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Background: About 50–60% treatment-naïve advanced non-small-cell lung cancers were coexistence of epidermal growth factor receptor (EGFR) and mesenchymal epithelial transition (MET) overexpression. However, few studies demonstrated the prognostic value of MET protein expression in untreated EGFR-mutant lung adenocarcinoma (LUAD). Methods: A total of 235 EGFR-mutant untreated advanced LUAD patients were retrospectively enrolled. MET expression was determined using immunohistochemistry, and MET positivity was defined as 2 + or 3 + using the METmab scoring algorithm. Progression-free survival (PFS) and overall survival (OS) were analysed according to MET expression status. Independent factors predicting prognosis were identified using multivariate Cox regression analyses. Results: Of the 235 patients, 113 (48.1%) harboured exon 19 deletion (19_del), 103 (43.8%) had exon 21 L858R mutations, and 19 (8.1%) had other mutation types, including exon 21 L861Q, exon 18 G719A/C, exon 20 S768I, and L858R/19_del double mutations. MET-positive expression was observed in 192 (81.7%) cases. There was no significant difference in baseline clinicopathological characteristics between MET positivity and MET negativity groups. Patients were stratified by different EGFR mutation subtypes. MET-positive patients in the L858R mutation subgroup had markedly shorter PFS and OS than MET-negative patients (median PFS: 13 versus 27.5 months, p < 0.001; median OS: 29 versus not reached, p = 0.008), but no significant difference was observed in the 19_del subgroup. Multivariate Cox regression analyses indicated that MET positivity was an independent predictor for poor PFS and OS in L858R subgroup (PFS: HR = 3.059, 95% CI 1.552–6.029, p = 0.001; OS: HR = 3.511, 95% CI 1.346–9.160, p = 0.010). Additionally, an inferior survival outcome of MET positivity was observed in the L858R mutation subgroup when treated with EGFR–tyrosine kinase inhibitor (TKI) monotherapy as the first-line regimen (median PFS: 13 versus 36.5 months, p < 0.001; median OS: 29 versus not reached, p = 0.012) but not with EGFR–TKI plus platinum doublet chemotherapy. Conclusions: MET positive expression was an independent predictor of poor outcomes in untreated EGFR L858R mutation advanced LUAD patients treated with first-line EGFR–TKI monotherapy. [ABSTRACT FROM AUTHOR]

Different efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) has been observed between lung cancer patients with 19 exon deletion (19Del) and with L858R mutation. We investigate the multi-omics information from the TCGA Lung adenocarcinoma (LUAD) dataset and validate it using the GEO (GSE190139, GSE147377) and MSK datasets. Somatic loss-of-function alteration of RBM10 and altered Immune infiltration profile correlated with L858R decreased survival. Meanwhile, 9p21.3 loss, CDKN2B methylation, and increased cell cycle-related gene expression are differential characteristics in the L858R mutation group. Comprehensive genomic and phenotypic analysis of the EGFR-mutated lung cancer subtypes reveals distinctive features of each subtype, laying the groundwork for subtype-specific treatment and care options for lung cancer patients. [ABSTRACT FROM AUTHOR]

Abstract Background In the current treatment landscape for non-small cell lung cancers, epidermal growth factor receptor-tyrosine kinase inhibitors have emerged as a well-established treatment option for patients with advanced or metastatic disease. This is particularly true for those with commonly occurring epidermal growth factor receptor mutations. However, the therapeutic efficacy of these agents for so-called rare epidermal growth factor receptor mutations, and in particular those characterized by a high degree of complexity, such as double mutations, remains a subject of clinical uncertainty. Case presentation In this context, we present the case of a 64-year-old man of Moroccan descent, a lifelong non-smoker, diagnosed with metastatic non-small cell lung cancer characterized by a complex epidermal growth factor receptor mutation encompassing L858R and S768I. The patient subsequently underwent afatinib-based treatment, showing notable clinical results. These included a remarkable overall survival of 51 months, with a median progression-free survival of more than 39 months. Conclusions This case report is a compelling testimony to the evolving therapeutic landscape of non-small cell lung cancers, providing valuable insight into the potential therapeutic efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors in the realm of rare and complex epidermal growth factor receptor mutations.

Pulmonary enteric adenocarcinoma (PEAC) is a rare lung adenocarcinoma with morphological and immunohistochemical similarities to colorectal adenocarcinoma and intestinal differentiation. PEAC belongs to the group of non-small-cell lung carcinoma (NSCLC) and is defined as having a more than 50% intestinal differentiation component. We report a postoperative (T4N2M0 stage IIIb) PEAC patient with EGFR L858R + A871G combined mutation. Following surgery, the patient underwent treatment with the first-generation EGFR-TKI, gefitinib, and achieved an impressive 5-year progression-free survival (PFS). This suggests that gefitinib may serve as an effective treatment option for PEAC patients with EGFR L858R + A871G compound mutations. [ABSTRACT FROM AUTHOR]

Aumolertinib, as a novel third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been widely employed as a first-line treatment for advanced non-small cell lung cancer (NSCLC) patients with EGFR mutation. However, reports regarding the benefit of using aumolertinib as a monotherapy in pulmonary giant cell carcinoma are relatively scarce. In this report, we present a pulmonary giant cell carcinoma case harboring the EGFR Leu858Arg (L858R) mutation, with the patient at stage cT2bN3M1c IVB. Through the use of autolearning as a single agent, we effectively controlled the progression of pulmonary giant cell carcinoma, achieving a 6-month progression-free survival during the treatment course. Notably, the patient’s tumor not only ceased its growth but also continued to shrink, highlighting a significant therapeutic effect. This case reveals the effectiveness of aumolertinib as a monotherapy in controlling disease progression. The finding underscores the therapeutic advantage of aumolertinib in this particular subgroup of patients, offering a novel treatment option for pulmonary giant cell carcinoma.

Background: EGFR tyrosine kinase (TKIs) are recommend as the first-line treatment for non-small cell lung cancer (NSCLC) patients with EGFR mutation. However, some patients experience aggressive progression with a progression-free survival (PFS) less than 6 months on the first-line EGFR TKI therapy. Therefore, our study is to analyze the potential influencing factors including clinical features, biomarkers, concomitant mutations et al. Methods: A total of 1073 NSCLC patients with EGFR mutation in a multi-center study from January 2019 to December 2021. The datum pathological and molecular characteristics were collected. The area under the receiver operating characteristic (ROC) curve was used to evaluate the predictive effect of Ki-67 on the first-line TKI. The curve of PFS was conducted by Kaplan–Meier method and tested by bilateral log-rank. Cox regression model was used to predict and evaluate PFS of different variables. Chi-square or Fisher analysis was used for correlation between groups. Results: 55 patients who show aggressive progression (PFS ≤ 6 months) on the first-line TKI therapy were analyzed in this study, while 71 with slow progression (PFS > 6 months). Concomitant mutations including AXIN2, P2CG and RAD51C mutations occurred only in the aggressively progressive group (P = 0.029). Correlation between Ki-67 index and the aggressive progression of the first-line TKI therapy was significant statistically different (P < 0.05). In the second-line therapy, the PFS of chemotherapy in combination with other treatments was better than single TKIs in the first ten months. Conclusion: NSCLC harbored EGFR and concomitant mutations (such as AXIN2, PLCG2 and RAD51C), and/or Ki-67 high expression may indicate the aggressive progression to the first-line EGFR-TKI. [ABSTRACT FROM AUTHOR]

Abstract Lung cancer with complex epidermal growth factor receptor (EGFR) and CTNNB1 comutations is rare, and the efficacy of tyrosine kinase inhibitors (TKIs) is generally poor. Here, we encountered a lung cancer patient with complex EGFR (L858R and E709X) and CTNNB1 comutations who successfully responded to afatinib. A 78‐year‐old woman visited our hospital with a cough and bloody sputum that had worsened over the past year. She had multiple mass shadows in both lungs and nodular shadows in the bronchi. The patient was diagnosed with lung adenocarcinoma cT4N3M1c stage IVB. A genetic analysis of the primary tumor using the Oncomine Dx target test multi‐CDx system revealed positivity for EGFR (L858R and E709X) and CTNNB1 mutations. The expression of programmed death ligand 1 (22C3 clones) in tumor cells was negative by immunostaining. The patient was treated with afatinib as first‐line therapy and achieved clinical improvement and a partial response and is continuing treatment 1 year later. Case reports of lung cancer patients with EGFR/CTNNB1 comutations are rare, and TKIs are not considered to be effective. We herein present the first case report of lung cancer with the co‐occurrence of uncommon and complex EGFR (L858R and E709X) and CTNNB1 mutations that was successfully treated with afatinib.

We previously reported that the combined application of Ephedra Herb extract (EHE) and epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), erlotinib, is effective in suppressing the growth of erlotinib-resistant non-small-cell lung cancer (NSCLC) cell line, H1993, xenograft tumor, and cell proliferation, and that EHE downregulates c-Met and wild-type EGFR in H1993 cells. However, it was unclear whether EHE could affect EGFR with active mutations. Clinically, advanced NSCLC patients who are eligible for EGFR-TKI treatment are those with detected EGFR with activating mutations. Therefore, it is important to clarify the effect of EHE on EGFR with activating mutations. H1975 cells express EGFR with activating mutations, L858R and T790M, and c-Met; this NSCLC cell line was used in the present study. EHE downregulated the expression of EGFR with activating mutations and c-Met, and inhibited autophosphorylation of c-Met. Proliferation of H1975 cells was suppressed by EHE in a concentration-dependent manner. These results suggest that EHE may be effective against NSCLC harboring EGFR with activating mutations. Considering the fact that advanced NSCLC patients, with an EGFR T790M mutation, are currently widely treated with the third-generation EGFR-TKI, osimertinib, we examined the combined effects of osimertinib and EHE on H1975 cells. The osimertinib and EHE combination downregulated the expression of these receptors and suppressed the proliferation of H1975 cells more effectively than did osimertinib alone, suggesting that this combination may be effective in treating patients with advanced NSCLC with the L858R + T790M EGFR mutation and c-Met. Graphical Abstract was created with BioRender.com. [ABSTRACT FROM AUTHOR]

A 68-year-old female presented to the emergency department with shortness of breath and right sided pleuritic chest pain. Chest computed tomography (CT) revealed pleural effusion occupying the right hemithorax. Thoracentesis showed a black-coloured pleural effusion. Fine needle biopsy of the pleura and bronchoscopic biopsy revealed lung adenocarcinoma with epidermal growth factor receptor (EGFR) L858R mutation. This case report describes a patient with an extremely rare case of pleural effusion. [ABSTRACT FROM AUTHOR]

Non-small cell lung cancer (NSCLC) is a major cause of cancer-related deaths around the world. Targeting the sensitized epidermal growth factor receptor (EGFR) caused by gene mutation through the tyrosine kinase inhibitor is an effective therapeutic strategy for NSCLC. Hence, the individualized therapeutic strategy has highlighted the demand for a simple, fast, and intelligent strategy for the genetic decoding of EGFR to cater to the popularization of precision medicine. In this research, a one-pot assay for EGFR identification is established by combining a loop-mediated isothermal amplification and amplification refractory mutation system. By optimizing the component and condition of the nucleic acid amplification system, a sensitive and specific distinguishability is achieved for tracing target variant (60 copies, 0.1%) identification under a strong interferential background within 40 min. Moreover, complex operation and time-consuming data processing, as well as the aerosol contamination, are avoided owing to the whole process for intelligent genetic decoding being performed in a sealed tube. As a demonstration, L858R, the primary point mutation for the sensitization of EGFR, has been accurately decoded using this assay with highly heterogeneous cancerous tissue. In addition, this method can be easily extended for other genetic information decoding using a tailor-made primer set. Thus, we propose that this straightforward strategy may serve as a promising tool for NSCLC diagnosis in clinical practice. [ABSTRACT FROM AUTHOR]

Introduction: The differences in biological characteristics among different genotypes of classical EGFR mutations have not been clarified. This study aimed to clarify the clinical and biological differences between L858R and 19 deletion in NSCLC. Methods: We analyzed a cohort of 191 consecutive cases of surgically resected NSCLC harboring EGFR driver mutations (L858R or 19 deletion) in which curative resection was performed in Aichi Cancer Center Hospital, Nagoya, Japan, from January 2006 to September 2021 and in which recurrence subsequently developed. We also subjected 61 surgically resected NSCLC specimens harboring EGFR driver mutations (L858R or 19 deletion) to an RNA sequencing analysis. Results: In patients with stage I disease, the median time to recurrence did not differ to a statistically significant extent between the types of EGFR mutations; however, among those with stage II and III disease, the median time to recurrence in patients with the L858R genotype tended to be shorter in comparison to those with 19 deletion (log-rank test, p = 0.47 and 0.46, respectively). In comparison to 19 deletion tumors, L858R tumors had higher cytological malignancy (e.g., mitotic ability) and showed stronger immunogenicity. Conclusion: L858R and 19 deletion tumors are likely to have a slight difference in the time to recurrence. They suggest that even in EGFR driver tumors, which are treated as the same disease category, the biological characteristics of the tumors are different, which may leave room for innovations in postoperative treatment and treatment at recurrence. [ABSTRACT FROM AUTHOR]

The clinicopathological presentation of early-stage lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutations has been seldom studied. Our study enrolled patients with stage I and II lung adenocarcinoma between January 2014 and December 2017 at the National Taiwan University Hospital. Clinicopathological features and prognosis were retrospectively reviewed and analyzed depending on EGFR mutation status. EGFR mutations were detected in 622 (60%) out of 1034 patients. Compared to the group without EGFR mutations, the group with EGFR mutations had more patients above 65 years of age (p < 0.001), more non-lepidic histological subtypes (p < 0.001), higher CEA levels (p = 0.044), higher grade of pleural (p = 0.02) and lymphovascular (p = 0.001) invasion, higher histological grade (p < 0.001), and a more advanced pathological stage (p = 0.022). In multivariate analysis, there was no significant difference in PFS or OS between the EGFR mutant and wild-type groups. In subtype analysis, the tumors with an L858R mutation had a more lepidic predominant histological type (p = 0.019) and less lymphovascular invasion (p = 0.011). No significant differences in PFS or OS were detected between the exon 19 deletion and L858R mutation groups. In early-stage lung adenocarcinoma, EGFR mutation may be considered as a treatment response predictor for tyrosine kinase inhibitors, instead of a predictor of clinical prognosis. [ABSTRACT FROM AUTHOR]

Lung cancer with complex epidermal growth factor receptor (EGFR) and CTNNB1 comutations is rare, and the efficacy of tyrosine kinase inhibitors (TKIs) is generally poor. Here, we encountered a lung cancer patient with complex EGFR (L858R and E709X) and CTNNB1 comutations who successfully responded to afatinib. A 78‐year‐old woman visited our hospital with a cough and bloody sputum that had worsened over the past year. She had multiple mass shadows in both lungs and nodular shadows in the bronchi. The patient was diagnosed with lung adenocarcinoma cT4N3M1c stage IVB. A genetic analysis of the primary tumor using the Oncomine Dx target test multi‐CDx system revealed positivity for EGFR (L858R and E709X) and CTNNB1 mutations. The expression of programmed death ligand 1 (22C3 clones) in tumor cells was negative by immunostaining. The patient was treated with afatinib as first‐line therapy and achieved clinical improvement and a partial response and is continuing treatment 1 year later. Case reports of lung cancer patients with EGFR/CTNNB1 comutations are rare, and TKIs are not considered to be effective. We herein present the first case report of lung cancer with the co‐occurrence of uncommon and complex EGFR (L858R and E709X) and CTNNB1 mutations that was successfully treated with afatinib. [ABSTRACT FROM AUTHOR]

Background: Zorifertinib (AZD3759), an epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) with high blood-brain barrier penetration capability, demonstrated promising intracranial and systemic antitumor activity in phase 1 and 2 studies in central nervous system (CNS)-metastatic patients., Methods: In this phase 3 EVEREST trial (ClinicalTrials.gov: NCT03653546), patients with EGFR-sensitizing mutations, advanced treatment-naive non-small cell lung cancer (NSCLC), and non-irradiated symptomatic or asymptomatic CNS metastases were randomized (1:1) to zorifertinib or first-generation EGFR-TKI (gefitinib or erlotinib; control). The primary endpoint was blinded independent central review (BICR)-assessed progression-free survival (PFS) per RECIST1.1., Findings: Overall, 439 patients were randomized (zorifertinib n = 220; control n = 219). Most patients had the EGFR L858R mutation (55%) or >3 CNS lesions (54%). Median PFS was significantly longer with zorifertinib versus control (9.6 versus 6.9 months; hazard ratio [HR], 0.719; 95% confidence interval [CI], 0.580-0.893; p = 0.0024). Zorifertinib significantly prolonged intracranial PFS versus control (BICR per modified RECIST1.1: HR, 0.467; 95% CI, 0.352-0.619; investigator per RANO-BM: HR, 0.627; 95% CI, 0.466-0.844). Overall survival (OS) was immature; the estimated median OS was 37.3 months with zorifertinib and 31.8 months with control (HR, 0.833; 95% CI, 0.524-1.283) in patients subsequently treated with third-generation EGFR-TKIs. Safety profiles were consistent with previously reported data for zorifertinib., Conclusions: Zorifertinib significantly improved systemic and intracranial PFS versus first-generation EGFR-TKIs; adverse events were manageable. Sequential use of zorifertinib and third-generation EGFR-TKIs showed the potential to prolong patients' survival. The results favor zorifertinib as a novel, well-validated first-line option for CNS-metastatic patients with EGFR-mutant NSCLC., Funding: This work was funded by Alpha Biopharma (Jiangsu) Co., Ltd., China., Competing Interests: Declaration of interests Q.Z. declares lecture and presentation fees from AstraZeneca, Boehringer Ingelheim, BMS, Eli Lilly, MSD, Pfizer, Roche, and Sanofi. S.L. declares grants or contracts from AstraZeneca, Hutchison, BMS, Hengrui, BeiGene, Roche, and Hansoh; consulting fees from AstraZeneca, Pfizer, Boehringer Ingelheim, Hutchison Medipharma, Simcere, Zai Lab, GenomiCare, Yuhan, prlME Oncology, Menarini, InventisBio, and Roche; lecture and presentation fees from AstraZeneca, Roche, Hansoh, and Hengrui Therapeutics; participation on a data safety monitoring board or advisory board for Roche, Regeneron, AstraZeneca, and Xcovery Holdings; and a leadership or fiduciary role in the Chinese Lung Cancer Associate and CSCO. Z. Wang is an employee of Alpha Biopharma (Jiangsu) and declares no stock ownership in the company. M.-J.A. declares consulting fees from AstraZeneca, Amgen, Merck, Takeda, BMS, ONO, Roche, Daiichi-Sankyo, Janssen, Alpha Pharmaceuticals, Yuhan, Arcus Biosciences, Eutilex, and VORONOI and lecture and presentation fees from AstraZeneca, Amgen, Merck, Takeda, BMS, ONO, Roche, Daiichi-Sankyo, Janssen, and Yuhan. Y.-L.W. declares consulting services for AstraZeneca, Boehringer Ingelheim, Novartis, and Takeda; lecture and presentation fees from AstraZeneca, BeiGene, Boehringer Ingelheim, BMS, Eli Lilly, MSD, Pfizer, Roche, and Sanofi; and grants or contracts from AstraZeneca, Boehringer Ingelheim, BMS, Hengrui, and Roche., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Epidermal growth factor receptor (EGFR) mutation screening in non-small cell lung cancer (NSCLC) is now used to guide treatment decisions to identify patients with EGFR positive mutations that predict response to EGFR tyrosine kinase inhibitors. This study aimed to explore with a prospective study the current testing practices and the predictive value of EGFR mutations in a series of 261 patients with NSCLC. EGFR mutation testing was conducted using 2 different assays: bidirectional Sanger sequencing of polymerase chain reaction (PCR) and real-time PCR on the Rotor-Gene Q instrument. Epidermal growth factor receptor mutation testing was performed for 261 patients with lung cancer. Exons 18 to 21 were successfully analyzed in 113 tumors by Direct sequencing and in 148 tumors by real-time PCR. The prevalence of positive EGFR-mutations in each method was 22.1% (N = 25) and 24.3% (N = 36), respectively (P = .3). In total, EGFR mutations were detected in 59 patients among 261 patients with NSCLC. A statistically significant association between female sex, nonsmoking history, nonsolid major pattern, and a higher EGFR mutation frequency. In this study, we investigated clinicopathological differences between tumors harboring exon 19del and those harboring L858R. We did not find any significant differences between the 2 mutations and gender or smoking features, interestingly, the prevalence of patients aged >60 years was significantly higher in the L858R group than in the exon 19del group (81.8% vs 55.8%, P = .05). A significant association was observed between exon 19 deletions and the papillary major pattern, but no correlation was detected between exon 21 mutation and any histological pattern. This prospective study documented the real-world clinical testing of EGFR mutation in Moroccan NSCLC patients. Our experience confirms the need to develop standards-based guidelines for the routine performance and evaluation of EGFR testing to improve clinical care for this subset of lung cancer. On the other hand, our study demonstrated that tumors with exon 19 deletions and L858R harbor specific clinicopathological features in NSCLC. [ABSTRACT FROM AUTHOR]

Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) first-line therapy, has shown good clinical outcomes in non-small cell lung cancer (NSCLC), but some serious adverse events such as cardiotoxicity have also been reported. Here, we present the first NSCLC case with osimertinib-induced cardiac failure. The case is successfully being treated by switching to another third-generation TKI, aumolertinib. A 62-year-old non-smoking woman was initially diagnosed with stage cT2aN2M1c IVB NSCLC with synchronous brain and bone metastasis in April 2020. Further genetic screening of the patient identified Leu858Arg (L858R) mutation in EGFR; thus, the patient was administered third-generation TKI osimertinib (80 mg/day) for 6 months. This treatment with osimertinib led to serious cardiac failure but no significant reduction in NSCLC tumor size. To cope with these conditions, another third-generation TKI, aumolertinib (110 mg/day), along with a supplement treatment plan was prescribed to the patient. Interestingly, this new treatment plan of aumolertinib significantly inhibited tumor growth in 8 months. Therefore, we conclude that the administration of second-line aumolertinib 110 mg/day has fewer adverse reactions and high efficacy against NSCLC as compared to osimertinib therapy. [ABSTRACT FROM AUTHOR]

Pulmonary pleomorphic carcinoma (PPC) has an aggressive clinical course and poor prognosis mainly because of the difficulty in achieving therapeutic effects. Despite a small fraction of patients with PPC possessing an epidermal growth factor receptor (EGFR) activating mutation, only a limited number of studies have reported the efficacy of EGFR tyrosine kinase inhibitors in those patients. Here, we present successful treatment with first-line afatinib in a patient with EGFR mutation-positive, metastatic PPC.

Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) first-line therapy, has shown good clinical outcomes in non-small cell lung cancer (NSCLC), but some serious adverse events such as cardiotoxicity have also been reported. Here, we present the first NSCLC case with osimertinib-induced cardiac failure. The case is successfully being treated by switching to another third-generation TKI, aumolertinib. A 62-year-old non-smoking woman was initially diagnosed with stage cT2aN2M1c IVB NSCLC with synchronous brain and bone metastasis in April 2020. Further genetic screening of the patient identified Leu858Arg (L858R) mutation in EGFR; thus, the patient was administered third-generation TKI osimertinib (80 mg/day) for 6 months. This treatment with osimertinib led to serious cardiac failure but no significant reduction in NSCLC tumor size. To cope with these conditions, another third-generation TKI, aumolertinib (110 mg/day), along with a supplement treatment plan was prescribed to the patient. Interestingly, this new treatment plan of aumolertinib significantly inhibited tumor growth in 8 months. Therefore, we conclude that the administration of second-line aumolertinib 110 mg/day has fewer adverse reactions and high efficacy against NSCLC as compared to osimertinib therapy.

Hengrui Liang,1,* Caichen Li,1,* Yi Zhao,1,* Shen Zhao,2,* Jun Huang,1 Xiuyu Cai,2,3 Bo Cheng,1 Shan Xiong,1 Jianfu Li,1 Wei Wang,1 Changbin Zhu,4 Weiwei Li,5 Jianxing He,1 Wenhua Liang1 1Department of Thoracic Surgery and Oncology, The First Affiliated Hospital of Guangzhou Medical University, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, Guangzhou, People’s Republic of China; 2Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 3Department of General Internal Medicine, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 4BGI Genomics, BGI-Shenzhen, Shenzhen 518083, People’s Republic of China; 5BGI-Guangzhou Medical Laboratory, BGI-Shenzhen, Guangzhou 510006, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jianxing He; Wenhua LiangDepartment of Thoracic Surgery and Oncology, The First Affiliated Hospital of Guangzhou Medical University, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, Guangzhou 510120, People’s Republic of ChinaTel +86-20-83337792Fax +86-20-83350363Email liangwh1987@163.comObjective: Differences in efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) have been observed between non-small cell lung cancer (NSCLC) patients with 19 exon deletion (19Del) and L858R mutation. We explored whether the total number or pattern of concomitant mutations of 19Del and L858R may explain their different sensitivities.Patients and Methods: This study contained the mutational profiles of EGFR-mutated NSCLC patients from two cohorts: Guangzhou (G1) and database (G2). Concomitant mutation status and EGFR-TKI response information were retrieved.Results: A total of 403 patients covered 283 genes in the G1 and 803 patients with a different gene set in the G2 were included. Similar prevalence of total concomitant mutation number was observed in both G1 ( 19Del 32.48% vs L858R 30.45%; P=0.68) and G2 ( 19Del 74.9% vs L858R 73.2%; P=0.65) cohorts. Only HGF/c-Met pathway same more related to L858R mutation. EGFR-TKI response information was recorded for 134 patients in the G2 cohort. 19Del showed a higher objective response (OR) rate compared with L858R, regardless of concomitant mutations. Compared to patients with OR, non-OR patients had more concomitant mutations, both in 19Del (53.8% vs 83.3%; P=0.021) and L858R (51.4% vs 77.8%; P=0.029). In particular, total concomitant mutations (OR=0.27; P=0.03), sensitive EGFR mutations (OR=2.21; P=0.04), and T790M (OR=0.244; P=0.02) significantly affected the TKI response.Conclusion: Concomitant mutations were widespread in 19Del and L858R and were associated with poorer OR to EGFR-TKIs. However, 19Del and L858R had similar numbers and patterns of concomitant mutations, which might not explain the different sensitivity to EGFR-TKI.Keywords: epidermal growth factor receptor mutation, 19Del, L858R, non-small cell lung cancer, concomitant mutation

Non-small cell lung cancer (NSCLC) is a major cause of cancer-related deaths around the world. Targeting the sensitized epidermal growth factor receptor (EGFR) caused by gene mutation through the tyrosine kinase inhibitor is an effective therapeutic strategy for NSCLC. Hence, the individualized therapeutic strategy has highlighted the demand for a simple, fast, and intelligent strategy for the genetic decoding of EGFR to cater to the popularization of precision medicine. In this research, a one-pot assay for EGFR identification is established by combining a loop-mediated isothermal amplification and amplification refractory mutation system. By optimizing the component and condition of the nucleic acid amplification system, a sensitive and specific distinguishability is achieved for tracing target variant (60 copies, 0.1%) identification under a strong interferential background within 40 min. Moreover, complex operation and time-consuming data processing, as well as the aerosol contamination, are avoided owing to the whole process for intelligent genetic decoding being performed in a sealed tube. As a demonstration, L858R, the primary point mutation for the sensitization of EGFR, has been accurately decoded using this assay with highly heterogeneous cancerous tissue. In addition, this method can be easily extended for other genetic information decoding using a tailor-made primer set. Thus, we propose that this straightforward strategy may serve as a promising tool for NSCLC diagnosis in clinical practice.

The clinicopathological presentation of early-stage lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutations has been seldom studied. Our study enrolled patients with stage I and II lung adenocarcinoma between January 2014 and December 2017 at the National Taiwan University Hospital. Clinicopathological features and prognosis were retrospectively reviewed and analyzed depending on EGFR mutation status. EGFR mutations were detected in 622 (60%) out of 1034 patients. Compared to the group without EGFR mutations, the group with EGFR mutations had more patients above 65 years of age (p < 0.001), more non-lepidic histological subtypes (p < 0.001), higher CEA levels (p = 0.044), higher grade of pleural (p = 0.02) and lymphovascular (p = 0.001) invasion, higher histological grade (p < 0.001), and a more advanced pathological stage (p = 0.022). In multivariate analysis, there was no significant difference in PFS or OS between the EGFR mutant and wild-type groups. In subtype analysis, the tumors with an L858R mutation had a more lepidic predominant histological type (p = 0.019) and less lymphovascular invasion (p = 0.011). No significant differences in PFS or OS were detected between the exon 19 deletion and L858R mutation groups. In early-stage lung adenocarcinoma, EGFR mutation may be considered as a treatment response predictor for tyrosine kinase inhibitors, instead of a predictor of clinical prognosis.

Epidermal growth factor receptor (EGFR) is a transmembrane tyrosine kinase that is frequently modified by glycosylation post-translationally. In cancer, EGFR amplifications and hotspot mutations such as L858R that promote proliferation have been detected in a significant fraction of non-small cell lung carcinomas and breast adenocarcinomas. Molecular dynamic simulations suggested that glycosylation at asparagine residue 361 (N361) promotes dimerization and ligand binding. We stably expressed glycosylation-deficient mutant EGFR N361A, with or without the oncogenic mutation L858R. Immunofluorescence and flow cytometry demonstrated that the mutants were each well expressed at the cell membrane. N361A decreased proliferation relative to wild-type EGFR as well as decreased sensitivity to ligands. Proximity ligation assays measuring co-localization of EGFR with its binding partner HER2 in cells revealed that N361A mutations increased co-localization. N361A, located near the binding interface for the EGFR inhibitor necitumumab, desensitized cells expressing the oncogenic EGFR L858R to antibody-based inhibition. These findings underline the critical relevance of post-translational modifications on oncogene function., Competing Interests: Conflict of Interest Statement The authors declare no potential conflicts of interest

Introduction: Osimertinib is an oral, third-generation, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that selectively inhibits both EGFR-TKI–sensitizing and EGFR T790M resistance mutations. However, whether patients with EGFR mutations can be treated by osimertinib in combination with conventional therapies, remains unknown.Case presentation: We treated a 67-year-old female diagnosed with non-small-cell lung cancer with an EGFR 21 exon L858R–positive mutation. The patient was treated with 80 mg orally administered osimertinib daily, 830 mg pemetrexed, 120 mg cisplatin, and 500 mg bevacizumab. After two cycles of therapy, the patient’s intrapulmonary lesions shrank from 18 × 24 mm to 16 × 4 mm. Moreover, two cycles of evaluation were PR, and four cycles of confirmation were PR. The patient continued to receive the treatments and tolerated them well.Conclusions: The patient benefited from treatment with osimertinib in combination with chemotherapy and bevacizumab.

Introduction: Osimertinib is an oral, third-generation, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that selectively inhibits both EGFR-TKI–sensitizing and EGFR T790M resistance mutations. However, whether patients with EGFR mutations can be treated by osimertinib in combination with conventional therapies, remains unknown. Case presentation: We treated a 67-year-old female diagnosed with non-small-cell lung cancer with an EGFR 21 exon L858R–positive mutation. The patient was treated with 80 mg orally administered osimertinib daily, 830 mg pemetrexed, 120 mg cisplatin, and 500 mg bevacizumab. After two cycles of therapy, the patient's intrapulmonary lesions shrank from 18 × 24 mm to 16 × 4 mm. Moreover, two cycles of evaluation were PR, and four cycles of confirmation were PR. The patient continued to receive the treatments and tolerated them well. Conclusions: The patient benefited from treatment with osimertinib in combination with chemotherapy and bevacizumab. [ABSTRACT FROM AUTHOR]

ObjectiveThe incidence of early stage multiple primary lung cancer (MPLC) has been increasing in recent years, while the ideal strategy for its diagnosis and treatment remains controversial. The present study conducted genomic analysis to identify a new molecular classification method for accurately predicting the diagnosis and therapy for patients with early stage MPLC.MethodsA total of 240 tissue samples from 203 patients with multiple-non-small-cell lung cancers (NSCLCs) (n = 30), early stage single-NSCLC (Group A, n = 94), and advanced-stage NSCLC (Group B, n = 79) were subjected to targeted multigene panel sequencing.ResultsThirty patients for whom next-generation sequencing was performed on >1 tumor were identified, yielding 45 tumor pairs. The frequencies of EGFR, TP53, RBM10, ERBB2, and CDKN2A mutations exhibited significant differences between early and advanced-stage NSCLCs. The prevalence of the EGFR L858R mutation in early stage NSCLC was remarkably higher than that in advanced-stage NSCLC (P = 0.047). The molecular method classified tumor pairs into 26 definite MPLC tumors and four intrapulmonary metastasis (IM) tumors. A high rate of discordance in driver genetic alterations was found in the different tumor lesions of MPLC patients. The prospective Martini histologic prediction of MPLC was discordant with the molecular method for three patients (16.7%), particularly in the prediction of IM (91.7% discordant).ConclusionsComprehensive molecular evaluation allows the unambiguous delineation of clonal relationships among tumors. In comparison, the Martini and Melamed criteria have notable limitations in the recognition of IM. Our results support the adoption of a large panel to supplement histology for strongly discriminating NSCLC clonal relationships in clinical practice.

Objective: The incidence of early stage multiple primary lung cancer (MPLC) has been increasing in recent years, while the ideal strategy for its diagnosis and treatment remains controversial. The present study conducted genomic analysis to identify a new molecular classification method for accurately predicting the diagnosis and therapy for patients with early stage MPLC. Methods: A total of 240 tissue samples from 203 patients with multiple-non-small-cell lung cancers (NSCLCs) (n = 30), early stage single-NSCLC (Group A, n = 94), and advanced-stage NSCLC (Group B, n = 79) were subjected to targeted multigene panel sequencing. Results: Thirty patients for whom next-generation sequencing was performed on >1 tumor were identified, yielding 45 tumor pairs. The frequencies of EGFR, TP53, RBM10, ERBB2 , and CDKN2A mutations exhibited significant differences between early and advanced-stage NSCLCs. The prevalence of the EGFR L858R mutation in early stage NSCLC was remarkably higher than that in advanced-stage NSCLC (P = 0.047). The molecular method classified tumor pairs into 26 definite MPLC tumors and four intrapulmonary metastasis (IM) tumors. A high rate of discordance in driver genetic alterations was found in the different tumor lesions of MPLC patients. The prospective Martini histologic prediction of MPLC was discordant with the molecular method for three patients (16.7%), particularly in the prediction of IM (91.7% discordant). Conclusions: Comprehensive molecular evaluation allows the unambiguous delineation of clonal relationships among tumors. In comparison, the Martini and Melamed criteria have notable limitations in the recognition of IM. Our results support the adoption of a large panel to supplement histology for strongly discriminating NSCLC clonal relationships in clinical practice. [ABSTRACT FROM AUTHOR]

Tyrosine kinase inhibitors are used as first‐line treatment for non‐small cell lung cancer (NSCLC) patients harboring driver mutations in EGFR, ALK, ROS1, and BRAF. Currently, standard molecular testing approaches help identify single genes for such targetable driver mutations in NSCLC; however, next‐generation sequencing (NGS)‐based genetic profiling provides a more comprehensive approach and is hence strongly recommended. This case study aimed to highlight the benefits of NGS‐based tests for the diagnosis of complex EGFR L858R mutations. A patient was diagnosed with stage IVB NSCLC using a government‐approved in vitro diagnostic test and was noted to have a high programmed death‐ligand 1 tumor proportion score. This patient was treated with pembrolizumab monotherapy followed by cisplatin and pemetrexed owing to the lack of actionable driver gene mutations, including EGFR mutations. After treatment failure, a sample harvested from the same transbronchial lung biopsy specimen (formalin‐fixed and paraffin‐embedded) used for the initial EGFR test was subjected to NGS‐based broad genetic profiling. The NGS‐based test identified an EGFR L858R‐K860I cis doublet mutation; however, neither of these mutations was identified upon initial molecular testing. The patient was then successfully treated with a third‐generation EGFR‐tyrosine kinase inhibitor, osimertinib. In this study, we delved deeper into the realm of L858R and K860I mutations in NSCLC and discuss the potential causes underlying our initial negative diagnosis. Furthermore, this study highlighted the additional benefits of replacing typical molecular tests with NGS‐based broad profiling approaches. Key points: Significant findings of the study: The EGFR L858R‐K860I cis doublet mutation was not detected by a PCR‐based EGFR test.A next generation sequencing (NGS)‐based test was able to identify the L858R‐K860I cis doublet mutation. What this study adds: Osimertinib was effective in an NSCLC patient with EGFR L858R and K860I mutations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel compounds were evaluated as inhibitors targeting EGFR primary mutants (L858R, Del19) and drug-resistant mutant T790M. • Both enzymatic and cellular assays led to the identification of compound 7o. • 7o exhibited potent antitumor effects on NSCLC in vitro and in vivo. In this study, we identified a newly synthesized compound 7o with potent inhibition on EGFR primary mutants (L858R, Del19) and drug-resistant mutant T790M with nanomolar IC 50 values. 7o showed strong antiproliferative effects against EGFR mutant-driven non-small cell lung cancer (NSCLC) cells such as H1975, PC-9 and HCC827, over cells expressing EGFRWT. Molecular docking was performed to investigate the possible binding modes of 7o inside the binding site of EGFRL858R/T790M and EGFRWT. Analysis of cell cycle evidenced that 7o induced cell cycle arrest in G1 phases in the EGFR mutant cells, H1975 and PC-9, which resulted in decreased S-phase populations. Moreover, compound 7o induced cancer cell apoptosis in in vitro assays. In addition, 7o inhibited cellular phosphorylation of EGFR. In vivo , oral administration of 7o caused rapid tumor regression in H1975 xenograft model. Therefore, 7o might deserve further optimization as cancer treatment agent for EGFR mutant-driven NSCLC. [ABSTRACT FROM AUTHOR]

Highlights • Leptomeningeal metastasis (LM) has become increasingly common in NSCLC patients. • Data are limited about the effect of EGFR TKI on the development of LM. • We retrospectively evaluated 420 patients treated with first-generation EGFR TKI. • Primary mutation of L858R mark higher risk of LM compared with exon 19 deletions. • It highlights the importance of mutation status to biological behaviors of LM. Abstract Objective To evaluate the influence of a first-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) treatment on the clinical features of leptomeningeal metastasis (LM) progression and outcome in advanced non-small cell lung cancer (NSCLC) patients. Methods We retrospectively evaluated advanced NSCLC patients receiving effective first-generation EGFR TKI treatment (e.g. , treatment > 6 months) at our institution between January 2008 and February 2014. Incidence, time to progression, and treatment outcome of LM were examined. Results In our cohort, 29/420 patients (6.9%) developed LM. Among the patients harboring L858R or deletion of exon 19 in EGFR , the incidence of LM was 10.7% (21/197) and 3.4% (7/203), respectively (P = 0.006). The median time to LM progression was 16.5 months (95% confidence interval (CI), 11.9–20.8). The median overall survival (OS) after LM diagnosis was 5.2 months (95% CI, 3.2–7.2). In a subgroup analysis, OS was improved in patients with performance status (PS) ≤ 2 vs. PS > 2 (14.2 months vs. 2.3 months, respectively; P < 0.001). OS was also improved among patients who received, rather than did not receive, anti-tumor treatment (6.0 months vs. 1.9 months, respectively; P < 0.001) or whole brain radiotherapy (WBRT) (6.0 months vs. 3.9 months, respectively; P = 0.038). Multivariate analysis indicated that WBRT is a good prognostic factor (P = 0.048), whereas best support care (P = 0.033) and PS > 2 (P = 0.034) were poor prognostic factors. Conclusion A greater incidence of LM was observed in NSCLC patients harboring EGFR mutations after effective EGFR TKI treatment. In particular, the primary mutation, L858R, potentially predicts a higher risk of LM compared with deletion of exon 19. These results highlight the importance of determining mutation status when evaluating the biological behavior of LM in NSCLC patients who positively respond to EGFR TKI treatment. [ABSTRACT FROM AUTHOR]

The tyrosine kinase inhibitors (TKI) against epidermal growth factor receptor ( EGFR ) are generally utilized as a part of patients with non-small cell lung carcinoma (NSCLC). However, EGFR T790M mutation results in resistance to most clinically available EGFR TKIs. Third-generation EGFR TKIs against the T790M mutation has been in active clinical development to triumph the resistance problem; they covalently bind with conserved Cys797 inside the EGFR active site, offering both potency and kinase-selectivity. Third generation drugs target C797, which makes the C797S resistance mutation more subtle. EGFR C797S mutation was accounted to be a main mechanism of resistance to the third-generation inhibitors. The C797S mutation gives off an impression of being an ideal target for conquering the acquired resistance to the third generation inhibitors. We have performed structure based-virtual screening strategies for binding of glucokinase activator to EGFR C797S, which can overcome EGFR resistance impediment with mutant-selective allosteric inhibition towards all kinds of mutant EGFR (T790M, L858R, TMLR) and WT EGFR. The final filter of Lipinski’s Rule of Five, Jargan’s Rule of Three and in silico ADME predictions gave 23 hits, which conform to Lipinski’s rule and Jorgensen’s rule and all their pharmacokinetic parameters are inside the appropriate range characterized for human use, in this manner demonstrating their potential as a drug-like molecule. [ABSTRACT FROM AUTHOR]

Lung cancer remains one of today’s most deadly and intractable cancers. Non-small cell lung cancer (NSCLC) accounts for roughly 85% of lung cancers, with an extremely poor survival rate. To ensure patient comfort and survival, the development of a selective therapy is imperative. However, lung cancer does not display surface proteins associated uniquely with tumor cells; thus, it is very difficult to develop a tumor-specific drug. Current techniques that target overexpression of proteins or inhibit growth pathways are either non-specific or prone to rapid drug resistance. The goal was to design a drug targeted to structural mutations expressed by tumor-associated general surface proteins, thereby combating the lack of tumor-unique markers in lung cancer. Mutant EGFR was identified as a potential target due to its prominence in tumor cells. Due to their size, it was determined that small molecules would be most effective at targeting isolated changes in protein structure, and thereby differentiating between the tumor-associated mutant EGFR and the healthy wild type. Conformational analysis of a virtual binding study conducted in VINA predicted a set of drug-like small molecules specific for the L858R mutation in EGFR. One molecule (ZN47) was then acquired and conjugated to a carrier protein to form a multifaceted hapten–protein conjugate. Multiple ELISAs were conducted to confirm the specificity of the conjugate to both tumor-associated mutant EGFRs. The results indicate that the identified molecule may be highly selective for tumor-associated L858R-EGFR, but further research, including a complete dosage-binding study, is necessary for full validation.

Lung cancer with EGFR mutation is often associated pathological characteristics and good responses to EGFR tyrosine kinase inhibitors (TKIs). However, certain types of rare EGFR mutations have be linked to cases with poor response to EGFR TKIs. Therefore, extensive molecular screening and pathological characterization are essential for accurate diagnosis and selection of effective treatment plans. Although a large body of studies have established the rate of EGFR mutations as a whole entity, the rates of each individual types of mutations, especially those rare ones, have not been precisely determined in large patient populations with uniform genetic background. To address this issue, we assembled a large cohort of 456 Chinese patients with lung cancers to determine the rate of both common and rare forms of EGFR mutations and associated clinicopathological features in this retrospective study. We have found single or double EGFR mutations in 200 (43.9%) patients, including exon 19 deletions (E19del) (20%), exon 21 L858R (17.1%) and L861Q (1.5%) point mutations, exon 20 T790M (1.3%) and other mutations (1,3%), exon 18 mutations (1.3%), and double mutations (1.3%). EGFR mutation as well as its subtypes E19del, L858R, or double mutations were associated with female patients or never-smokers. In contrast, rare mutations, especially EGFR TKI resistant exon 20 mutations, were not statistically associated with any clinicopathological features, implicating that tumorigenesis driven by different EGFR mutations were mechanistically different. In summary, we have determined occurring rate of EGFR subtype mutations and demonstrated that different mutations showed different clinicopathological manifestations in lung cancer. [ABSTRACT FROM AUTHOR]

Lung cancer remains one of today's most deadly and intractable cancers. Non-small cell lung cancer (NSCLC) accounts for roughly 85% of lung cancers, with an extremely poor survival rate. To ensure patient comfort and survival, the development of a selective therapy is imperative. However, lung cancer does not display surface proteins associated uniquely with tumor cells; thus, it is very difficult to develop a tumor-specific drug. Current techniques that target overexpression of proteins or inhibit growth pathways are either non-specific or prone to rapid drug resistance. The goal was to design a drug targeted to structural mutations expressed by tumor-associated general surface proteins, thereby combating the lack of tumor-unique markers in lung cancer. Mutant EGFR was identified as a potential target due to its prominence in tumor cells. Due to their size, it was determined that small molecules would be most effective at targeting isolated changes in protein structure, and thereby differentiating between the tumorassociated mutant EGFR and the healthy wild type. Conformational analysis of a virtual binding study conducted in VINA predicted a set of drug-like small molecules specific for the L858R mutation in EGFR. One molecule (ZN47) was then acquired and conjugated to a carrier protein to form a multifaceted hapten-protein conjugate. Multiple ELISAs were conducted to confirm the specificity of the conjugate to both tumor-associated mutant EGFRs. The results indicate that the identified molecule may be highly selective for tumor-associated L858R-EGFR, but further research, including a complete dosage-binding study, is necessary for full validation. [ABSTRACT FROM AUTHOR]

Objective Previous studies have indicated that EGFR exon 19 deletions in non-small cell lung cancer (NSCLC) are associated with better outcomes to tyrosine kinase inhibitors (TKIs) than the L858R mutation. This study aimed to evaluate whether T790M, a resistant mutation, is more likely to coexist with L858R mutation than with exon 19 deletions in pretreatment NSCLC patients. Materials and method We searched MEDLINE and EMBASE up to Nov 30th, 2015 to identify randomized controlled trials (RCTs) and observational studies that reported pretreatment T790M and EGFR-activating mutation. A meta-analysis was performed using a random-effects model. The primary outcome was odds ratio (OR) of pretreatment T790M mutation in NSCLC co-existing with L858R mutation and exon 19 deletions. Stratified analysis was performed based on sensitivity of mutation detection methods for T790M. Results We identified 15 observational studies and 3 RCTs for analysis. Pretreatment T790M was more frequent in L858R than in exon 19 mutated patients. The association of T790M and L858R was statistically significant in observational studies (OR, 1.65, 95% CI, 1.17–2.32), with less precision in RCTs (OR, 1.84, 95% CI, 0.96–3.52). In the stratified analysis based on the sensitivity of the mutation detection methods, the association was observed in the studies using intermediately (detection limit <5% and ≥0.1%; OR, 2.23, 95% CI, 1.19–4.17) and highly sensitive methods (detection limit <0.1%; OR, 1.74, 95% CI, 1.10–2.73), but not in those using low sensitivity methods (detection limit >5%; OR, 1.28, 95% CI, 0.74–2.23). Conclusions Pretreatment EGFR T790M mutation is more likely to coexist with L858R mutation than with exon 19 deletions in NSCLC. This association was observed only in studies using sensitive mutation detection methods (<5%). [ABSTRACT FROM AUTHOR]

Background: Two types of epidermal growth factor receptor (EGFR) mutations in exon 19 and exon 21 (ex19del and L858R) are prevalent in lung cancer patients and sensitive to targeted EGFR inhibition. A resistance mutation in exon 20 (T790M) has been found to accompany drug treatment when patients relapse. These three mutations are valuable companion diagnostic biomarkers for guiding personalized treatment. Quantitative polymerase chain reaction (qPCR)- based methods have been widely used in the clinic by physicians to guide treatment decisions. The aim of this study was to evaluate the technical and clinical sensitivity and specificity of the droplet digital polymerase chain reaction (ddPCR) method in detecting the three EGFR mutations in patients with lung cancer. Methods: Genomic DNA from H1975 and PC-9 cells, as well as 92 normal human blood specimens, was used to determine the technical sensitivity and specificity of the ddPCR assays. Genomic DNA of formalin-fixed, paraffin-embedded specimens from 78 Chinese patients with lung adenocarcinoma were assayed using both qPCR and ddPCR. Results: The three ddPCR assays had a limit of detection of 0.02% and a wide dynamic range from 1 to 20,000 copies measurement. The L858R and ex19del assays had a 0% background level in the technical and clinical settings. The T790M assay appeared to have a 0.03% technical background. The ddPCR assays were robust for correct determination of EGFR mutation status in patients, and the dynamic range appeared to be better than qPCR methods. The ddPCR assay for T790M could detect patient samples that the qPCR method failed to detect. About 49% of this patient cohort had EGFR mutations (L858R, 15.4%; ex19del, 29.5%; T790M, 6.4%). Two patients with the ex19del mutation also had a naïve T790M mutation.Conclusion: These data suggest that the ddPCR method could be useful in the personalized treatment of patients with lung cancer [ABSTRACT FROM AUTHOR]

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Mutant allele frequency (MAF) of 9% was proposed to be the threshold value of pyrosequencing in L858R detection. The MAF predicts the efficacy of EGFR-TKI therapy in patients with advanced lung adenocarcinoma harboring the L858R. Although, the true-positive results must be detected using a highly sensitive method, this would have required setting a cut-off value for the mutation quantitatively.Background Whether the mutant allele frequency (MAF) may also have predictive implications for tyrosine kinase inhibitor (TKI) therapy in patients with advanced epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma (AELAd) remains unknown. Patients and methods Based on a biobanking system in conjunction with our institution, we assessed EGFR mutation status using pyrosequencing (Py) and by outsourcing laboratory tests, such as the Cycleave (Cy) and the Scorpion ARMS (A). Results Out of 705 patients enrolled in the Shizuoka Lung Cancer Mutation Study between July 2011 and March 2013, 102 AELAd patients were identified as carrying the L858R mutation (L858Rm) using Py to analyze histological specimens. Of these 102 patients, the EGFR mutation status was assessed using both Py and Cy in 48 patients: the median MAF of L858R (MAFLR) was 18.5% (range: 8%–82%), and 45 patients (94%) were identified as having an L858Rm using both Py and Cy. Three patients (6%) with discrepant L858Rm findings were only identified using Py. The plotting of a receiver operating characteristic curve to identify the discordance in L858Rm findings showed that the area under the curve for MAFLR was 0.967 (95% confidence interval: 0.91–1) and that an MAFLR of 9% resulted in high sensitivity (100%) and specificity (99%). Also, 29 patients with AELAd, excluding those with postoperative recurrences, had their L858R status assessed using Cy or A. The median age, 69 years (range: 47–84 years); male/female, 14 (48%)/15 (52%); smokers/never-smokers 13 (45%)/16 (55%); ECOG PS 0–1/2–3, 26 (90%)/3 (10%); stage IIIB/IV, 4 (14%)/25 (86%); median MAFLR, 18% (range: 8%–63%). Patients with an MAFLR of ≤9% had a significantly shorter progression-free survival (PFS) period after TKI therapy than those with an MAFLR of >9% (mPFS: 92 versus 284 days, P = 0.0027). Conclusion The MAF may be a potential predictive factor of TKI treatment efficacy in patients with AELAd carrying the L858Rm. [ABSTRACT FROM AUTHOR]

Purpose: Subclones bearing the epidermal growth factor receptor (EGFR) T790M mutation concomitant with deletional mutation in exon 19 (Del19) or a point mutation in exon 21 (L858R) have been reported in non-small cell lung cancer patients before any EGFR tyrosine-kinase inhibitor (TKI) treatment. The effect of pretreatment T790M mutation on the survival of patients with both mutations treated with EGFR TKI is still being debated. Methods: A meta-analysis was undertaken to pool eligible trials to better elucidate whether pretreatment T790M mutation predicts a poorer outcome of EGFR TKI treatment. Hazard ratios and their 95% confidence intervals for progression-free survival (PFS) were extracted and used under the random-effects model. Results: A total of 246 patients with activating EGFR mutation such as Del19 or L858R participated in four selected trials from 350 articles. The overall incidence of patients with pretreatment T790M mutation was 43.10% (106/246), ranging from 34.88% to 80.00% in the individual trials. The combined hazard ratio for PFS in all four eligible studies was 2.602 (95% confidence interval 1.011-6.695; P=0.047), indicating a shorter PFS in patients who had the T790M mutation before receiving EGFR TKI treatment. Heterogeneity testing indicated significant heterogeneity but the absence of publication bias. Conclusion: The meta-analysis reported here found that pretreatment T790M mutation had a negative impact on the PFS of non-small cell lung cancer patients with a Del19 or L858R EGFR mutation who received EGFR TKI treatment [ABSTRACT FROM AUTHOR]

Overall benefits of EGFR-TKIs are limited because these treatments are largely only for adenocarcinoma (ADC) with EGFR activating mutation. The treatments also usually lead to development of resistances. We have established a panel of patient-derived xenografts (PDXs) from treatment naïve Asian NSCLC patients, including those containing 'classic' EGFR activating mutations. Some of these EGFR-mutated PDXs do not respond to erlotinib: LU1868 containing L858R/T790M mutations, and LU0858 having L858R mutation as well as c-MET gene amplification, both squamous cell carcinoma (SCC). Treatment of LU0858 with crizotinib, a small molecule inhibitor for ALK and c-MET, inhibited tumor growth and c-MET activity. Combination of erlotinib and crizotinib caused complete response, indicating the activation of both EGFR and c-MET promote its growth/survival. LU2503 and LU1901, both with wild-type EGFR and c-MET gene amplification, showed complete response to crizotinib alone, suggesting that c-MET gene amplification, not EGFR signaling, is the main oncogenic driver. Interestingly, LU1868 with the EGFR L858R/T790M, but without c-met amplification, had a complete response to cetuximab. Our data offer novel practical approaches to overcome the two most common resistances to EGFR-TKIs seen in the clinic using marketed target therapies. [ABSTRACT FROM AUTHOR]

Summary: Mucoepidermoid carcinoma (MEC) of lung is a rare malignancy of lung which originates from minor salivary glands of tracheobronchial tree. EGFR targeted therapy by inhibition of EGFR activation with the specific tyrosine kinase inhibitors (TKIs) has shown meaningful anti-tumor activity in patients with EGFR TK mutation and/or amplification, or in patients with adenocarcinoma. In the present study, we find that MEC has EGFR mutation in 40% (2 out of 5) of cases, and all mutations are L858R mutation. In addition, we also observed that a MEC patient well-responded to EGFR TKI in the absence of EGFR mutation or amplification. These data indicate for the first time that MEC of lung is another potential target of EGFR inhibitor, and more extended clinical investigation is warranted. [Copyright &y& Elsevier]

Summary: Purpose: Epidermal growth factor receptor (EGFR) mutations have been found in the majority of gefitinib-responsive non-small cell lung cancer (NSCLC) patients from retrospective studies. We sought to compile the available phase II and prospective trials of this EGFR tyrosine kinase inhibitor (TKI) to better understand the efficacy and safety of selecting patients to receive gefitinib based on their genotype. Design: We searched published trials involving EGFR-mutant patients and gefitinib. Five reports were identified (published between June 2006 and April 2007) in which gefitinib was given in a prospective manner to EGFR mutation positive patients at a dose of 250mg/day. Responses were determined by RECIST and toxicities by NCI-CTC. Results: A total of 101 patients were pooled from these studies. Fifty-nine received gefitinib as their first line of therapy and 42 after having received chemotherapy. The combined rate of complete and partial response (CR+PR) in the 99 measured patients was 80.8% (80/99) and only 7.1% (7/99) had progressive disease as best response. The response rate (CR+PR) for exon 19 deletion and L858R patients were 80.3% (53/66) and 81.8% (27/33), respectively. The median progression-free survival ranged from 7.7 to 12.9 months. Overall survival had not been reached in 4/5 reports and was 15.4 months in one of them. Gefitinib administration was safe (<50% of patients developed grades 1–2 skin rash or diarrhea) and interstitial lung disease was only reported in two patients (2%), without deaths. Conclusions: Gefitinib monotherapy leads to objective responses in most patients with EGFR mutations. Both L858R and deletion 19 mutations derived similar clinical benefits. Small molecule TKIs are the new treatment paradigm for EGFR-mutant NSCLC. [Copyright &y& Elsevier]

Summary: Somatic mutations of the epidermal growth factor receptor (EGFR) gene were found in about 25–40% of Japanese lung cancer patients. These mutations are associated with clinical and radiographic responses to EGFR tyrosine kinase inhibitors. Most common mutation are arginine for leucine substitution at amino acid 858 (L858R) and exon 19 deletions, especially deletion type 1 mutation. We investigated these EGFR mutation statuses in 575 surgically treated non-small cell lung cancer (NSCLC) cases. Three-hundred and sixty-two adenocarcinoma cases were included. The presence or absence of EGFR mutations of kinase domains was analyzed by genotyping analysis (TaqMan assay; n =386, and LightCycler assay; n =98) and sequences (n =91). EGFR mutations (CTG; CGG; L858R) were found from 63 of 575 lung cancer patients. We also detected the deletion 1a type mutations (2235–2249 del GGAATTAAGAGAAGC) from 39 patients and deletion 1b type mutations (2236–2250 del GAATTAAGAGAAGCA) from 15 patients in exon 19. These mutation statuses were significantly correlated with gender, smoking status (never smoker versus smoker), and pathological subtypes (adenocarcinoma versus non-adenocarcinoma). L858R mutation (p <0.0001), but not deletion 1 type mutation (p =0.0665), was correlated with differentiation status (well versus moderately or poorly) of lung cancers. L858R mutation ratio was significantly higher in non-smoker (p =0.0496) and adenocaicinoma (p =0.0136) when compared to deletion 1 type mutations. The EGFR mutation status, especially L858R mutation might be correlated with the clinico-pathological features related to good response to gefitinib, such as gender, smoking history, and pathological subtypes of Japanese lung cancers. [Copyright &y& Elsevier]

Background: Exon del19 and L858R mutations account for 90% of EGFR mutant non-small cell lung cancer (NSCLC). LUX lung 3 and 6 initially reported a survival difference between these two. However, other studies did not demonstrate the same. By using machine learning (ML), it is possible to discover novel patterns for cancer susceptibility, recurrence, prognostication, and therapy. We evaluate the effect of these two molecular subtypes on overall survival/progression-free survival (OS/PFS)., Methods: 413 patients with stage IV EGFR mutant NSCLC were analyzed for clinicopathologic features, treatment details, and survival outcome. PFS prediction models were built using ensemble decision trees, and random forest. Ensemble decision trees were built and validation was performed using survival analysis. Clustering regression techniques were then applied to train and test the prediction of the 1 st PFS of patients., Results: The median age of the cohort was 59 years comprising 53% males and 47% females. 275 (66.5%) patients showed a del19 mutation type and 138 (33.5%) harbored L858R. After clustering, the most important variables were age (P<0.05), ECOG performance status (PS) (P<0.04), PDL1 (P<0.09), smoking status (P<0.01) and to a lesser extent, number of extrathoracic metastasis (ETM) sites (median 1.2, P<0.06), brain metastasis (P<0.06) and gender (P<0.08). The prediction for 1 st PFS for del19 showed mean absolute error of 2.6 months and 4.72 months for L858R. The accuracy was 79.8% with 82% sensitivity, 79% specificity and AUC: 0.72. The precision was 92% with a Mathews correlation coefficient of 0.59., Conclusion: This study used machine learning modeling with fair accuracy to demonstrate that ECOG PS, age at diagnosis, and smoking status are the three main predictive factors of PFS in these patients., Competing Interests: None., (AJTR Copyright © 2022.)

Objective: Non-Small Cell Lung Cancer (NSCLC) Carcinogenesis could be caused by numerous genetic mutations, one of the most common is the mutation in the Epidermal Growth Factor Receptor (EGFR) which was used in the advanced stages of the disease as a therapeutic goal. This study aim to estimate the frequency of Epidermal Growth Factor Receptor mutations in Iraqi patients with Non-Small Cell Lung Cancer., Methods: One hundred thirty-eight patients confirmed with NSCLC have participated in this study, patients were sent for EGFR testing by different oncology centers in Iraq. Data and samples were collected. The Mutation was detected using COBAS® DNA Sample Preparation Kit that designed to detect the following mutations: Exon 19: deletions and complex mutations; Exon 21: L861Q and L858R; Exon 18 mutation: G719X (G719A, G719C, and G719S); Exon 20: S768I, T790M, and insertions, this kit utilizes the technology of the real time Polymerase Chain Reaction., Results: This study was included 79 males and 59 females, with a mean age of 60.1±12.4 years. A positive EGFR mutations were found in 38 (27.53%) of samples. Exon 19 deletions (25/38, 65.8%) and substitution L858R in exon 21 10/38 (26.3%) were the most common mutations. Multiple mutations (Exon 20 and 19 combined together) were founded in 2/38 (5.3%), 1/38 (2.6%) ALK mutation. Non-significant differences among age groups and gender in the incidence of mutations were found., Conclusion: The current study represents the first epidemiological study in Iraq to find EGFR mutations frequency among NSCLC patients that reveals the incidence rate of 27.53%, which is between the higher prevalence rate in Asian populations and lower rates in western countries. These results explain the genetic differences of NSCLC in the world due to ethnic differences of the population, more studies are needed in Arab countries to study the EGFR mutations, find the effect of ethnicity and environmental factors for lung cancer, and the subsequent therapy.

Background: To understand the association between driver gene variations and age and gender in patients with lung adenocarcinoma, we investigated mutations of the three most important driver genes-epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK) fusion genes and c-ros oncogene 1 (ROS1)-in this retrospective cohort study., Methods: Patients newly diagnosed with lung adenocarcinoma who received EGFR and ALK/ROS1 gene tests at our hospital from September 2014 to May 2019 were enrolled. EGFR mutations and ROS1 fusions were examined by ARMS-PCR and ALK fusions by Ventana-D5F3 IHC assay and ARMS-PCR., Results: Of 2544 eligible subjects, 2539 accomplished EGFR mutation tests. The prevalence of EGFR mutations was 62.1% in females, higher than that of 45.1% in males. In females, the EGFR mutation rate remained relatively stable at 60%-65% across the six age groups. Females showed an increased distribution of EGFR L858R and a decreased distribution of exon 19 deletion (19Del) by age. The incidence of ALK/ROS-1 rearrangements decreased significantly with age., Conclusions: EGFR 19Del mutation is more prevalent in younger males and females, while L858R mutation is prevalent in older females. Both ALK and ROS1 rearrangements are more common in younger lung adenocarcinoma. The young lung adenocarcinoma population is a distinct group rich in targetable genomic alterations, and more research is needed to understand the mechanism.

A de novo single-nucleotide mutation in the EGFR gene can cause the development of lung cancer. EGFR tyrosine kinase inhibitors (EGFR-TKIs) are used for clinical treatment of such lung cancers, but acquired resistance often mitigates their efficacy. Accordingly, monitoring of de novo and acquired nucleotide mutations is essential for clinical treatment of lung cancers with EGFR-TKIs. Previously, we reported that oligoribonucleotide interference-PCR (ORNi-PCR) can accurately and cost-effectively detect single-nucleotide mutations. In this study, we applied ORNi-PCR to simultaneous detection of the de novo L858R and acquired T790M mutations in the EGFR gene in lung cancer cells. First, we established optimal experimental conditions for ORNi-PCR to simultaneously detect the two single-nucleotide mutations in genomic DNA from lung cancer cells. The conditions we established could also be used for ORNi-PCR using complementary DNA reverse-transcribed from extracted RNA. We found that ORNi-PCR could detect lung cancer cells possessing both single-nucleotide mutations among a large number of cells harboring wild-type sequences, even when the cancer cells constituted less than ~0.2% of all cells. Our findings demonstrate that ORNi-PCR can simultaneously detect multiple single-nucleotide mutations in a gene of interest and might therefore be useful for simultaneous detection of EGFR mutations in clinical examinations. [ABSTRACT FROM AUTHOR]