Epidermal Growth Factor Receptor Gene Copy Number Research Articles

The association of EGFR amplification with aberrant exon 20 insertion report using the cobas EGFR Mutation Test v2.

Determining the exact type of epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutation in lung cancer has become important. We found that not all ex20ins mutations reported by cobas EGFR test v2 could be validated by Sanger sequencing even using surgical specimens with high tumor contents. This study aimed to validate the ex20ins results reported by the cobas test and to determine whether there were clinicopathological factors associated with aberrant cobas ex20ins report. In total, 123 cobas-reported cases with ex20ins were retrospectively collected and validated by Sanger sequencing and Idylla assay. Clinicopathological features between ex20ins cobas+/Sanger+ group (n = 71) and cobas+/Sanger- group (n = 52) were compared. The Idylla assay detected ex20ins in 82.6% of cobas+/Sanger+ cases but only in 4.9% of cobas+/Sanger- cases. The cobas+/Sanger- group was significantly associated with higher tumor contents, poorly differentiated patterns, tumor necrosis, and a lower internal control cycle threshold value reported by the Idylla which suggesting the presence of increased EGFR gene copy numbers. EGFR fluorescence in situ hybridization (FISH) revealed the majority of cobas+/Sanger- group had EGFR high copy number gain (16%) or amplification (76%) according to the Colorado criteria. Among cases reported to have concomitant classic EGFR and ex20ins mutations by the cobas, the classic EGFR mutations were all detected by Sanger sequencing and Idylla, while the ex20ins mutations were undetected by Sanger sequencing (0%) or rarely reported by Idylla assay (3%). FISH revealed high EGFR copy number gain (17.9%) and amplification (79.5%) in cases reported having concomitant classic EGFR and ex20ins mutations by the cobas. This study demonstrated an unusually high frequency of EGFR amplification in cases with aberrant cobas ex20ins report which could not be validated by Sanger sequencing or Idylla assay. Ex20ins reported by the cobas test should be validated using other methods especially those reported having concomitant ex20ins and classic EGFR mutations.

Abstract CT156: MCLA-158 (petosemtamab), an IgG1 bispecific antibody targeting EGFR and LGR5, in advanced gastric/esophageal adenocarcinoma (GEA)

Abstract The epidermal growth factor receptor (EGFR) is a known driver of cancer growth and the leucine-rich, repeat-containing, G-protein coupled receptor 5 (LGR5) is a transmembrane receptor expressed on cancer stem cells. Petosemtamab is a human, common light chain, IgG1 bispecific antibody with enhanced ADCC activity targeting EGFR and LGR5, which has shown potent antitumor activity in patient (pt)-derived xenograft models of gastric and esophageal cancer. The dose escalation part of an ongoing phase 1/2 study is completed (JCO 2021:39.3 Sup 62). In the expansion part, petosemtamab is being investigated at the RP2D (1500 mg Q2W, 4-week cycle) in pts with selected advanced solid tumors, including GEA. Primary objective (expansion): investigator-assessed ORR per RECIST 1.1. Secondary objectives: ORR, DOR, PFS (per investigator and central review), OS, and safety and tolerability. Key eligibility criteria: advanced/metastatic GEA, prior exposure to ≥2 lines of standard therapy, ECOG PS 0-1, measurable disease (RECIST 1.1), available baseline tumor biopsy. At the data cutoff date of 24 October 2022, 14 GEA pts were treated at the RP2D. Median age was 63 years (range 40-80), ECOG PS 0/1: 3/11 pts, and 79% of pts were male. Primary tumor locations were esophagus (57%), stomach (36%), and gastroesophageal junction (7%), and all were adenocarcinoma histology. Pts received a median of 3 lines of prior systemic therapy (range 1-4) including platinum-based chemotherapy (100%) and checkpoint inhibitors (14%). 3/14 pts had EGFR overexpression (H score ≥200). A median of 2 treatment cycles (range 1-24) was administered, with 1 pt continuing therapy at the cutoff. Among the 14 pts evaluable for efficacy (≥2 cycles and ≥1 postbaseline scan, or early progression) limited activity was seen, however 1 pt with tumor EGFR protein overexpression and gene copy number amplification (CNA) showed a confirmed sustained PR (67% tumor reduction; response ongoing after 24 cycles) and 3 pts had SD (1 with EGFR overexpression and gene CNA; 2 not evaluable for IHC), with tumor reductions of 2%, 17%, and 40%. Among 78 pts treated at the RP2D (escalation and all expansion cohorts; cutoff 28 November 2022), the most frequent AEs regardless of causality (all grades/G3-4) were rash (33%/0%), hypotension (26%/6%), dyspnea (26%/4%), nausea (26%/1%), dermatitis acneiform (24%/1%), blood magnesium decreased (19%/5%), erythema (19%/0%), diarrhea (19%/0%); IRRs (composite term) were reported in 74%/21% of pts, mostly at the first infusion, and all resolved. 5 pts (6%) discontinued treatment due to IRRs on Day 1. 1 esophageal cancer pt died due to unrelated G5 GI bleeding. Petosemtamab demonstrated promising clinical efficacy among patients with pretreated GEA having EGFR gene amplification and/or overexpression, with a manageable safety profile. Citation Format: Marc Díez García, Antoine Hollebecque, Rocio Garcia-Carbonero, Christiane Jungels, Elisabeth Smyth, Shumei Kato, Guillem Argilés, Carlos Gomez Martin, Marina Magin, Yu-Ming Shen, Renée de Leeuw, Mohamed Bekradda, Eduardo Pennella, Ernesto Wasserman, Viktoriya Stalbovskaya, Jeroen Lammerts van Bueren, Aline Engbers, Andrew Joe, Josep Tabernero. MCLA-158 (petosemtamab), an IgG1 bispecific antibody targeting EGFR and LGR5, in advanced gastric/esophageal adenocarcinoma (GEA) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT156.

Prognostic Impact of EGFR Amplification and Visceral Pleural Invasion in Early Stage Pulmonary Squamous Cell Carcinomas Patients after Surgical Resection of Primary Tumor.

Simple SummaryLung cancer is the most prevalent malignant neoplasm worldwide. Pulmonary squamous cell carcinoma (SCC) is a histological subtype of non-small cell lung carcinoma with a high rate of morbimortality. The identification of biomarkers with prognosis value is critical in the follow-up and management of SCC patients. Amplification of Epidermal Growth Factor Receptor (EGFR) gen on 7p12 is frequently found in pulmonary SCC. We analyzed this alteration with immunohistochemistry, and fluorescence in situ hybridization, along with clinic-pathological variables such as gender, age, pT-stage, lymph node status, pleural invasion, stage, recurrence, metastasis, and overall survival, in a homogeneous population of 108 patients. We found that EGFR amplification, exclusively in early stage SCC (pT1–pT2), is an independent adverse prognostic factor for overall survival and combined with visceral pleural invasion, allows the identification of three groups of pulmonary SCC patients with significantly different outcome, which could be established at diagnosis.Over the last few decades, an increasing amount of information has been accumulated on biomarkers in non-small cell lung cancer (NSCLC). Despite these advances, most biomarkers have been identified in the adenocarcinoma histological subtype (AC). However, the application of molecular-targeted therapies in the prognosis and treatment of SCC in the clinical setting is very limited, becoming one of the main focus areas in research. Here, we prospectively analyzed the frequency of numerical/structural abnormalities of chromosomes 5, 7, 8, 9, 13 and 22 with FISH in 48 pulmonary SCC patients. From a total of 12 probes, only abnormalities of the 7p12 and 22q12 chromosomal regions were identified as unique genetic variables associated with the prognosis of the disease. The study for these two chromosomal regions was extended to 108 patients with SCC. Overall, chromosome losses were observed more frequently than chromosome gains, i.e., 61% versus 19% of all the chromosome abnormalities detected. The highest levels of genetic amplification were detected for the 5p15.2, 7p12, 8q24 and 22q11 chromosome bands, of which several genes are potentially involved in the pathogenesis of SCC, among others, include the EGFR gene at chromosome 7p12. Patients who displayed EGFR amplification (n = 13; 12%) were mostly older than 65 years (p = 0.07) and exclusively patients in early T-primary tumor stage (pT1–pT2; p = 0.03) with a significantly shortened overall survival (OS) (p ≤ 0.001). Regarding prognosis, the clinical, biological, and histopathologic characteristics of the disease that displayed a significant adverse influence on OS in the univariate analysis included patients older than 65 years (p = 0.02), the presence of lymph node involvement (p = 0.005), metastasis (p = 0.01) and, visceral pleural invasion (VPI) at diagnosis (p = 0.04). EGFR amplification also conferred an adverse impact on patient OS in the whole series (p = 0.02) and especially in patients in early stages (pT1–pT2; p = 0.01). A multivariate analysis of the prognostic factors for OS showed that the most informative combination of independent variables to predict an adverse outcome was the presence of VPI and/or EGFR amplification (p < 0.001). Based on these two variables, a scoring system was built to stratify patients into low- (no adverse features: score 0; n = 69), intermediate- (one adverse feature: score 1; n = 29) and high-risk (two adverse features: score 2; n = 5) groups, with significantly different (p = 0.001) OS rates at 50 months, which were as following: 32%, 28% and 0%, respectively. In the present study, we show that the presence of a high level of 7p12 (EGFR) amplification, exclusively detected in early stage SCC (pT1–pT2), is an independent adverse prognostic factor for OS. The identification of the EGFR gene copy number using FISH techniques may provide a more accurate diagnosis of high-risk populations after the complete resection of the primary tumor. When combined with VPI, three groups of pulmonary SCC were clearly identified that show the extent of the disease. This is of such importance that further prospective studies are necessary in larger series of SCC patients to be classified at the time of diagnosis. This could be achieved with the combined assessment of 7p12 amplification and VPI in primary tumor samples.

Potential for Using EGFR Expression in Rhabdomyosarcoma, Osteosarcoma and Ewing’s Sarcoma: Clinicopathological and Prognostic Significance

Sarcomas are a heterogeneous group of malignant tumors that arise from mesenchymal cells and can arise anywhere in the body, whether it is soft tissue or bone. Epidermal growth factor receptor (EGFR) expression in pediatric sarcomas is explored in the current study. A key feature of EGFRs is their general involvement in signal transduction and oncogenesis, making them one of the most studied receptor protein-tyrosine kinase families. The study included 104 archived formalin-fixed paraffin-embedded blocks assessed using immunohistochemical stains for EGFR expression in rhabdomyosarcoma, osteosarcoma, and Ewing's sarcoma. EGFR gene copy number was analyzed by dual silver in situ hybridization (DISH). EGFR was positively expressed in 56.7% of pediatric sarcoma. Immunostaining for EGFR was significantly associated with deep large tumors, stage, and histologic grade. Significantly, lower chances of overall survival were observed with elevated levels of EGFR five years post-diagnosis. EGFR staining identified independent risk factors for poor patient outcomes. The results of in situ hybridization did not indicate EGFR gene amplification in any of the cases assessed. EGFR overexpression was an independent predictor of pediatric sarcoma outcome, which is highly associated with histologic grade and stage. Results indicate EGFR inhibitors should be potentiated and directed against pediatric sarcoma. KEYWORDS EGFR, Ewing’s sarcoma, osteosarcoma, rhabdomyosarcoma

Retrospective Study of Cisplatin/Carboplatin, 5-Fluorouracil Plus Cetuximab (EXTREME) for Advanced-stage Salivary Gland Cancer.

Surgery remains the standard treatment for salivary gland carcinoma (SGC). Our study investigated the association between epidermal growth factor receptor (EGFR) status in recurrent/metastatic SGC and the effectiveness of treatment with cisplatin/carboplatin and 5-fluorouracil plus cetuximab (EXTREME). We retrospectively collected 19 SGCs from patients treated with the EXTREME regimen. After analyzing EGFR expression and gene copy number gain, we evaluated the correlation between EGFR status and clinicopathological factors and prognosis. EGFR overexpression was detected in 77.8% cases, but not statistically associated with clinicopathological factors or prognosis. EGFR gene copy number gain was detected in 16.7% cases, and statistically positively correlated with lymph node metastasis (p=0.0291). The best overall response was partial response in two cases, stable disease in 15, and progressive disease in one case. The EXTREME regimen was discontinued in all cases. Our results suggest that SGCs are positive for EGFR protein expression but the response rate to the EXTREME regimen was unremarkable.

Fatty acid synthase mediates high glucose-induced EGFR activation in oral dysplastic keratinocytes.

Recent studies point to the epidermal growth factor receptor (EGFR) as a critical mediator of type 2 diabetes mellitus (T2DM)-induced renal, cardiac, and ocular complications. T2DM is considered a systemic contributing factor in oral carcinogenesis. Similarly, increased EGFR gene copy number and protein expression strongly predict tumor progression. Yet, the impact of hyperglycemia on EGFR activity in oral potentially malignant disorders remains unclear. We recently reported that fatty acid synthase (FASN), a key de novo lipogenic enzyme, mediates EGFR activation in nicotine-treated oral dysplastic keratinocytes. While in non-malignant tissues FASN expression is extremely low, it is frequently upregulated in several cancers, including oral squamous cell carcinoma. The present study was carried out to investigate whether high glucose conditions trigger pro-oncogenic responses in oral dysplastic keratinocytes via FASN-mediated EGFR activation. Cell viability and migration of oral dysplastic keratinocytes were evaluated when exposed to normal (5mM) or high (20mM) glucose conditions in the presence of FASN and EGFR inhibitors. Western blotting was also performed to assess changes in FASN protein expression and EGFR activation. Oral dysplastic keratinocytes exposed to high glucose led to EGFR activation in a FASN-dependent manner. Likewise, high glucose significantly enhanced cell viability and migration in a FASN/EGFR-mediated fashion. Notably, EGFR inhibition by the anti-EGFR monoclonal antibody cetuximab significantly reduced the proliferation of FASN-overexpressing oral dysplastic keratinocytes. These novel findings suggest that FASN may act as a key targetable metabolic regulator of glucose-induced EGFR oncogenic signaling in oral potentially malignant disorders.

HPV-related Sinonasal Carcinoma: Clinicopathologic Features, Diagnostic Utility of p16 and Rb Immunohistochemistry, and EGFR Copy Number Alteration.

The prevalence and prognostic value of human papillomavirus (HPV) infection and epidermal growth factor receptor (EGFR) alteration in sinonasal squamous cell carcinoma (SNSCC) are not known. The reliability of p16 overexpression as a surrogate for HPV infection in SNSCC is also unclear. We investigated the prognostic and diagnostic significances of HPV infection, EGFR alteration, and p16 expression in SNSCC. We analyzed high-risk HPV infection by HPV-RNA in situ hybridization and EGFR gene copy number gain (CNG) by chromogenic in situ hybridization and by determining the protein expressions of p16, Rb, and EGFR by immunohistochemistry in 101 SNSCC cases. HPV infection (n=9, 8.9%) and p16 overexpression (n=15, 14.9%) were associated with better overall survival (P=0.0042 and 0.005, respectively). The HPV cases were located predominantly at the nasal cavity with nonkeratinizing histology and partial loss of Rb. Notably, 40% (6/15) of p16 SNSCCs were HPV. Two of these cases showed complete loss of Rb expression by immunohistochemistry, suggesting a reason for the above discrepancy. EGFR CNG, detected in 30.5% of the SNSCCs, was correlated with EGFR protein overexpression (P=0.0001). HPV infection and EGFR CNG were mutually exclusive. The HPV/EGFR CNG group had significantly better overall survival than the HPV/EGFR CNG and HPV/EGFR CNG groups (P=0.0471 and 0.0343, respectively). Our results suggest that HPV infection is a favorable prognostic marker in SNSCC, but p16 is not a perfect surrogate marker; the Rb expression pattern may improve the diagnostic accuracy. The molecular subclassification of SNSCCs based on HPV infection and EGFR copy number status might provide important information for therapeutic strategies.

&lt;p&gt;Epidermal growth factor receptor (&lt;em&gt;EGFR&lt;/em&gt;) gene alteration and protein overexpression in Malaysian triple-negative breast cancer (TNBC) cohort&lt;/p&gt;

BackgroundEpidermal growth factor receptor (EGFR) is a member of the ErbB family of tyrosine kinase receptor proteins that plays important roles in tumour cell survival and proliferation. EGFR has been reported to be overexpressed in up to 78% of triple-negative breast cancer (TNBC) cases suggesting it as a potential therapeutic target. The clinical trials of anti-EGFR agents in breast cancer showed low response rates. However, a subgroup of patients demonstrated response to EGFR inhibitors highlighting the necessity to stratify patients, who might benefit from effective combination therapy that could include anti EGFR-agents. Population variability in EGFR expression warrants systematic evaluation in specific populations.PurposeTo study EGFR alterations and expressions in a multi ethnic Malaysian TNBC patient cohort to determine the possibility of using anti-EGFR combinatorial therapy for this population.Patients and methodsIn this study, we evaluated 58 cases of Malaysian TNBC patient samples for EGFR gene copy number alteration and EGFR protein overexpression using fluorescence in-situ hybridization (FISH) and immunohistochemistry (IHC) methods, respectively.ResultsEGFR protein overexpression was observed in about 30% while 15.5% displayed high EGFR copy number including 5.17% gene amplification and over 10% high polysomy. There is a positive correlation between EGFR protein overexpression and gene copy number and over expression of EGFR is observed in ten out of the 48 low copy number cases (20.9%) without gene amplification.ConclusionThis study provides the first glimpse of EGFR alterations and expressions in a multi ethnic Malaysian TNBC patient cohort emphasising the need for the nationwide large scale EGFR expression evaluation in Malaysia.

Development and interlaboratory evaluation of a NIST Reference Material RM 8366 for EGFR and MET gene copy number measurements.

BackgroundThe National Institute of Standards and Technology (NIST) Reference Material RM 8366 was developed to improve the quality of gene copy measurements of EGFR (epidermal growth factor receptor) and MET (proto-oncogene, receptor tyrosine kinase), important targets for cancer diagnostics and treatment. The reference material is composed of genomic DNA prepared from six human cancer cell lines with different levels of amplification of the target genes.MethodsThe reference values for the ratios of the EGFR and MET gene copy numbers to the copy numbers of reference genes were measured using digital PCR. The digital PCR measurements were confirmed by two additional laboratories. The samples were also characterized using Next Generation Sequencing (NGS) methods including whole genome sequencing (WGS) at three levels of coverage (approximately 1 ×, 5 × and greater than 30 ×), whole exome sequencing (WES), and two different pan-cancer gene panels. The WES data were analyzed using three different bioinformatic algorithms.ResultsThe certified values (digital PCR) for EGFR and MET were in good agreement (within 20%) with the values obtained from the different NGS methods and algorithms for five of the six components; one component had lower NGS values.ConclusionsThis study shows that NIST RM 8366 is a valuable reference material to evaluate the performance of assays that assess EGFR and MET gene copy number measurements.

Epidermal growth factor receptor (EGFR) overexpression in triple-negative breast cancer: association with clinicopathologic features and prognostic parameters

IntroductionTriple-negative breast cancers are a poor prognostic group of breast cancers that don’t respond to conventional hormonal and her2neu targeted therapy. A subset of triple-negative breast cancer is known to overexpress epidermal growth factor receptor (EGFR); however prognostic significance of this biomarker has not been widely studied in our population. Therefore, we aimed to evaluate the frequency of EGFR overexpression in triple-negative breast cancer in our setup and its association with prognostic and predictive factors.MethodsWe performed EGFR immunohistochemistry on 150 cases of triple-negative breast cancers. Intensity and percentage of EGFR expression were combined to formulate an EGFR score, that was compared with prognostic features of breast cancer and recurrence status of patients.ResultsPositive EGFR expression was noted in 18.7% ( 28 cases); out of which 16% (24 cases) showed low EGFR expression, whereas high EGFR expression was seen in 2.7% ( 4 cases). No significant association of EGFR expression was noted when compared with various clinicopathological parameters and recurrence status of the patients.ConclusionWe found EGFR protein expression in 18.7% of cases while high expression was seen in only 2.7 % cases of triple-negative breast cancer which may harbor underlying genetic alterations like altered EGFR gene copy number, chromosome 7 copy number or average EGFR gene: chromosome 7 ratio; therefore we suggest that molecular tests like FISH to evaluate these EGFR molecular alterations should be performed in EGFR over expressing triple negative breast cancers in our setup to identify patients that can benefit from anti-EGFR targeted therapy. Moreover, regional difference in EGFR expression (high expression in chinese population compared to our population) are may be due to different underlying genetic alterations in triple-negative breast cancers, further necessitating a need of devising personalized therapeutic protocols for locoregional population.

EGFR gene copy number decreases during anti-EGFR antibody therapy in colorectal cancer

Epidermal growth factor receptor (EGFR) gene copy number (GCN) increase is associated with a favorable anti-EGFR antibody treatment response in RAS wild-type metastatic colorectal cancer. However, there are limited and comparative data regarding the EGFR GCN in primary colorectal cancer tumors and corresponding metastases or the effect of anti-EGFR antibody treatment on EGFR GCN in recurrent disease. In addition, little is known about the potential EGFR GCN changes during anti-EGFR therapy in comparison with other treatment regimens. EGFR GCN was analyzed by EGFR immunohistochemistry-guided silver in situ hybridization in primary and corresponding recurrent local or metastatic tumors from 80 colorectal cancer patients. GCN levels were compared between KRAS wild-type patients having received anti-EGFR therapy and patients having received other forms of treatment after primary surgery. The EGFR GCN decrease between primary and recurrent tumors was more pronounced among the anti-EGFR-treated patients than among patients not treated with anti-EGFR therapy (P = .047). None of the patients experiencing an EGFR GCN increase of at least 1.0 between the primary and recurrent tumors were treated with anti-EGFR antibodies. When including only patients with distant metastases, an EGFR GCN decrease of at least 1.0 was more common among the anti-EGFR-treated patients than among patients not treated with anti-EGFR therapy (P = .028). Our results suggest that anti-EGFR antibody treatment is associated with EGFR GCN decrease between the primary and recurrent colorectal adenocarcinomas, whereas no GCN change is observed among patients receiving other forms of treatment after primary surgery.

Mini Review: Immunohistochemistry Using EGFR-Mutant Specific Antibodies in Non-Small Cell Lung Carcinoma: Accuracy and Reliability

Epidermal growth factor receptor (EGFR) is a predictive biomarker in many solid cancers including non-small cell lung carcinoma (NSCLC). Patients’ responsiveness to therapy is based on the prior determination of EGFR status. Many techniques were used to detect the potential predictive biomarker and considered as gold standards based on molecular genetic techniques as direct sequencing and polymerase chain reaction (PCR). Immunohistochemistry (IHC) using EGFR mutation-specific antibodies were generated as an alternative simple tool to identify EGFR status and its response to tyrosine kinase inhibitors (TKIs). EGFR gene copy number and wild-type EGFR are other parameters which determine the response to TKIs. The aim of this mini-review is to analyze the studies which investigated the IHC EGFR mutation-specific antibodies, in lung adenocarcinoma (ADC), to determine its accuracy and reliability as a pre-selection tool for candidate patients for TKIs therapy as well as the interplay with other EGFR biomarkers which are EGFR gene copy number and the wild-type EGFR in lung NSCLC. The later determine the response to TKIs and their detection methodology is standardized making them good candidates for comparison with the EGFR-mutation.

Epidermal Growth Factor Receptor Gene Amplification Predicts Worse Outcome in Patients With Surgically Resected Nonadenocarcinoma Lung Cancer

PurposeThe aim of the present study was to examine the prognostic role of amplification and increased expression of the epidermal growth factor receptor (EGFR) gene in surgically resected non-adenocarcinoma of non-small cell lung cancer (NA-NSCLC). Materials and MethodsThe present retrospective study included 114 consecutive NA-NSCLC patients with available tumor tissue and survival data. EGFR gene copy number and protein expression were evaluated using fluorescent in situ hybridization (FISH) and immunohistochemistry in tissue microarray sections, respectively. ResultsAmong 114 patients, 99 (86.8%) had squamous cell carcinoma histologic features. EGFR gene amplification and high polysomy (EGFR FISH+) were observed in 7.9% and 31.6% of cases, respectively. Patients with EGFR FISH+ had significantly shorter overall survival (P = .011). A multivariate model confirmed that patients with EGFR FISH+ had a significantly greater risk of death than EGFR FISH− patients after adjusting for pathologic stage, presence of pleural invasion, venous invasion, and surgical margins (hazard ratio, 1.36; 95% CI, 1.040 to 1.782; P = .025). EGFR protein expression by immunohistochemistry was not associated with overall survival in the same group. Neither EGFR gene amplification nor EGFR immunohistochemistry expression was associated with relapse-free survival. ConclusionAn increased EGFR gene copy number in surgically resected NA-NSCLC was associated with worse survival.

Factors that Predict Clinical Benefit of EGFR TKI Therapy in Patients with EGFR Wild-Type Lung Adenocarcinoma.

BackgroundEpidermal growth factor receptor (EGFR) mutations in non-small cell lung cancers have emerged as key predictive biomarkers in EGFR tyrosine kinase inhibitor (TKI) treatment. However, a few patients with wild-type EGFR also respond to EGFR TKIs. This study investigated the factors predicting successful EGFR TKI treatment in lung adenocarcinoma patients with wild-type EGFR.MethodsWe examined 66 patients diagnosed with lung adenocarcinoma carrying wide-type EGFR who were treated with EGFR TKIs. The EGFR gene copy number was assessed by silver in situ hybridization (SISH). We evaluated the clinical factors and EGFR gene copy numbers that are associated with a favorable clinical response to EGFR TKIs.ResultsThe objective response rate was 12.1%, while the disease control rate was 40.9%. EGFR SISH analysis was feasible in 23 cases. Twelve patients tested EGFR SISH-positive, and 11 were EGFR SISH-negative, with no significant difference in tumor response and survival between EGFR SISH-positive and -negative patients. The overall median progression-free survival (PFS) and overall survival (OS) of 66 patients were 2.1 months and 9.7 months, respectively. Female sex and Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0–1 were independent predictors of PFS. ECOG PS 0–1 and a low tumor burden of extrathoracic metastasis were independent predictors of good OS.ConclusionFactors such as good PS, female sex, and low tumor burden may predict favorable outcomes following EGFR TKI therapy in patients with EGFR wild-type lung adenocarcinoma. However, EGFR gene copy number was not predictive of survival.

Epidermal growth factor receptor intron-1 CA repeat polymorphism on protein expression and clinical outcome in Taiwanese oral squamous cell carcinoma

This study was designed to explore the relationship between epidermal growth factor receptor (EGFR) CA repeats polymorphism and protein expression in oral cavity squamous cell carcinoma (OSCC). A total of 194 OSCCs were examined for EGFR protein overexpression, gene copy number and the length of their CA repeats. The length of the EGFR CA repeats was found not to be associated with EGFR gene copy number or with protein overexpression. To exclude the effect of EGFR gene copy number on protein overexpression, only those OSCC tumors with disomy of the EGFR gene were included in further analysis. In this subgroup, EGFR protein overexpression was significantly associated with poor differentiation of the tumor cells and lymph node metastasis, especially extra-capsular spread. However, EGFR CA repeats were not related to any clinicopathological factor. Interestingly, patients genetically found to have the EGFR CA repeats SS genotype and having tumors with EGFR protein overexpression were found to have a worst prognosis in terms of disease-free survival (DFS) (HR = 2.68; 95% CI, 1.03–6.98) after multivariate adjustment. The present study demonstrates that concurrent overexpression of EGFR protein in the presence genetically of the SS form CA repeats acts as a predictor for poor DFS.

Gefitinib and EGFR Gene Copy Number Aberrations in Esophageal Cancer.

Purpose The Cancer Esophagus Gefitinib trial demonstrated improved progression-free survival with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib relative to placebo in patients with advanced esophageal cancer who had disease progression after chemotherapy. Rapid and durable responses were observed in a minority of patients. We hypothesized that genetic aberration of the EGFR pathway would identify patients benefitting from gefitinib. Methods A prespecified, blinded molecular analysis of Cancer Esophagus Gefitinib trial tumors was conducted to compare efficacy of gefitinib with that of placebo according to EGFR copy number gain (CNG) and EGFR, KRAS, BRAF, and PIK3CA mutation status. EGFR CNG was determined by fluorescent in situ hybridization (FISH) using prespecified criteria and EGFR FISH-positive status was defined as high polysomy or amplification. Results Biomarker data were available for 340 patients. In EGFR FISH-positive tumors (20.2%), overall survival was improved with gefitinib compared with placebo (hazard ratio [HR] for death, 0.59; 95% CI, 0.35 to 1.00; P = .05). In EGFR FISH-negative tumors, there was no difference in overall survival with gefitinib compared with placebo (HR for death, 0.90; 95% CI, 0.69 to 1.18; P = .46). Patients with EGFR amplification (7.2%) gained greatest benefit from gefitinib (HR for death, 0.21; 95% CI, 0.07 to 0.64; P = .006). There was no difference in overall survival for gefitinib versus placebo for patients with EGFR, KRAS, BRAF, and PIK3CA mutations, or for any mutation versus none. Conclusion EGFR CNG assessed by FISH appears to identify a subgroup of patients with esophageal cancer who may benefit from gefitinib as a second-line treatment. Results of this study suggest that anti-EGFR therapies should be investigated in prospective clinical trials in different settings in EGFR FISH-positive and, in particular, EGFR-amplified esophageal cancer.

Anti-tumor efficacy of theliatinib in esophageal cancer patient-derived xenografts models with epidermal growth factor receptor (EGFR) overexpression and gene amplification.

Targeted therapy is not yet approved for esophageal cancer (EC). In this study, we first evaluated EGFR gene and protein expression in 70 Chinese EC patient tumor samples collected during surgery. We then established 23 patient-derived EC xenograft (PDECX) models and assessed the efficacy of theliatinib, a potent and highly selective EGFR inhibitor currently in Phase I clinical study, in 9 PDECX models exhibiting various EGFR expression levels. Immunohistochemical analysis showed that 50 patient tumor samples (71.4%) had high EGFR expression. Quantitative PCR showed that eight tumors (11.6%) had EGFR gene copy number gain, and fluorescence in situ hybridization (FISH) revealed that four tumors had EGFR gene amplification. These results suggest that EGFR protein may be overexpressed in many EC tumors without gene amplification. Also detected were rare hot-spot mutations in EGFR and PIK3CA, whereas no mutations were found in K-Ras or B-Raf. Theliatinib exhibited strong antitumor activity in PDECX models with high EGFR expression, including remarkable tumor regression in two PDECX models with both EGFR gene amplification and protein overexpression. However, the efficacy of theliatinib was diminished in models with PI3KCA mutations or FGFR1 overexpression in addition to high EGFR expression. This study demonstrates that theliatinib could potentially benefit EC patients with high EGFR protein expression without mutations or aberrant activities of associated factors, such as PI3KCA or FGFR1.

OA23.01 Anti-EGFR Monoclonal Antibodies plus Chemotherapy in the First-Line Treatment of Advanced NSCLC: A Meta-Analysis

Monoclonal Antibodies (mAbs) against the Epidermal Growth Factor Receptor (EGFR) in association with platinum-based doublet chemotherapy have emerged as a potential first-line treatment option for advanced non-small cell lung cancer (NSCLC). This study was conducted to systematically review available data and evaluate the efficacy and toxicity of anti-EGFR mAbs plus chemotherapy vs chemotherapy alone for advanced NSCLC. We carried out a search on network databases and oncology conference abstracts for studies between 1990 and January 2016. Only prospective randomized clinical trials were included. Primary endpoints were overall survival (OS) and toxicity frequency. Secondary endpoints were progression-free survival (PFS) and overall response rate (ORR). Subgroup analysis was performed assessing histological subtypes, EGFR protein expression by immunohistochemistry (IHC), EGFR gene copy number by fluorescence in-situ hybridization (FISH), EGFR mutation status, and smoking status. Seven studies (2 with necitumumab and 5 with cetuximab) were included with 5,057 patients. Compared to chemotherapy alone, significant benefits were demonstrated by the addition of anti-EGFR mAb to chemotherapy in OS (HR 0.90; 95%CI 0.84-0.95), PFS (HR 0.93; 95%CI 0.87-0.98), and ORR (OR 1.27; 95%CI 1.06-1.51). In subgroup analyses, the association of anti-EGFR mAb was associated with improved OS among patients with squamous histology (HR 0.84; 95%CI 0.76-0.92), tumours with high EGFR expression by IHC (HR 0.83; 95%CI 0.70-0.98), and smokers (HR 0.87; 95%CI 0.79-0.96). Patients with squamous histology and high EGFR expression by IHC achieved the highest benefit with the association (HR 0.71; 95%CI 0.59-0.86). The OS with the association also seemed to be higher in EGFR FISH negative and in EGFR wild-type tumours, but without statistical significance. Chemotherapy plus anti-EGFR mAb caused more grade 3 or worse adverse events (OR 1.73; 95%CI 1.50-2.00), remarkedly these known to be associated with anti-EGFR therapy, such as acne-like rash (OR 34.13; 95%CI 16.40-71.00) and hypomagnesemia (OR 6.23; 95%CI 3.04-12.77). Anti-EGFR therapy plus platinum-based doublet chemotherapy as first-line treatment demonstrated significant efficacy benefits with acceptable toxicity for advanced NSCLC. This benefit is more expressive among squamous histology with high EGFR expression. EGFR protein expression by IHC seems to be a predictive marker for survival in the association group. Further research is needed to corroborate these findings.

Frequency of EGFR T790M mutation and multimutational profiles of rebiopsy samples from non-small cell lung cancer developing acquired resistance to EGFR tyrosine kinase inhibitors in Japanese patients.

BackgroundThe majority of non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation eventually develop resistance to EGFR tyrosine kinase inhibitors (TKIs). Minimal information exists regarding genetic alterations in rebiopsy samples from Asian NSCLC patients who develop acquired resistance to EGFR-TKIs.MethodsWe retrospectively reviewed the medical records of patients with NSCLC harboring EGFR mutations who had undergone rebiopsies after developing acquired resistance to EGFR-TKIs. We analyzed 27 practicable samples using a tumor genotyping panel to assess 23 hot-spot sites of genetic alterations in nine genes (EGFR, KRAS, BRAF, PIK3CA, NRAS, MEK1, AKT1, PTEN, and HER2), gene copy number of EGFR, MET, PIK3CA, FGFR1, and FGFR2, and ALK, ROS1, and RET fusions. Additionally, 34 samples were analyzed by commercially available EGFR mutation tests.ResultsSixty-one patients underwent rebiopsy. Twenty-seven samples were analyzed using our tumor genotyping panel, and 34 samples were analyzed for EGFR mutations only by commercial clinical laboratories. Twenty-one patients (34 %) had EGFR T790M mutation. Using our tumor genotyping panel, MET gene copy number gain was observed in two of 27 (7 %) samples. Twenty patients received continuous treatment with EGFR-TKIs even after disease progression, and 11 of these patients had T790M mutation in rebiopsy samples. In contrast, only 10 of 41 patients who finished EGFR-TKI treatment at disease progression had T790M mutation. The frequency of T790M mutation in patients who received continuous treatment with EGFR-TKIs after disease progression was significantly higher than that in patients who finished EGFR-TKI treatment at disease progression (55 % versus 24 %, p = 0.018).ConclusionsThe frequency of T790M mutation in this study was lower than that in previous reports examining western patients. These results suggest that continuous treatment with EGFR-TKI after disease progression may enhance the frequency of EGFR T790M mutation in rebiopsy samples.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2902-0) contains supplementary material, which is available to authorized users.

EGFR gene copy number as a predictive/biomarker for patients with non-small-cell lung cancer receiving tyrosine kinase inhibitor treatment: a systematic review and meta-analysis

Epidermal growth factor receptor (EGFR) gene copy number has been proposed as a candidate biomarker for predicting treatment response to EGFR tyrosine kinase inhibitors (EGFR-TKIs) in patients with advanced non-small-cell...