scholarly journals EGFR Mutation Analysis of Circulating Tumor DNA Using an Improved PNA-LNA PCR Clamp Method

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Kana Watanabe ◽  
Tatsuro Fukuhara ◽  
Yoko Tsukita ◽  
Mami Morita ◽  
Aya Suzuki ◽  
...  

Introduction. Rebiopsies have become more crucial in non-small cell lung cancer (NSCLC). Instead of invasive biopsies, development of collecting biological data of the tumor from blood samples is expected. We conducted a prospective study to assess the feasibility of detection of epidermal growth factor receptor (EGFR) mutation in plasma samples.Method. NSCLC patients harboring EGFR activating mutations, who were going to receive EGFR-tyrosine kinase inhibitors (TKIs) as first-line treatment, were enrolled in this study. Plasma EGFR activating mutations and the T790M resistance mutation were analyzed by an improved PNA-LNA PCR clamp method, characterized by a 10-fold or more sensitivity compared with the original methods.Result. Six patients with wild-type EGFR and 24 patients with EGFR mutations were enrolled in this study. Pretreatment plasma samples achieved sensitivity of 79%. The 6 patients with wild-type EGFR were all negative for plasma EGFR mutations. At the time of disease progression, plasma T790M mutation was detected in 8 of 16 cases. Absence of T790M before and during TKI treatment and disappearance of activating mutations during TKI treatment were considered as predictors of EGFR-TKIs efficacy.Conclusion. We were able to detect EGFR mutations in plasma samples by using an improved PNA-LNA PCR clamp method.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e18039-e18039
Author(s):  
Giuseppe Altavilla ◽  
Mariacarmela Santarpia ◽  
Carmela Arrigo ◽  
Chiara Tomasello ◽  
Sara Benecchi ◽  
...  

e18039 Background: Approximately 70% of the pts. whose lung cancers harbor EGFR mutations acquire drug resistence after a response to EGFR tyrosine kinase inhibitors (TKIs) treatment; this acquired resistance is mainly due to a secondary mutation in EGFR (T790 M) in about 50% of patients, amplification of MET in 15%, PIK3CA mutations in 5%, an unknown mechanism in almost 30%, and SCLC transformation in some patients. Furthermore, clinical experience revealed that cancers with acquired resistance can respond again to TKIs, after a drug-free interval. To aid in identification and treatment of these patients we examined a cohort of patients whose cancers were assessed with tumor biopsies at multiple times before and after their treatment with TKIs. Methods: 21 lung adenocarcinomas pts. (10 male, 11 female, median age 53 years) with EGFR mutations at 19 or 21 exons received TKIs, as first line of treatment. All showed a clinical response and all relapsed ( mTTP 10 months). At the time of relapse a new biopsy was performed, histologic samples were reviewed to re-confirm the diagnosis, EGFR and MET amplification were identified by FISH, while EGFR mutations have been tested by DNA sequencing. Results: At the time that drug resistence was acquired all pts. retained their original activating EGFR mutations, 9 pts. developed EGFR T790M resistance mutation with pronunced EGFR amplification in 3, 2 pts. developed MET amplification, 8 biopsies did not reveal any new mutations, two pts. were found to have a diagnosis of small cell lung cancer in their drug resistant tumor biopsies and responded well to conventional chemotherapy regimen.15 of 19 confirmed lung adenocarcinoma patient underwent to a cisplatin - pemetrexed chemotherapy regimen and at the time of progression 10 of them accepted to undergo a new biopsy. Three pts. ( after 4, 5 and 6 months break from treatment with TKIs ) lost T790M mutation and their disease responded to a second-line course of erlotinib. Conclusions: In our cohort of pts. with acquired EGFR resistence some patients lost acquired T790M mutation and become sensitive to EGFR inhibitor, in addition, two pts. underwent the histologic transformation from NSCLC to SCLC at the time of TKI resistence.


2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e21627-e21627
Author(s):  
Corinna Woestmann ◽  
Christine Ju ◽  
Bernd Hinzmann ◽  
Stephanie J. Yaung ◽  
Michael Thomas ◽  
...  

e21627 Background: 15–40% of NSCLC adenocarcinoma patients harbor EGFR sensitizing mutations. Tyrosine kinase inhibitors (TKI) provide significant clinical benefit in this population, yet all patients will develop resistance. Liquid biopsy has been demonstrated to reliably identify tumor associated somatic EGFR mutations. Quantitative assessment of mutated EGFR driven tumors could potentially be used to monitor disease progression, to assess therapeutic response, and to identify resistance mechanisms. Methods: 106 longitudinal plasma samples from 16 NSCLC patients who were treated with osimertinib as either first line or second line therapy were collected. A series of plasma samples collected during treatment and at the time of disease progression were analyzed with the AVENIO ctDNA Surveillance kit*. Mutations at each time point were identified and reported by the AVENIO software v2.0*. The mutation profile of each patient at different timepoints along with the treatment journey was examined in combination with clinical outcome data. Results: EGFR sensitizing mutations were detected in all plasma samples by sequencing except in 3 cases. Patients responsive to anti-EGFR therapy showed a rapid decrease of EGFR driver mutations to non-detectable levels. Meanwhile, patients who had stable disease or rapid disease progression had stable or slightly decreasing ctDNA levels after receiving the treatment. One patient had a MET amplification, FBXL7 SNV, and EGFR T790M detected at the time of disease progression which were not detected at baseline. One patient had both EGFR L858R and T790M mutations. This patient progressed very quickly on erlotinib. Detection of the T790M mutation decreased upon osimertinib administration, however, the L858R mutation level stayed the same. TP53 mutations were elevated in 3 patients at the time of progression, and could potentially be related to anti-EGFR resistance. Conclusions: This study clearly demonstrated that liquid biopsy could identify resistance mutations beyond EGFR prior to clinical progression. Plasma samples collected prior to or at disease progression could facilitate identification of novel resistant mutations to TKI therapy. Further studies to demonstrate the clinical utility of serial blood EGFR testing in NSCLC management are necessary. *For Research Use Only. Not for use in diagnostic procedures.


Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3192
Author(s):  
Yukari Tsubata ◽  
Ryosuke Tanino ◽  
Takeshi Isobe

The discovery of activating mutations in the epidermal growth factor receptor (EGFR) gene and the development of EGFR tyrosine kinase inhibitors (TKIs) have led to a paradigm shift in the treatment of non-small cell lung cancer (NSCLC). EGFR mutation-positive NSCLC is common in East Asia, and approximately 50% of adenocarcinomas harbor EGFR mutations. Undoubtedly, EGFR-TKIs, with their promising efficacy, are the mainstay of primary therapy. However, even if tumor shrinkage is achieved, most patients become resistant to EGFR-TKIs and relapse; hence, EGFR-TKIs do not achieve a radical cure. The problem of the development of resistance to targeted drugs has been a persistent challenge. After the role of EGFR T790M mutation in acquired drug resistance was reported, osimertinib, a third-generation irreversible EGFR-TKI, was designed to overcome the resistance conferred by T790M mutation. In addition, some studies have reported the mechanism of drug resistance caused by mutations other than the T790M mutation and strategies to overcome them. Elucidating the mechanism underlying drug resistance development and combining therapeutic approaches are expected to further improve NSCLC prognosis.


2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e18114-e18114
Author(s):  
Andres Felipe Cardona Zorrilla ◽  
Oscar Arrieta ◽  
Guillermo Federico Bramuglia ◽  
Alma Delia Campos-Parra ◽  
Henry Alberto Becerra Ramirez ◽  
...  

e18114 Background: Previous exploratory analysis of EGFR status in tumor samples from five LATAM countries suggested that frequency of mutations lies between that of Asian and Caucasian populations and therefore support the genetic heterogeneity of NSCLC around the world. Methods: We analyzed the EGFR sequence of tumor samples from advanced stage NSCLC patients previously participated in the CLICaP registry. We compared the outcomes (overall and progression free survival) of 175 patients (from Argentina, Colombia and México) with an activating EGFR mutation with 414 subjects without this condition. Results: Mutations were more frequent in women (57,1%), in patients who had never smoked (67,4%), and in those with adenocarcinomas (89,4%) (P<0,002 for all comparisons). The mutations were deletions in exon 19 (58,3%) and L858R (36%). Median progression-free survival and overall survival for 175 patients who received tyrosine-kinase inhibitors (TKIs) were 13-mo (95%CI 11,2-14,8) months and 36-mo (95%CI 25,4-46,5), respectively. TKIs produced higher response rates (used as first or second line therapy) in the EGFR mutation-positive patients (70,8% vs. 29,2%; P<0,001), as well as improved PFS (13,0 vs. 3,0; P<0,001). OS is significantly different between treatment groups (36 vs. 14; P<0,001). Conclusions: The analysis of a large comparative registry of Latin-American EGFR mutated and wild type patients confirms the results of individual clinical trials previously published.


2021 ◽  
Vol 11 ◽  
Author(s):  
Liang Shi ◽  
Junfang Tang ◽  
Hong Tao ◽  
Lili Guo ◽  
Weihua Wu ◽  
...  

BackgroundWe aimed to investigate the feasibility of detecting epidermal growth factor receptor (EGFR) mutations in cell-free DNA (cfDNA) from cerebrospinal fluid (CSF) and plasma of advanced lung adenocarcinoma (LADC) with brain metastases (BMs) by droplet digital polymerase chain reaction (ddPCR).MethodsThirty advanced LADC patients with BMs were enrolled, and their matched CSF and plasma samples were collected. Droplet digital PCR was used to test cfDNA in CSF and plasma for EGFR mutation status. The clinical response and prognosis were evaluated.ResultsOut of 30 patients, there were 21 females and 9 males, aged 34-75 years. In all of the cases, CSF cytology were negative. In ddPCR assays, 10 patients (33.3%) had EGFR mutation in CSF, including 3 cases of EGFR T790M mutation, and 16 patients (53.3%) had EGFR mutation in plasma, including 6 cases of EGFR T790M mutation. Five patients with activating EGFR mutations in CSF achieved an intracranial partial response (iPR) after combination treatment with the first-generation EGFR-tyrosine kinase inhibitors. Three patients with EGFR T790M mutations in CSF achieved iPR after second-line osimertinib treatment. The median overall survival and intracranial progression-free survival were 17.0 months and 11.0 months, respectively.ConclusionIt was feasible to test EGFR mutation in cerebrospinal fluid and plasma. In LADC patients with brain metastasis, cerebrospinal fluid can be used as a liquid biopsy specimen to guide treatment strategy by monitoring EGFR mutation status.


2013 ◽  
Vol 31 (15_suppl) ◽  
pp. e19106-e19106
Author(s):  
Eduardo Castanon ◽  
Maria D. Lozano ◽  
Juan Pablo Fusco ◽  
Estefania Arevalo ◽  
Omar Esteban Carranza ◽  
...  

e19106 Background: LM appear in 20-30% of pts diagnosed with NSCLC and they confer PP. However, whether the clinical outcome of NSCLC pts with LM harboring molecular alterations in EGFR, KRAS and EML4-ALK genes is substantially different depending on their distinct status is still unknown. Methods: A total of 268 consecutive stage IV NSCLC pts were included. The tumor molecular analysis for EGFR, KRAS and EML4-ALK was available in 205 pts (76.5%), 136 pts (50.7%) and 31 pts (11.6%), respectively. An EGFR mutation was observed in 32 pts (15.6%), KRAS was mutated in 28 pts (20.6%) and EML4-ALK gene rearrangement was observed in 3 pts (9.6%). We aimed to determine whether the molecular status of EGFR, KRAS and EML4-ALK has an impact on the clinical outcome of stage IV NSCLC pts. Results: Most of the pts were men (71.3%). The most common histology was adenocarcinoma (59.3%). Overall, 34% of the pts showed LM at any time of the disease course. Among the whole cohort, median OS for LM pts was 16 months vs 42 months for pts with metastases other than LM (p<0.001). Among pts with LM and EGFR mutations, the one-year survival rate was 85.7% vs 54.3% for pts with LM and EGFR wild-type (p=0.03). We analyzed whether pts received EGFR TKI or standard chemotherapy (SC). For the subgroup of pts carrying EGFR mutations and receiving TKI, the 18-month survival rate was 75% for those showing LM vs 80% (p=0.44) for those without LM. In contrast, for the subgroup of EGFR wild-type pts receiving SC, the 18-month survival rate was 32.4% for those showing LM vs 74.9% for those without LM (p<0.001). No impact of KRAS or EML4-ALK molecular alterations on OS of pts with LM was observed. Conclusions: The presence of LM at any time of the disease curse negatively impacts on the clinical outcome of NSCLC pts. However, the presence of EGFR activating mutations significantly improves the OS of those with liver spread, reaching a similar OS to subjects with no LM. Pts with EGFR mutations and LM may revert the PP associated to LM when an EGFR TKI is prescribed.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e23033-e23033
Author(s):  
Veena M. Singh ◽  
Anthony J. Daher ◽  
Jeffery J. Chen ◽  
Lyle Arnold ◽  
Cecile Rose T. Vibat

e23033 Background: Targeted cancer therapy relies on identifying specific DNA mutations from a patient’s tumor. Tyrosine kinase inhibitors (TKIs) tend to be effective for non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) activating mutations, of which exon 19 deletions (Del19) and L858R are most common. Acquired resistance to TKI therapy is associated with a T790M mutation. Standard biomarker analyses may not reflect tumor heterogeneity; they entail tissue biopsies often with surgical complications. To address these limitations, Biocept developed a minimally invasive method to characterize cancer biomarkers in blood. Biocept's proprietary TargetSelector assays selectively amplify relevant mutations from circulating tumor DNA (ctDNA). Clinical validations demonstrated high concordances between molecular tests in blood vs tissue. As further validation, EGFR mutation detection frequencies were compared to US averages (mycancergenome.org). Here we analyze 2000 blood samples received at Biocept from 1Mar 2016 to 4Jan 2017 from late stage NSCLC patients. Methods: Blood was collected in Biocept OncoCEE BCT validated to preserve DNA ≤ 8 days. TargetSelector was used to detect ctDNA L858R, Del19 and T790M.EGFR allele copy numbers for wild type and each mutant were calculated. The prevalence of each mutation was compared to US averages. Results: Del19, L858R, and T790M mutations were detected in 12.9%, 8.5%, and 9.9% of the analyzed blood samples, respectively. This is concordant with US averages, which are 10% for each mutation. Median copy numbers/ml of blood were 30 for Del19 (range: 1 – 91974), 15 for L858R (range: 1 – 91200), and 10 for T790M (range: 1 – 137360). The median wild type EGFR copy number detected/ml blood was 2304 (range: 8 – 2498725). In ~80% of T790M cases, ≥ 1 concomitant activating mutation was detected. Conclusions: Biocept's TargetSelector detects EGFR mutations (Del19, L585R, and T790M) at a very high level of sensitivity down to 1 mutant copy/ml in advanced NSCLC patients at frequencies consistent with cited US rates. Moreover, the underlying activating mutation was detected in ~80% of T790M cases.


2021 ◽  
Vol 15 ◽  
pp. 117955492199307
Author(s):  
Klaus Hackner ◽  
Anna Buder ◽  
Maximilian J Hochmair ◽  
Matthaeus Strieder ◽  
Christina Grech ◽  
...  

Background: Proof of the T790M resistance mutation is mandatory if patients with EGFR-mutated non-small cell lung cancer (NSCLC) progress under first- or second-generation tyrosine kinase inhibitor therapy. In addition to rebiopsy, analysis of plasma circulating tumor DNA is used to detect T790M resistance mutation. We studied whether sputum is another feasible specimen for detection of EGFR mutations. Methods: Twenty-eight patients with advanced EGFR-mutated NSCLC were included during stable and/or progressive disease. The initial activating EGFR mutations (exon 19 deletions or L858R mutations) at stable disease and at progressive disease (together with T790M) were assessed in simultaneously collected plasma and sputum samples and detected by droplet digital polymerase chain reaction (ddPCR). Results: Activating EGFR mutations were detected in 47% of the plasma samples and 41% of sputum samples during stable disease, and in 57% of plasma samples and 64% of sputum samples during progressive disease. T790M was detected in 44% of the plasma samples and 66% of the sputum samples at progressive disease. In ddPCR T790M-negative results for both specimens (plasma and sputum), negativity was confirmed by rebiopsy in 5 samples. Concordance rate of plasma and sputum for T790M was 0.86, with a positive percent agreement of 1.0 and a negative percent agreement of 0.80. Conclusions: We demonstrated that EGFR mutation analysis with ddPCR is feasible in sputum samples. Combination of plasma and sputum analyses for detection of T790M in NSCLC patients with progressive disease increases the diagnostic yield compared with molecular plasma analysis alone.


2020 ◽  
Vol 16 (21) ◽  
pp. 1537-1547
Author(s):  
Fumio Imamura ◽  
Madoka Kimura ◽  
Yukihiro Yano ◽  
Masahide Mori ◽  
Hidekazu Suzuki ◽  
...  

Aim: Osimertinib is a key drug for EGFR mutation-positive non-small-cell lung cancer (NSCLC). As the hazards ratio of overall survival in comparison with first-generation EGFR-tyrosine kinase inhibitors was almost similar between FLAURA and ARCHER 1050, salvage use of osimertinib is still a treatment option. Patients & methods: We retrospectively analyzed the clinical courses of EGFR mutation-positive NSCLC patients who were potential candidates for salvage osimertinib. Results: Among 524 patients enrolled from five hospitals, 302 patients underwent biopsy, with 52.6% detection rate of T790M. Osimertinib was administered in 93.6% of the T790M-positive patients. The overall response rate and median progression-free survival time of osimertinib were calculated with 147 patients, to be 55.6% and 17.2 months, respectively. Conclusion: Osimertinib is active for T790M-driven acquired resistance in EGFR-mutant NSCLC, but the detection of T790M was unsatisfactory. Clinical Trial Registration: UMIN000028989 (UMIN Clinical Trials Registry)


2021 ◽  
pp. 107815522110191
Author(s):  
Pinar Gursoy

Introduction Most patients with non-small-cell lung cancer tumors that have epidermal growth factor receptor (EGFR) mutations have deletion mutations in exon 19 or exon 21, or both.In recent years, targeted therapies in lung cancer have increased survival, but the development of resistance to these drugs poses a major problem. Thesubstitution of methionineforthreonine at position 790 (T790M) mutation,is primarily responsible for this resistance. However, after osimertinib used in T790M positivepatients treatment options are generally limited to chemotherapy. Case report We reported the efficacy of erlotinib, which we reapplied due to the disappearance of the resistance mutation after osimertinib in a 68-year-old patient using osimertinib after erlotinib. Management and outcome: In the patient using erlotinib due to exon 19 deletion when progression was observed and T790M positivity was detected, osimertinib treatment was initiated. However, when T790M was found to be negative with rebiopsy in progression after osimertinib, a complete response was achieved by restarting erlotinib. Discussion The strategy of restarting erlotinib treatment with negative T790M mutation detected in biopsies of patients with osimertinib resistance may be an acceptable treatment option.


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