Frequency of EGFR mutations in Greek non-small-cell lung cancer (NSCLC) patients.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e21141-e21141
Author(s):  
Samuel Murray ◽  
Eirini Papadopoulou ◽  
George Nasioulas

e21141 Background: NSCLC patients harboring activating somatic mutations within the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) significantly benefit from EGFR targeted therapy. Treatment with the recently approved EGFR inhibitor IRESSA (gefitinib) leads to improved response and survival outcomes, therefore screening for EGFR mutations has entered routine clinical practice. Several clinico-pathological factors correlate with these mutations including gender, smoking history, and histology. The frequency of EGFR mutations is also ethnicity-dependent, wherein the incidence in Asian populations is ~30%, while in Caucasians (Whites) it is lower, ~ 15%. However, limited data is available on intra-ethnic differences throughout Europe. Aim: The aim of this study was to determine the frequency and spectrum of EGFR mutations in an unselected group of Greek NSCLC patients and investigate technical aspects of analysis. Methods: We set up High Resolution Melting Analysis (HRMA) assays to identify mutations in exons 18-21 of the EGFR gene and validated their analytical sensitivity by making serial dilutions of samples with known mutations and tumor cell content (TCC). A total of 698 NSCLC patients were screened with HRMA for somatic EGFR mutations in exons 18-21 and mutation status was verified by bi-directional sequencing. Pathological review was obtained for all samples and macro-dissection was used to ensure a %TCC of >75% in all possible cases. Results: The sensitivity of our HRM assays was found to be ≤1.5% Using HRMA and bi-directional sequencing a frequency of 19.05% was obtained; 105 x exon 19, 21 x exon 21, 6 x exon 20 and 1 x exon 18 . Conclusions: Applying a very sensitive mutation detection technique in a large cohort of unselected Greek NSCLC patients in routine diagnostic practice, we obtained an overall mutation frequency of 19.05%. This mutation frequency is similar to that found by the SLADB and EURTAC studies in European populations. Differences in sensitivity between techniques suggest that more than one technique should be advised in routine diagnostic practice.

2007 ◽  
Vol 22 (1_suppl4) ◽  
pp. 10-23 ◽  
Author(s):  
F. Cappuzzo ◽  
L. Toschi ◽  
G. Finocchiaro ◽  
C. Ligorio ◽  
A. Santoro

The epidermal growth factor receptor (EGFR) plays a key role in cancer development and progression in several human malignancies including non-small cell lung cancer (NSCLC). Several strategies aimed at inhibiting the EGFR have been investigated in the last years, including the use of small tyrosine kinase inhibitors (TKIs) directed against the intracellular domain of the receptor and monoclonal antibodies targeting its extracellular portion. Subgroups of patients who are more likely to respond to TKIs have been identified based on both clincal and biological features. Never-smoking history has emerged as the most relevant clinical characteristic predictive of response to TKIs in NSCLC, while presence of drug-sensitive EGFR mutations and EGFR gene gain represent critical biological variables associated with an improved outcome for patients exposed to these agents. Recent studies have highlighted the existence of biological factors involved in intrinsic and acquired resistance to TKIs, including k-ras, HER-2 and EGFR exon 20 mutations. Increasing knowledge of EGFR biology and drug-receptor interactions will allow to identify individuals who are likely to derive a clinical benefit from the proposed targeted therapy, sparing refractory patients expensive and potentially toxic treatment.


2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e18021-e18021
Author(s):  
Nicola Normanno ◽  
Carmine Pinto ◽  
Gian Luigi Taddei ◽  
Giancarlo Troncone ◽  
Paolo Graziano ◽  
...  

e18021 Background: Gefitinib was approved in Italy for treatment of pts with advanced NSCLC carrying mutant EGFR in May 2010. Methods: The EGFR FASTnet program was designed to facilitate the exchange of biological material, clinico-pathological data and reports between medical oncologists, primary pathologists and referral laboratories. EGFR mutational analysis was carried by Sanger sequencing, Real Time PCR, Pyrosequencing, Fragment Analysis and High resolution melting. The Italian Association of Medical Oncology (AIOM) and the Italian Society of Surgical Pathology and Cytopathology (SIAPEC-IAP) have full access to the anonymous EGFR FASTnet database. Results: As of December 31, 2011, 503 oncologists, 135 pathologists and 38 referral laboratories joined the EGFR FASTnet program. The enrolled cohort of 3819 pts with advanced NSCLC was significantly enriched for adenocarcinoma histology (3172 [83%]), female sex (1361 [36%]) and smoking history (never smoker 911 [24%], former smoker>15 yrs 880 [23%], light smoker 194 [5%]). Mutational analysis was feasible in 3567 pts (93%). At registration, 72% of the pts had not received yet treatment for advanced disease. Mutational analysis was carried by Sanger sequencing in 2021 cases (57%), Real Time PCR in 174 (5%), Pyrosequencing in 636 (18%) and other techniques in 736 (21%). EGFR mutations were found in 520 cases (14.6%): 334 in exon 19 (9.4%), 163 in exon 21 (4.6%), 7 in exon 18 (0.2%) and 16 in exon 20 (0.4%). Proportion of mutated cases was slightly higher with Real time PCR compared to other techniques: Sanger 14.8%, Real time PCR 21.3%, Pyrosequencing 13.5%, other 13.3% (p = 0.049). A higher mutation rate was found in never smokers (32.0%), light smokers (18.7%) and former smokers >15 yrs (12.4%), as well as in adenocarcinoma (15.7%) and females (25.2%). Conclusions: The pts for EGFR mutational screening are spontaneously selected by medical oncologists according to known predictive factors. The results of the mutational analysis from clinical practice in Italy are consistent with data from literature.


Author(s):  
Leiming Xia ◽  
Lu Wen ◽  
Siying Wang

: EGFR-TKIs are facing a big challenge of everlasting activated EGFR mutations which lack of effective binding sites, this barrier confers the dark sides that largely limited the outcome of NSCLC patients in clinic. Combination strategies show impressive anti-tumor efficacy comparing with EGFR-TKI mono-treatment, especially targeting both stem cells and non-stem cells. SHP2 (Src homology 2-containing phosphotyrosine phosphatase 2) plays an important role in regulating various malignant biology through hyper-activating intracellular pathways due to either over expression or catalytical mutation. Some pathways that SHP2 involved in were overlaps with EGFR downstream, and others were not subject to EGFR. Interestingly, SHP2 suppression was reported that can destroy the stemness of cancer. Therefore, we hypothesize SHP2 inhibitor might be an promising drug that could synergistically enhance or sensitize the anti-tumor efficacy of EGFR-TKIs in EGFR mutated NSCLC patients. Here, we summarized the mechanisms of SHP2 in regulating EGFR mutated NSCLC patients, attempted to reveal the potential synergistic effects of SHP2 inhibitor combined with EGFR-TKIs.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Fangfang Lv ◽  
Liang Sun ◽  
Qiuping Yang ◽  
Zheng Pan ◽  
Yuhua Zhang

Background. Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is inevitable in EGFR-mutant non-small-cell lung cancer (NSCLC) patients. A germline 2903 bp deletion polymorphism of Bcl-2-like protein 11 (BIM) causes reduced expression of proapoptotic BH3-only BIM protein and blocks TKI-induced apoptosis of tumor cells. Yet the association between the deletion polymorphism and response to EGFR-TKI treatment remains inconsistent among clinical observations. Thus, we performed the present meta-analysis. Methods. Eligible studies were identified by searching PubMed, Embase, and ClinicalTrials.gov databases prior to March 31, 2021. Hazard ratios (HRs) and 95% confidence intervals (CIs) of progression-free survival (PFS) and overall survival (OS) and odds ratios (ORs) and 95% CIs of objective response rate (ORR) and disease control rate (DCR) were calculated by using a random effects model. Sensitivity, metaregression, and publication bias analyses were also performed. Results. A total of 20 datasets (3003 EGFR-mutant NSCLC patients receiving EGFR-TKIs from 18 studies) were included. There were 475 (15.8%) patients having the 2903-bp intron deletion of BIM and 2528 (84.2%) wild-type patients. BIM deletion predicted significantly shorter PFS ( HR = 1.35 , 95% CI: 1.10-1.64, P = 0.003 ) and a tendency toward an unfavorable OS ( HR = 1.22 , 95% CI: 0.99-1.50, P = 0.068 ). Patients with deletion polymorphism had lower ORR ( OR = 0.60 , 95% CI: 0.42-0.85, P = 0.004 ) and DCR ( OR = 0.59 , 95% CI: 0.38-0.90, P = 0.014 ) compared with those without deletion. Conclusion. BIM deletion polymorphism may confer resistance to EGFR-TKIs and can be used as a biomarker to predict treatment response to EGFR-TKIs in EGFR-mutant NSCLC patients from Asian populations.


2006 ◽  
Vol 24 (11) ◽  
pp. 1700-1704 ◽  
Author(s):  
DuyKhanh Pham ◽  
Mark G. Kris ◽  
Gregory J. Riely ◽  
Inderpal S. Sarkaria ◽  
Tiffani McDonough ◽  
...  

Purpose Lung adenocarcinomas with mutations in exons 19 and 21 of the epidermal growth factor receptor gene (EGFR) demonstrate sensitivity to gefitinib or erlotinib. Investigators have reported an association between EGFR mutations and the amount and duration of cigarette smoking, with the highest incidence of mutations seen in never smokers. Methods EGFR exon 19 and 21 mutation status was determined in 265 tumor samples using direct sequencing, polymerase chain reaction (PCR), or PCR-based restriction fragment length polymorphism analysis. A detailed smoking history was obtained. Patients were categorized as never smokers (< 100 lifetime cigarettes), former smokers (quit ≥ 1 year ago), or current smokers (quit < 1 year ago). Results We detected EGFR mutations in 34 (51%) of 67 never smokers (95% CI, 38% to 64%), 29 (19%) of 151 former smokers (95% CI, 13% to 27%), and two (4%) of 47 current smokers (95% CI, 1% to 16%). Significantly fewer EGFR mutations were found in people who smoked for more than 15 pack-years (P < .001) or stopped smoking less than 25 years ago (P < .02) compared with individuals who never smoked. The number of smoking pack-years and smoke-free years predicted the prevalence of EGFR mutations (areas under receiver operating characteristic curve = 0.78 and 0.77, respectively). Conclusion The likelihood of EGFR mutations in exons 19 and 21 decreases as the number of pack-years increases. Mutations were less common in people who smoked for more than 15 pack-years or who stopped smoking cigarettes less than 25 years ago. These data can assist clinicians in assessing the likelihood of exon 19 and 21 EGFR mutations in patients with lung adenocarcinoma when mutational analysis is not feasible.


Author(s):  
Christoforos Astaras ◽  
Adrienne Bettini ◽  
Daniel C. Betticher

In advanced non-small cell lung cancer (NSCLC), epidermal growth factor receptor (EGFR) mutations are one of the most frequent oncogenic drivers. They confer a favorable prognosis and strongly predict sensitivity to EGFR tyrosine kinase inhibitors (TKIs). Over the last decades, several EGFR genetic alterations, common and uncommon mutations, have been described in exons 18−21. Common mutations are exon 19 deletions (most frequently E746-A750) and exon 21 L858R substitution. Uncommon mutations include exon 18 G719X, exon 20 S768l, exon 21 L861Q and many other rare ones. This report describes the case of a 55-year-old woman with a newly diagnosed metastatic lung adenocarcinoma harboring two rare EGFR mutations and showing sustained response to osimertinib.


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