 and 12.1 vs. 3.9 months, p < 0.001. Performance status (0–1 vs. 2–3) and line of treatment (1st vs. 2nd and 3rd) had no influence on outcome in EGFR-mutated patients.

Conclusion

We found a higher frequency of EGFR mutations than expected in a cohort with less than 10% never smokers. The outcome after treatment with erlotinib was much better in patients with EGFR mutations than in patients with wild-type EGFR and was independent of performance status and treatment line in EGFR-mutated patients.     

EGFR-TKI一线治疗EGFR基因突变的晚期非小细胞肺癌临床观察

背景与目的研究表明,一线表皮生长因子受体酪氨酸激酶抑制剂(epidermal growth factor receptortyrosine kinase inhibitor,EGFR-TKI)治疗晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)的客观缓解率及无进展生存期明显优于铂二联的化疗,且耐受性更好。本研究旨在分析EGFR-TKI一线治疗晚期EGFR突变阳性的NSCLC患者的疗效与耐受性。方法 54例晚期NSCLC患者肿瘤标本采用直接测序法证实EGFR活化突变(外显子19缺失或外显子21点突变),一线给予EGFR-TKI口服治疗直至疾病进展,观察疗效及不良反应,并进行生存随访。结果 54例患者外显子19缺失33例(61%),外显子21点突变21例(39%)。均一线接受EGFR-TKI治疗,总体缓解率为90%,中位无进展生存期(progression free survival,PFS)为8.3个月,中位生存期为19.5个月;外显子19缺失患者的中位PFS(9.0个月)较21点突变(7.0个月)时间长(P=0.002)。外显子19缺失患者的中位总生存期(overall survival,OS)(25.0个月)较21点突变(16.0个月)时间长(P=0.001);吉非替尼与厄洛替尼疗效相当,但吉非替尼组安全性更好;最常见的不良事件为皮疹和腹泻,有2例患者(4%)出现了3度皮肤毒性反应,2例患者(4%)出现了3度的转氨酶升高,1例患者(1%)出现了3度口腔炎。结论存在EGFR基因突变的晚期NSCLC患者一线接受EGFR-TKI治疗安全有效,且外显子19缺失比L858R突变疗效更优。     

Effect of EGFR-TKI retreatment following chemotherapy for advanced non-small cell lung cancer patients who underwent EGFR-TKI

Objective： Non-small cell lung cancer （NSCLC） patients with epidermal growth factor receptor （EGFR）-activating mutations have higher response rate and more prolonged survival following treatment with single-agent EGFR tyrosine kinase inhibitor （EGFR-TKI） compared with patients with wild-type EGFR. However, all patients treated with reversible inhibitors develop acquired resistance over time. The mechanisms of resistance are complicated. The lack of established therapeutic options for patients after a failed EGFR-TKI treatment poses a great challenge to physicians in managing this group of lung cancer patients. This study evaluates the influence of EGFR-TKI retreatment following chemotherapy after failure of initial EGFR-TKI within at least 6 months on NSCLC patients. Methods： ＇i-he data of 27 patients who experienced treatment failure from their initial use of EGFR-TKI within at least 6 months were analyzed. After chemotherapy, the patients were retreated with EGFR-TKI （gefitinib 250 mg qd or erlotinib 150 mg qd）, and the tumor progression was observed. The patients were assessed for adverse events and response to therapy. Targeted tumor lesions were assessed with CT scan. Results： Of the 27 patients who received EGFR-TKI retreatment~ 1 （3.7%） patient was observed in complete response （CR）, 8 （29.6%） patients in partial response （PR）, 14 （51.9%） patients in stable disease （SD）, and 4 （14.8%） patients in progressive disease （PD）. The disease control rate （DCR） was 85.2% （95% CI： 62%-94%）. The median progression-free survival （mPFS） was 6 months （95% CI： 1-29）. Of the 13 patients who received the same EGFR-TKI, 1 patient in CR, 3 patients in PR, 8 patients in SD, and 2 patients in PD were observed. The DCRwas 84.6%, and the mPFS was 5 months. Of the 14 patients who received another EGFR-TKI, no patient in CR~ 6 patients in PR, 6 patients in SD, and 2 patients in PD were observed. The DCRwas 85.7%, and the mPFS was 9.5 months. Significant di     

EGFR-TKI治疗肺腺癌疗效与胸部CT特征相关性研究

背景与目的许多研究结果证明:应用表皮细胞生长因子受体酪氨酸激酶抑制剂(EGFR-TKI)吉非替尼(gefitinib)和埃罗替尼(erlotinib)治疗非小细胞肺癌对非吸烟的肺腺癌患者疗效较高。本研究旨在探讨EGFR-TKI治疗肺腺癌的疗效与胸部X线CT表现之间的关系。方法分析2004年1月1日至2007年3月31日期间在北京协和医院肿瘤内科门诊和住院的含铂方案治疗后进展的晚期肺腺癌患者37例,男20例,女17例,年龄54-85岁(平均67.5岁)。给予吉非替尼250mg或者埃罗替尼150mg,每日一次口服,持续用药至病情进展。每2个月进行胸部增强CT扫描并随访,参照RECIST疗效评价标准进行评估,同时对病变CT特点进行分析。结果本组应用吉非替尼治疗28例,埃罗替尼治疗9例,其中治疗受益者21例,包括部分缓解7例,稳定14例,无完全缓解病例,进展16例。CT特征分析表明,胸内转移灶在3个以上或者弥漫性病变者受益率占79.9%(15/19),1-2个结节病灶受益率占33.3%(6/18),两者比较具有统计学意义。P<0.05。有胸腔积液者受益率占73.1%(19/26),无胸腔积液者受益率为22.2%(2/9),P<0.05。增强CT扫描可分析的21名患者结节共70个,中等以上强化的结节治疗后病变好转率67.4%(31/46),无强化者好转率37.5%(9/24),P<0.05。而性别、肿瘤大于3cm和病灶边缘光滑与否与疗效之间的关系无统计学差异(P>0.05)。受益组与进展组比较中位生存期无统计学差异。Cox回归分析表明影像学表现不能成为独立预后因素(总HR值为0.766,P>0.05)。结论EGFR-TKI治疗肺腺癌,CT表现为多发转移或弥漫性病变、胸腔积液和局部病灶中等增强者治疗受益率高,这些指标对疗效有一定疗效预测作用,但与预后的关系尚待探讨。     

Erlotinib usage after prior treatment with gefitinib in advanced non-small cell lung cancer: A clinical perspective and review of published literature

Erlotinib and gefitinib are among the most widely researched, used and available molecularly targeted therapies for treatment of advanced non-small cell lung cancer (NSCLC). They are both tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR). In the past decade, there have been reports on clinical benefit from use of erlotinib after gefitinib failure in NSCLC patients. A review of published literature on this focussed topic is provided herein. Pooled analysis of published literature shows that majority of patients were female (60.6%), non-smokers (64.5%), had adenocarcinoma histology (88.3%) and were of East Asian ethnicity (92.3%). Presence of sensitizing EGFR mutation was detected in 48.4% of subjects. Disease control rates with prior gefitinib therapy and with subsequent erlotinib treatment were 79.4% and 45.4% respectively. Based upon our review, the most important predictive factor for clinical benefit from erlotinib identified was previous response to gefitinib. The exact explanations for the potential benefit from erlotinib use in this patient population is still not known and further studies are required to determine the role of molecular mechanisms especially those related to resistance to initial EGFR TKI therapy.     

EGFR-TKI治疗对NSCLC患者血清CEA的影响

目的 探讨表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKI)治疗对非小细胞肺癌(NSCLC)患者血清癌胚抗原(CEA)的影响.方法 选取NSCLC患者81例,均接受EGFR-TKI治疗,监测患者治疗前后的CEA水平.结果 完全缓解(CR)+部分缓解(PR)患者治疗后的CEA水平低于治疗前(P﹤0.05);进展(PD)患者治疗后的CEA水平高于治疗前(P﹤0.05);稳定(SD)患者治疗前后的CEA水平比较,差异无统计学意义(P﹥0.05);CR+PR患者治疗前的CEA水平高于SD和PD患者(P﹤0.05);不同年龄、性别、吸烟史、组织类型、临床分期和治疗药物的NSCLC患者的近期疗效比较,差异无统计学意义(P﹥0.05);基线CEA≥5 ng/ml患者的近期疗效优于基线CEA﹤5 ng/ml的患者(P﹤0.05);基线CEA≥5 ng/ml组患者的中位无疾病进展时间为16.61个月(95%CI:12.22~20.43个月),长于基线CEA﹤5 ng/ml组患者的9.82个月(95%CI:5.21~14.40个月)(P﹤0.05).结论 血清CEA监测有助于判断NSCLC患者EGFR-TKI治疗效果,CEA治疗前高水平可能预示靶向药物治疗效果好.     

Phase II Study of the EGFR-TKI Rechallenge With Afatinib in Patients With Advanced NSCLC Harboring Sensitive EGFR Mutation Without T790M: Okayama Lung Cancer Study Group Trial OLCSG 1403

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) as first-line therapy for patients with EGFR-mutated non–small-cell lung cancer (NSCLC) have shown a significantly better objective response rate and progression-free survival than platinum doublet therapy. However, acquired resistance often occurs within 12 months. One of the potential strategies for treating acquired resistance in NSCLC is the readministration of EGFR-TKIs, a strategy that has mainly been evaluated using gefitinib or erlotinib. The aim of the present study is to investigate the efficacy and safety of EGFR-TKI readministration with afatinib in patients with advanced NSCLC harboring activating EGFR mutations without T790M. The primary endpoint is progression-free survival. The secondary endpoints include the objective response rate, disease control rate, overall survival, toxicity, and quality of life. A total of 12 patients will be enrolled in this trial.     

Clinical implications of T790M mutation in patients with acquired resistance to EGFR tyrosine kinase inhibitors

Objectives

Although T790M mutation is considered to be the major mechanism of acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in patients with non-small cell lung cancer (NSCLC), its clinical implication remains undetermined.

Methods

Post-progression tumor specimens were prospectively collected for T790M mutation analysis in NSCLC patients with acquired resistance to initial EGFR TKIs. Clinical features were compared between patients with and without T790M.

Results

Out of 70 cases, 36 (51%) were identified to have T790M mutation in the rebiopsy specimen. There was no difference in the pattern of disease progression, progression-free survival for initial TKIs (12.8 and 11.3 months), post-progression survival (14.7 and 14.1 months), or overall survival (43.5 and 36.8 months) in patients with and without T790M. In total, 34 patients received afatinib after post-progression biopsy as a subsequent treatment, and the response rate was 18%. The median progression-free survival for afatinib was 3.7 months for the entire group, and 3.2 and 4.6 months for the groups with and without T790M, respectively (P = 0.33).

Conclusions

The identification of T790M as acquired resistance mechanism was clinically feasible. Although T790M had no prognostic or predictive role in the present study, further research is necessary to identify patients with T790M-mutant tumors who might benefit from newly developed T790M-specific TKIs.     

Tumor resensitization to erlotinib following brief substitution of cetuximab

Targeted inhibition of epidermal growth factor receptors (EGFR) is becoming a standard anticancer treatment in defined clinical scenarios. EGFR inhibition may be achieved either by small-molecule orally bioavailable tyrosine kinase inhibitors, such as gefitinib or erlotinib, or else by large-molecule receptor antibodies, such as cetuximab or panitumumab. Here, we describe a case of pancreatic cancer in which the small-molecule EGFR antagonist erlotinib was used before and after the EGFR antibody cetuximab, with unexpected potentiation of both toxic and therapeutic sequelae.     

Efficacy of chemotherapy in epidermal growth factor receptor (EGFR) mutated metastatic pulmonary adenocarcinoma patients who had acquired resistance to first-line EGFR tyrosine kinase inhibitor (TKI)

Introduction: Salvage chemotherapy is frequently used when tumour epidermal growth factor receptor (EGFR) mutated patients experience disease progression with first-line EGFR-tyrosine kinase inhibitor (TKI) treatment. However, the efficacy of salvage chemotherapy is still unknown.

Methods: We retrospectively reviewed the chart records of our pulmonary adenocarcinoma patients between 2010 and 2013.

Results: Five hundred and six of the 1240 stage IV adenocarcinoma patients had an EGFR mutation and 338 received first-line EGFR-TKI treatment. In all, 169 patients in this group received salvage chemotherapy after failure of EGFR-TKI, and 102 patients were eligible for this study. The chemotherapy response rate of these 102 patients was 24.5%, with a median progression-free survival (PFS) of 4.5?months, and median survival time was 14.6?months. Patients who received pemetrexed-based chemotherapy had longer PFS and overall survival (OS), although the extent was statistically insignificant. Progression-free survival and OS were longer for patients who received combination chemotherapy than single-agent chemotherapy.

Conclusions: Pemetrexed-based combination chemotherapy is preferred before a more efficient treatment strategy is found.     

Concurrence of EGFR amplification and sensitizing mutations indicate a better survival benefit from EGFR-TKI therapy in lung adenocarcinoma patients

ObjectivesTumor heterogeneity, which causes different EGFR mutation abundance, is believed to be responsible for varied progression-free survival (PFS) in lung adenocarcinoma (ADC) patients receiving EGFR-TKI treatment. Frequent EGFR amplification and its common affection in EGFR mutant allele promote the hypothesis that EGFR mutant abundance might be determined by EGFR copy number variation and therefore examination of EGFR amplification status in EGFR mutant patients could predict the efficacy of EGFR-TKI treatment.Materials and methodsIn this study, 86 lung ADC patients, who harbored EGFR activating mutations and received EGFR-TKI treatment, were examined for EGFR amplification and expression by Dual-color Silver in situ Hybridization (DISH) and immunohistochemistry analysis, respectively.Results and conclusionForty-one of 86 (47.7%) samples with EGFR activating mutations were identified with EGFR amplification. Patients with EGFR gene amplification had a significantly longer PFS than those without (16.3 vs. 9.1 months, p = 0.004). The EGFR expression was then examined by immunohistochemistry analysis. Thirty-nine of 86 (45%) tumors had EGFR overexpression, which was significantly correlated with EGFR amplification (p = 0.000). However, patients with EGFR overexpression exhibited no difference in PFS (14.1 vs. 13.3 months, p = 0.797). In conclusion, EGFR amplification occurs frequently in lung ADC patients harboring EGFR activating mutations, and could serve as an indicator for better response from EGFR-TKI treatment.     

miRNAs与非小细胞肺癌EGFR突变及放疗相关性研究进展

EGFR作为NSCLC靶向治疗的热点,近年来其在分子生物学水平的研究众多。而放疗作为一种NSCLC重要的传统治疗方法,其疗效与EGFR突变及过表达相关。放疗联合EGFR-TKI在NSCLC治疗上的疗效还缺乏Ⅲ期临床结果。miRNAs能够调控肿瘤相关基因表达,影响肿瘤生物学活动。近来研究显示miRNAs对EGFR突变、EGFR-TKI和放疗均存在正向或负向的调控作用,其具体机制已部分阐明。现就miRNAs对EGFR突变、EGFR-TKI及放疗间相关性作一综述,旨在为miRNAs应用于放疗联合EGFR-TKI治疗NSCLC提供最新诊疗依据。     

Afatinib in the treatment of EGFR mutation-positive NSCLC – A network meta-analysis

Objectives

Epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer (NSCLC) is a specific lung cancer subtype characterized by sensitivity to treatment with EGFR tyrosine kinase inhibitors (TKIs). Two reversible EGFR TKIs (gefitinib, erlotinib) and the irreversible ErbB family blocker afatinib are currently approved for treatment of EGFR mutation-positive NSCLC, but no head-to-head trials have been reported to date. We aimed to assess the relative efficacy of the three drugs by conducting a network meta-analysis (NMA).

Materials and methods

A systematic literature review was conducted to identify all the available evidence. Outcomes of interest were progression-free survival (PFS) and overall survival. For PFS, results by investigator review were considered as not all trials assessed PFS independently. Results were analyzed using Bayesian methods.

Results

The literature search identified 246 articles that were assessed for eligibility, of which 21 studies were included in the NMA, including eight trials performed in an EGFR mutation-positive population. The estimated PFS HR (95% credible interval, CrI) for afatinib compared with gefitinib was 0.70 (0.40–1.16) and compared with erlotinib was 0.86 (0.50–1.50) in the total population. The estimated probability of being best for afatinib over all other treatments for PFS was 70% versus 27% for erlotinib and 3% for gefitinib; the estimated probability of chemotherapy being the best treatment was 0%. Estimated HR (95% CrI) in patients with common mutations was 0.73 (0.42–1.24) for afatinib compared with erlotinib and 0.60 (0.34–0.99) for afatinib compared with gefitinib. OS findings were not significantly different between treatments.

Conclusions

In the absence of direct head-to-head trial data comparing efficacy between the three EGFR TKIs, our analysis suggests that afatinib is a viable treatment alternative to erlotinib or gefitinib in terms of PFS. A direct trial-based comparison of the efficacy of these agents is warranted to clarify their relative benefits.     

Bevacizumab and erlotinib: a promising new approach to the treatment of advanced NSCLC

Biologic agents that target molecules involved in tumor growth, progression, and pathological angiogenesis--such as the human epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF)--have demonstrated efficacy in patients with non-small cell lung cancer (NSCLC). Erlotinib (Tarceva); OSI Pharmaceuticals, Inc., Melville, NY, Genentech, Inc., South San Francisco, CA, and F. Hoffmann-La Roche Ltd, Basel, Switzerland), a highly selective tyrosine kinase inhibitor that inhibits EGFR, and bevacizumab (Avastin); Genentech, Inc., South San Francisco, CA, and F. Hoffmann-La Roche Ltd, Basel, Switzerland), a VEGF-targeted recombinant humanized monoclonal antibody, have displayed very encouraging activity in a randomized phase II trial in patients with previously treated NSCLC. Because erlotinib and bevacizumab act on two different pathways critical to tumor growth and dissemination, administering these drugs concomitantly may confer additional clinical benefits to cancer patients with advanced disease, by virtue of their complementary (or additive) antitumor activity. The combination of bevacizumab plus erlotinib may prove to be a viable second-line alternative to chemotherapy or erlotinib monotherapy in patients with NSCLC. The benefits of the combination may be further enhanced by selecting for patients who are likely to respond to this therapy. While a number of potential predictive markers have been identified for erlotinib, their value remains to be confirmed in prospective trials. In addition, the application of such personalized therapy will also depend on the availability of validated screening methods.