EGFR Mutation Rate Research Articles

Abstract 3573: VariED: an integrated database of variants and gene expression profiles for genetic diseases

Abstract It is now widely believed that low-frequency variants may play an important role in cancers. In addition, low-frequency variants are usually closely related to populations. To identify the disease-associated variants, several projects are now underway to build a reference of genetic variations from different populations. Furthermore, massive tools and databases are available to compare the dynamic gene expression among different organs and predict functional effects of genetic variants. These resources aid to identify genetic roots of cancers in populations easier. Despite the existence of population allele frequency information, gene expression databases and functional effects of protein mutations, a comprehensive platform providing an integrated annotation database in human genetic variants, is still lacking. In the study, we proposed a web-based database to determine potential variations in cancers with collected variant information from current common databases and integrated those data to provide comprehensive analyses. The web-site offers a function to upload a variant call format (VCF) files for variants annotation. Importantly, we integrated population allele frequency information from NHBI GO Exome Sequencing Project (ESP), 1000 Genomes Project and Tohoku Medical Megabank Project to help users figure out the correlation between disease and population. Additionally, we also collected gene expression profiles from The Human Protein Atlas, Expression Atlas and NCBI SRA in different organs of human, mouse, and zebrafish respectively to reflect the relationship between gene expression and genetic variations in a specific organ. Overall, the database aids to predict protein functions in mutations, analyze population allele frequency and gene expression information from provided variants of diseases. In the result, we use three EGFR mutations to display the proposed system. A recent study has reported that Asian patients with non-small cell lung cancer (NSCLC) carrying a higher rate of EGFR mutations than non-Asian patients. These mutations, such as chr7:55241708G>C (G719A), chr7:55249005G>T (S768I) and chr7:55259515T>G (L858R), are found approximately in 30% of Asian (Japanese) patients. In functional prediction results, these sites are exonic and nonsynonymous mutations. The REVEL scores of three EGFR mutations are 0.824, 0.765 and 0.961, and gerp++ scores are 5.5, 5.85 and 5.71, respectively. Both REVEL and gerp++ show high scores for severe damage of protein structure in the mutations. According to the results, researchers can infer that the three mutations are pathogenic variants implying the nucleotide positions with a higher constraint. Citation Format: Li Mei Chiang, Chien Yueh Lee, Liang Chuan Lai, Mong Hsun Tsai, Tzu Pin Lu, Eric Y. Chuang. VariED: an integrated database of variants and gene expression profiles for genetic diseases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3573. doi:10.1158/1538-7445.AM2017-3573

Abstract 2773: A prospective observational study evaluating c-MET expression and EGFR gene mutation correlation with erlotinib response in second line treatment for advanced/metastatic non-small cell lung cancer patients

Abstract Background: The c-MET is associated with tumor progression and acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). The aim of this study was to evaluate the prevalence and predictive role of c-MET and EGFR mutation in non-small cell lung cancer (NSCLC). Methods: This was a multicenter prospective observational study for patients with stage IV or recurrent NSCLC who had progressive disease after 1st line chemotherapy and was followed by erlotinib for 2nd line treatment from September 2011 to September 2014. The primary outcome was to measure the rates of c-MET expression/amplification and EGFR mutation in tumor tissue. MET expression was evaluated by immunohistochemistry (IHC) and gene copy number was assessed by silver in situ hybridization (SISH). EGFR mutations were analyzed by Cobas™ version 1. Results: A total of 196 patients were enrolled and major histologic types were adenocarcinoma (67%). c-MET was overexpressed (MET IHC-positive) in 44.4% of the patients and dominant in female and non-squamous histology. c-MET amplification and high polysomy (MET SISH-positive) were observed in 1.5% and 8.7%, but there was no specific clinical characteristics. The detection rate of EGFR mutation was 10.2% (19 deletion: 11, L858R: 7, exon 20 insertion: 2 cases). The response rate of erlotinib was significantly higher in EGFR sensitive mutant group (55% vs. 4%, p<0.001) and the median progression-free survival (PFS) was significantly longer than wild type (173 vs 58 days, p<0.001). c-MET positivity (IHC- or SISH-positive) did not show significant correlation with response or PFS. Patients with SISH-positive for c-MET tended to have shorter overall survival (OS) than patients with SISH-negative (127 vs 303 days, p=0.051). Conclusion: In this observational study with 2nd line erlotinib treatment, we reconfirmed EGFR mutation is strong predictive marker, and EGFR-TKI use in EGFR wild-type patients should be considered carefully and may be harmful. c-MET overexpression was related to some clinical characteristics such as female and non-squamous histology. Although c-MET positivity was not associated with response or PFS, c-MET SISH may be predictive marker for OS. Citation Format: Cheol-Kyu Park, Yoo-Duk Choi, In-Jae Oh, Jung-Eun Lee, Shin Yup Lee, Tae-Won Jang, Jeong-Seon Ryu, Young-Chul Kim. A prospective observational study evaluating c-MET expression and EGFR gene mutation correlation with erlotinib response in second line treatment for advanced/metastatic non-small cell lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2773. doi:10.1158/1538-7445.AM2017-2773

Use of Oncogenic Driver Mutations in Staging of Multiple Primary Lung Carcinomas: A Single-Center Experience

ObjectiveThe staging of multiple pulmonary adenocarcinomas requires the distinction of intrapulmonary metastasis (IPM) from multiple primary lung cancers (MPLCs). This can be challenging in some patients, and the addition of data from oncogenic driver mutations in these tumors may be helpful in this determination. MethodsAs a proof of principle, molecular driver results from primary tumors and their metastases in 45 patients were compared (cohort 1). Then, 69 patients with a total of 154 synchronous or metachronous lung carcinomas were identified, and the pathologic findings were compared with oncogenic driver mutation. Each patient was assigned a highest potential T or M category on the basis of clinical, histopathologic, and molecular findings (cohort 2). ResultsThe concordance rate of EGFR, KRAS, BRAF, and ALK receptor tyrosine kinase gene (ALK) mutations was 96% in cohort 1. In cohort 2, 36% of multiple same-lobe nodules were MPLCs, 40% were IPM, and 24% were noninformative by molecular findings. Of nodules with multiple lobe involvement, 81.5% were MPLCs and 7.4% were IPM, with 11% noninformative. Of metachronous tumors, 52.9% were MPLCs. Overall survival was 100% at 2 years, 95% at 3 years, and 80% at 4 years in patients with available follow-up. ConclusionsOncogenic driver mutations are concordant between primary tumors and metastasis. The largest proportion of MPLCs was seen in tumors of multiple lobes, but with a substantial proportion of MPLCs among single-lobe nodules and with metachronous tumors. Overall survival was higher than expected for the respective highest T or M category, which is in support of the high frequency of MPLC.

A sensitive QPCR assay for EGFR mutation in plasma samples of NSCLC patients.

2595 Background: Tyrosine kinase inhibitors (TKI) have improved the overall outlook and quality of life for most of EGFR mutation positive NSCLC patients. However, tumor tissues are often absent or insufficient for testing EGFR mutations to guide EGFR TKIs treatment of patients with nonsmall cell lung cancer (NSCLC). An assay that detects EGFR mutations in the plasma would provide a noninvasive technique to assess suitability for TK inhibitor therapy. The ACCB new EGFR Mutation Kit is a ARMS-PCR test for the qualitative detection of 45 mutations in exons 18, 19, 20, and 21 of the EGFR gene in DNA derived from human plasma from NSCLC patients. Methods: 10 mL tubes of blood were collected from patients who never had been treated by EGFR TKI, and plasma circulating tumor DNA were extracted from plasma by Biomark Circulating DNA Kit. Qubit 2.0 Fluorometer was used to make plasma circulating DNA tumor quantitation. The concentration of final DNA sample is ≦2ng/μl. Total, 272 plasma DNA samples from 246 lung adenocarcinoma, 23 lung squamous carcinoma and 3 lung adenosquamous carcinoma patients were collected. 104 paired tissue EGFR mutations were detected by the same kit. Results: EGFR mutation was detected in 88 from 272 plasma DNA samples, 86 lung adenocarcinoma, 1 lung squamous carcinoma, 1 lung adenosquamous carcinoma, with EGFR mutation rate were 35.0% (86/246), 4.3% (1/23), 33.3% (1/3) respectively. In 61 Ⅰ~Ⅲ and 211 Ⅳ stage NSCLC patients, EGFR mutation rate were 21.3% (13/61) and 35.5% (75/211) respectively. Conclusions: The ACCB new EGFR Mutation Kit is a sensitive, accurate, rapid, and reproducible assay capable of testing DNA extracted from human plasma from NSCLC patients.

Impact on OS of 2nd and 3rd generation TKI in EGFR mt+ and ALK+ patients: Results of the NOWEL network.

e20560 Background: Available clinical research data shows that early mutation testing for patients with NSCLC stage IV could lead to an effective choice of therapy for patients with proven mutations. Targeted therapies achieve a higher ORR, PFS, OS and a better quality of life than chemotherapy in mt+ patients. With the advent of 2nd and 3rd generation TKI´s effective in 1st generation TKI resistant tumors, we wanted to study the impact of these drugs on the outcome of patients in a real life setting in 3 lung cancer centers. Methods: 1383 patients from the three cancer centers diagnosed with NSCLC stage IV (UICC 7) were examined. Methods for the detection of mutations included Sanger Sequencing, hybridization based COBAS testing as well as hybrid cage next generation sequencing. Results: 880/1383 (64%) consecutive patients with non-squamous cell NSCLC from the cancer centers were studied for the presence of tumor mutations, especially for EGFR and ALK mutations. The EGFR mutation rate was 16.6% (141/880), and the ALK-translocation rate 3.8% (24/635). Median OS in EGFR mt+ patients was 31 (n = 78) vs. 32 (n = 38) vs. 16 (n = 14) months respectively (center 1 vs. center 2 vs. center 3). Median OS in ALK mt+ patients was 25 (n = 17) months in center 1 and 11 (n = 5) months in center 2 (p < 0.05). Use of 3rd generation TKI Osimertinib (n = 17) lead to a significantly higher OS (n = 17, median OS 67 mo) than the use of only 1st and 2nd generation TKI (n = 113, median OS 24 mo, p < 0.000). Similarly, use of 2nd and 3rd generation ALKi impacted significantly on median OS: Crizotinib alone n = 7, 17 months, Crizotinib followed by Ceritinib and/or Brigatinib (n = 9) median OS not reached, p < 0.001. Conclusions: Smalldifferences in OS were observed, depending on the treatment centers, but the use of multiple EGFR and ALK-I impacted highly significantly on the outcome of patients with EGFR and ALK-alterations in a real life setting.

Alterations in the Β-catenin pathway in non-small cell lung cancer to define a distinct molecular subtype with prognostic and therapeutic implications.

11584 Background: The treatment of non-small cell lung cancer (NSCLC) has been revolutionized by the development of targeted therapy for distinct molecular subsets. Activation of the β-catenin pathway is essential for colorectal carcinoma tumorigenesis and has been implicated in hepatocellular, thyroid and ovarian cancer. The β-catenin pathway is involved in the cell adhesion complex and Wnt signaling. While mutations in this pathway have been reported in NSCLC and β-catenin overexpression correlates with worse survival, its role in lung tumorigenesis is poorly understood. Methods: We performed targeted next generation sequencing using the Ion Torrent Hotspot Cancer Panel v.2 on tumor tissue from 244 NSCLC patients in which we have defined key demographic and clinical parameters including stage and survival. This cohort contained 91 Stage I cases with mRNA expression data using an Illumina platform. Co-occurrence of genes in the β-catenin pathway and 27 other genes in the panel were assessed by Fisher’s exact test, with Benjamini-Hochberg adjustment for multiple comparisons. Results: Seventeen of 244 tumors had mutations in the β-catenin pathway (APC, CTNNB1, and NOTCH1): 10/170 non-squamous NSCLC (6%, 95% CI 3%-10%), and 7/70 squamous NSCLC (10%, 95% CI 5%-19%). The rate of EGFR and RB1 mutations was higher in tumors with b-catenin pathway mutation (5/17 and 2/17) than in those without (13/227 and 0/227, adjusted p = 0.06 for both). The presence of an APC mutation was also associated with higher mRNA expression of the pro-survival protein, BCL2 (n = 91; 5/41 vs. 0/50, unadjusted p = 0.022, adjusted p = 0.3). Furthermore, APC mutations were more frequently observed in tumors with higher levels of EMT markers (high VIM 8% vs. low VIM 0%, unadjusted p = 0.16) and EMT transcription factors (10% vs. low expression 2%, unadjusted p = 0.16). Finally, we observed a trend toward worse overall survival in non-squamous tumors with mutations in the β-catenin pathway (n = 170, log rank test p = 0.07). Conclusions: These studies suggest that tumors with b-catenin pathway alterations are defined by a more mesenchymal and potentially drug resistant subtype which portends a poor prognosis.

Characterization of common and rare mutations in EGFR and associated clinicopathological features in a large population of Chinese patients with lung cancer

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.

Precision medical treatment of non-adenocarcinoma NSCLC patients with EGFR mutation

EGFR tyrosine kinase inhibitors (TKIs) treatment has been established as standard therapy for EGFR-mutated adenocarcinomas. In the studies which published prospective randomized trials comparing EGFR TKIs with chemotherapy, a very low percentage of EGFR-mutated non-adenocarcinomas was enrolled in clinical trials. The efficacy of TKIs treatment for EGFR-mutated non-adenocarcinomas and their relationship with clinicopathological characteristics remain debatable. The results of retrospective studies show that the frequency of EGFR mutation is lower in non-adenocarcinoma than that of adenocarcinoma and efficacy of TKIs treatment for non-adenocarcinoma is inferior to adenocarcinoma. Smoking status is significantly associated with the efficacy of TKIs treatment for EGFR-mutated non-adenocarcinomas. The EGFR mutation rate and efficacy of TKIs treatment in adenosquamous cell carcinoma are higher than those of squamous cell carcinoma or large cell lung carcinoma. It may be concluded that the incidence of EGFR mutations in patients with non-adenocarcinoma NSCLC from mainland China is not very low and it is reasonable that EGFR TKIs could be an option for the treatment of EGFR-mutated non-adenocarcinoma NSCLC, especially for patients with adenosquamous histology and non-smokers. It is necessary to conduct a large-sample prospective study to understand the clinicopathological characteristics of non-adenocarcinomas and to evaluate the efficacy of EGFR TKI treatment or/and chemotherapy for EGFR-mutated non-adenocarcinoma NSCLC.

P1.02-049 EGFR, KRAS and ALK Gene Alterations in Lung Cancer Patients in Croatia

Rates in targetable gene changes varies between different populations of lung cancer patients. Targetable gene changes include changes in EGFR and ALK gene, as well as KRAS gene. Primary aim of this study was to determine mutation status in purely Caucasian Croatian population. Rates in targetable gene changes varies between different populations of lung cancer patients. Targetable gene changes include changes in EGFR and ALK gene, as well as KRAS gene. Primary aim of this study was to determine mutation status in purely Caucasian Croatian population. During 6 months period 324 newly diagnosed primary lung adenocarcinoma were tested. Out of 324 tested patients, 194 were males (60%) and 130 females (40%) mean age 64 years (range 35 to 88 years). Vast majority of patients were in stages 3 and 4 (more than 80%). Among males, 87% of patients were ever smokers, and among females 61% of patients were ever smokers. Significantly higher rates of ever smokers were recorded among males. EGFR mutations were present in 15.7% of patients (51 patients). There was a difference in EGFR mutation rates between males and females (5.6 vs 30.8%, p<0.0001). KRAS mutations (codones 12/12 and 61) were present in 35.8% (116) patients, and ALK translocation detected by IHC in 3.7% (12) patients. Molecular testing in primary lung adenocarcinoma patients was done in purely Caucasian Croatian population. EGFR mutation and ALK translocation rates were similar to previously published data. However, KRAS mutation rates were higher than previously published. This can be associated with high smoking rates in Croatian population.

Prevalence of EGFR and ALK Mutations in Lung Adenocarcinomas in the Levant Area - a Prospective Analysis

Background:A significant percentage of lung adenocarcinomas have a driver mutation. To date, there has been no assessment of the prevalence of such mutations in a Middle Eastern population. The present multicenter prospective study of formalin fixed paraffin embedded (FFPE) tissues from patients diagnosed with lung adenocarcinoma was performed to assess the prevalence of EGFR and ALK mutations in the Levant.Methods:Patients of Middle Eastern origin with lung adenocarcinomas at 10 sites in Lebanon, Jordan and Iraq were prospectively enrolled. Tumors were tested for EGFR by PCR and for EML4-ALK translocation by fluorescence in situ hybridization (FISH).Results:A total of 210 patients were enrolled, 139 (66.2%) males and 71 females (33.8%), with a mean age of 63.4 years. EGFR testing of 205 (97.6%) demonstrated the wild type in 173 (84.4%) and mutated forms in 32 (15.6%). Some 46.9% of EGFR positive patients were non-smokers and 62.5% were females as opposed to 22.4% and 33.8%, respectively, in the general population. As for the EML4-ALK translocation, testing in 157 (74.8%) cases gave negative results in 154 (98.1%), only 3 being positive (1.9%), 2 being females and 2 non-smokers.Conclusion:Our study established a 15.6% EGFR mutation rate in lung adenocarcinomas with ALK translocation mutations in only 1.9%, as compared to a 15-20% and 5%, respectively, in the Western literature.

P1.02-042 Detection of ALK Protein Expression in Lung Adenocarcinomas, a Consecutive Series of Cases from Northeastern Brazil

There have been very few studies on ALK status in lung adenocarcinomas in Latin American population. No prior reports in Northeastern Brazil have been published. We analyzed ALK protein expression with a specific antibody (D5F3 clone) with the Ventana system in a series of consecutive cases from Northeastern Brazil, a previously untested population, and correlated with histologic subtypes according to the 2015 WHO Classification. A total of 94 patients (55% female, mean age 62 years) were tested, including 51 solid, 29 acinar, 6 lepidic, 6 papillary predominant and 2 sarcomatoid carcinomas with adenocarcinoma components. There were 9 positive cases (9.5%), 5 solid predominant, 3 acinar predominant and 1 lepidic. One of the 3 acinar cases had a mucinous component. The positive cases were more often male (p<0.05) with no significant differences in relation to age, smoking history or histologic subtype. The negative cases showed a 32% EGFR mutation rate. Follow-up will be presented. We will describe a series of consecutive adenocarciomas from a population with unknown ALK status with a higher than expected rates, and correlate with the 2015 WHO Classification of Tumors.

P3.02b-054 EGFR Mutation Profile in Newly Diagnosed Lung Adenocarcinoma in Persahabatan Hospital, Jakarta-Indonesia

In Indonesia, gefitinib or erlotinib were given for free under National Health System Insurance, for EGFR sensitizing mutaton positive patients. Our previous study showed proportion of common EGFR mutation in Indonesian patients, however, the proportion of uncommon mutation and resistant mutation were not yet known. Here we report the spectrum of EGFR mutation among newly diagnosed-therapy naive adenocarcinoma NSCLC in respiratory referral hospital, Persahabatan Hospital, Jakarta Indonesia. Newly diagnosed-therapy naive lung adenocarcinoma were evaluated for EGFR mutation between September 2015–April 2016. Four exons of EGFR were tested using a combination of PCR High Resolution Melting, fragment sizing, and direct DNA sequencing. One hundred and thirty nine subjects were enrolled from September 2015 to March 2016 in Persahabatan hospital, with distribution 63% were male, and 56 years old (mean). Most specimens were obtained using bronchoscopy (31%) followed by TTNA (30%) and pleural effusion (17%). Overall EGFR mutation rate was 61.9%, and more frequent in female (72% of female subjects has EGFR mutation whereas only 55% of male subjects has positive results). Of the positive EGFR mutation subjects; 1% has Exon 18 G17S; 5.8 % Exon 18 G719S; 17.5% Exon 19 In/Del; 43% Exon 21 L858R; and 21% Exon 21 L861Q. The incidence of primary resistant Exon 20 T790M mutation was 11.6% and more frequent in female. EGFR mutation is common in Indonesian population of newly diagnosed naive adecarcinoma NSCLC. Baseline rate of T790M was not rare when detected using standard direct DNA sequencing. Further study is needed to elaborate proportion of primary resistant and biological mechanism in Indonesian lung cancer patients.

PUB079 EGFR and BRAF Mutation Detection in FFPE Samples of Lung Adenocarcinoma

EGFR-TKIs have been the standard first-line treatment for metastatic NSCLC patients with sensitive EGFR-mutants, meanwhile, other drugs target different driver mutants like BRAF-inhibitor dabrafenib has shown promising efficacy for metastatic BRAF-mutated NSCLC patients. Therefore, spotting patients carrying the targeted mutations is of great significance. However, molecular detection methods applied in clinical practice, especially detection of BRAF in NSCLC patients needs further exploration. Therefore, more sensitive and economic methods are required. We applied the CastPCR technology to the molecular detection of EGFR (del2235-2249, del2236-2250, T790M, L858R) and BRAF (V600E, G469A, D594G) mutations in 144 treatment-naive adenocarcinomas of the lung, and analyzed the association between the mutation rates and patients' clinicopathological features. EGFR mutation: 74 (51.4%, 74/144) cases were identified harboring EGFR mutations. 58 (40.3%, 58/144) carried sensitizing mutations (19Del or L858R) and 21 (14.6%, 21/144) carried resistant mutations (T790M). 10 (6.9%, 10/144) mutation-positive patients were double-mutated. EGFR mutation rate was significantly higher in female compared with that of males (60.9% v.s. 43.8%, P＜0.05), in non-smokers compared with that of smokers (62.8% v.s. 34.5%, P＜0.05). BRAF mutation:12 (8.3%, 12/144) patients were identified with BRAF mutations. 2 were V600E (16.7%, 2/12) and 10 (83.3%, 10/12) were non-V600E. Among the 10 non-V600E mutations, D594G accounted for 9 (90.0%，9/10) and G469A accounted for only 1 (10.0%, 1/10). Statistical analysis demonstrated that BRAF mutation rate was not associated with any of the clinicopathological features: age, gender, smoking status, differentiation degree, tumor size, regional lymph nodes metastasis and distant metastasis of (P≥0.05). The CastPCR technology is a robust method with high sensitivity for molecular detecting of EGFR and BRAF mutations in clinical FFPE samples.

1582P - Analysis of circulating cell-free DNA in plasma shows a higher detection rate of EGFR mutations in patients with extrathoracic disease progression

1582P - Analysis of circulating cell-free DNA in plasma shows a higher detection rate of EGFR mutations in patients with extrathoracic disease progression

Prevalence of Tissue EGFR Mutation in Patients of Adenocarcinoma Lung and Its Ability to Predict Response to Tyrosine Kinase Inhibitors

SESSION TITLE: Lung Cancer III SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, October 26, 2016 at 01:30 PM - 02:30 PM PURPOSE: To estimate the prevalence of tissue EGFR mutation in patients of adenocarcinoma lung and its predictive value on treatment response to TKIs METHODS: Treatment naive patients of adenocarcinoma lung were recruited. Al patients underwent complete staging and tissue EGFR mutation analysis using DNA extraction and Polymerase chain reaction. Patients were treated with Gefitinib if they were EGFR positive and platinum based doublet chemotherapy if they were EGFR negative. Treatment response was evaluated after 3 months of Gefitinib / 4 cycles of chemotherapy by using CT-PET scan. Prevalence tissue EGFR was estimated and response correlation to EGFR mutation was done using student t-test RESULTS: 102 patients were enrolled (61 % males, mean age of 56.2 (SD 10.2) years. 39 % were never smokers, 31% were current smokers and 30 % were reformed smokers. Tissue EGFR mutation was seen in 21 patients (20.6%), exon 18 mutation in 1 patient, exon 19 in 14 patients, exon 20 in 1 patient and exon 21 in 5 patients. 58 patients completed response evaluation at 3 months/ 4 cycles. Of these 17 were EGFR positive and 41 were EGFR negative. The response rates in both arms were: complete response 6% vs 0 %, partial response 41 % vs 27%, stable disease 12% vs 22%, progressive disease 18% vs 17%, and death rate 23% vs 34%. Disease control rate was 47 % in EGFR positive patients 27% in EGFR negative patients (p=0.18). Overall response rate was 59 % in EGFR positive patients vs 49% in EGFR negative patients (p = 0.48). CONCLUSIONS: Tissue EGFR mutation rate was 20.6%. Patients who are Tissue EGFR mutation positive show better response if treated with TKIs than patients who are EGFR negative and receive conventional chemotherapy although the difference is not statistically significant probably due to a small sample size. CLINICAL IMPLICATIONS: EGFR positivity in Non small cell Lung Cancer offers better prospects of clinical response if patients are treated with TKIs. DISCLOSURE: The following authors have nothing to disclose: Ashutosh Dhanuka, Anant Mohan, Randeep Guleria, Gopi Khilnani, Karan Madan, Vijay Hadda, Alpana Saxena No Product/Research Disclosure Information

Clinicopathological, Immunohistochemical, and Genetic Features of Primary Lung Adenocarcinoma Occurring in the Setting of Usual Interstitial Pneumonia Pattern

IntroductionAn association between usual interstitial pneumonia (UIP) and carcinogenesis has been well established. However, few detailed analyses have investigated the clinicopathological, immunohistochemical, and genetic features of patients with primary lung adenocarcinoma (ADC) with UIP (UIP-ADC). MethodsWe identified 44 patients with ADC in the setting of UIP (the UIP-ADC group) (1.9%) from 2309 patients with primary ADC and compared clinicopathological, immunohistochemical, and genetic features between the UIP-ADC group and patients with ADC without UIP (the non–UIP-ADC group). ResultsClinicopathological features of UIP-ADC included an older age at occurrence; male predominance; smoking history; predilection for the lower lobe; large tumor size; high incidence of lymph vessel invasion, pleural invasion, and lymph node metastasis; and poor survival rate. However, the cause of death of patients with UIP-ADC was largely influenced by respiratory complications. Histologically, patients in the UIP-ADC group could be stratified according to invasive mucinous-predominant subtype. Genetically, patients in the UIP-ADC group had lower EGFR and higher KRAS mutation rates compared with patients in the non–UIP-ADC group. ConclusionsUIP-ADC was associated with a poor prognosis owing to the high frequency of perioperative complications rather than the malignancy of the tumor itself. There was a high prevalence of the invasive mucinous-predominant subtype in cases of UIP-ADC. UIP-ADC also had a low prevalence of EGFR mutations and a high prevalence of KRAS mutations. These findings suggest that UIP-ADC should be distinct from non–UIP-ADC.

Gene expression of MAGE-A3 and PRAME tumor antigens and EGFR mutational status in Taiwanese non-small cell lung cancer patients.

To determine the frequency of expression of the tumor-associated antigens (TAAs) melanoma-associated antigen A3 (MAGE-A3) and preferentially expressed antigen of melanoma (PRAME) and the rate of EGFR mutations in a Taiwanese non-small cell lung cancer (NSCLC) population including only adenocarcinomas and squamous cell carcinomas. Furthermore, to investigate associations between TAA expression and EGFR mutations and to evaluate these TAAs as prognostic markers for overall survival. The occurrence of single nucleotide polymorphisms in MAGEA3 and PRAME was also assessed. Archival fresh-frozen tumor tissue specimens were tested by quantitative reverse transcription polymerase chain reaction assays to detect MAGE-A3 and PRAME expression. EGFR mutations were detected by mass spectroscopy and single nucleotide polymorphisms by gene sequencing. Of the 156 adenocarcinomas examined, 3.3% expressed MAGE-A3, 32.2% expressed PRAME and 62.8% had EGFR mutations. Of the 128 squamous cell carcinomas, 29.8% expressed MAGE-A3, 59.2% expressed PRAME and 20.5% harbored EGFR mutations. TAA expression was similar across subgroups determined by patient or tumor characteristics. There was no association between TAA expression and EGFR mutation status and TAA expression was found not to be a prognostic marker for survival. Single nucleotide polymorphisms were identified, one of which with a possible impact on MAGE-A3 expression. In this NSCLC population, expression of MAGE-A3 and PRAME was more frequent in squamous cell carcinomas than in adenocarcinomas tumors. EGFR mutations were not associated with TAA expression for either histology and were three times more frequent in adenocarcinomas than in squamous cell carcinomas tumors.

Epidermal growth factor receptor mutations in adenocarcinoma in situ and minimally invasive adenocarcinoma detected using mutation-specific monoclonal antibodies

ObjectivesEpidermal growth factor receptor (EGFR) mutation rates in adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) were studied using both DNA analysis and mutation-specific immunohistochemistry. Materials and methodsThe peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp method was used to detect mutations in exons 18, 19, 20, and 21 of the EGFR gene in DNA samples extracted from paraffin-embedded tissue sections. Simultaneously, immunohistochemical analysis with two EGFR mutation-specific monoclonal antibodies was used to identify proteins resulting from an in-frame deletion in exon 19 (E746_A750del) and a point mutation replacing leucine with arginine at codon 858 of exon 21 (L858R). ResultsForty-three tumors (22 AIS and 21 MIA) were examined. The EGFR mutation rate in AIS detected by DNA analysis was 27.3% (L858R, 5/22; exon 19 deletion,1/22), whereas that detected in MIA was 42.9% (L858R,4/21; exon 19 deletion,5/21). Mutations detected by immunohistochemical analysis included 22.7% (L858R, 4/22; exon 19 deletion, 1/22) in AIS and 42.9% (L858R, 4/21; exon 19 deletion, 5/21) in MIA. Although some results were contradictory, concordant results were obtained using both assays in 38 of 43 cases (88.4%). ConclusionDNA and immunohistochemical analyses revealed similar EGFR mutation rates in both MIA and AIS, suggesting that mutation-specific monoclonal antibodies are useful to confirm DNA assay results.

A single institution experience of EGFR inhibitors in patients with advanced squamous cell anal carcinomas (SCAC).

623 Background: Although SCAC are relatively rare, their incidence has been increasing steadily. Because of limited data, treatment of metastatic disease is a major therapeutic challenge. Recent data has demonstrated a low rate of KRAS and EGFR mutations, suggesting a potential target of EGFR inhibitors. In this study, we report the safety and efficacy of EGFR inhibitors in patients (pts) with advanced SCAC. Methods: A retrospective analysis was conducted using the Moffitt Cancer tumor registry from 1/2009 to 1/2014. Eligible pts had advanced SCAC and received an EGFR inhibitor as part of their treatment. Results: 13 pts were identified for analysis. Median age was 59 years (range: 41-68). All pts received concurrent chemoradiation (Nigro regimen) as initial treatment and subsequently had recurrence. Upon diagnosis of recurrent disease, 5 pts received 2 lines of systemic chemotherapy, 5 pts received 1 line and 3 did not receive any treatment prior to receiving EGFR inhibitors. 5 pts received single agent cetuximab (4) or panitumumab (1) and the others received cetuximab or panitumumab with irinotecan or FOLFIRI. Pts received a median EGFR inhibitor dose of 8 (range: 2-45). Objective response rates were 30.8% (1 CR, 3 PR) and disease control rates were 46.2%. 1 pt with CR was on single agent cetuximab as second line therapy and 3 pts with PR were on cetuximab plus chemotherapy as front-line. With a median follow-up of 9.6 months (mo), the median PFS and median OS were 4.4 mo (95% confidence interval (CI) 2.99-5.81) and 11.4 mo (95% CI 7.93-14.87), respectively. No KRAS mutation was detected in 8 pts and KRAS testing was not done on 5 other pts. Grade 3 toxicities included anemia (n = 2), fatigue (n = 1), depression (n = 1), dyspnea (n = 1), anorexia (n = 1), nausea (n = 1) and diarrhea (n = 1). No grade 4 toxicities were observed. Conclusions: Our analysis suggests that EFGF inhibitors have potential efficacy and are reasonably well tolerated in patients with SCAC. These findings warrant further evaluation in a large prospective trial.

Detection of EGFR and KRAS Mutation by Pyrosequencing Analysis in Cytologic Samples of Non-Small Cell Lung Cancer.

EGFR and KRAS mutations are two of the most common mutations that are present in lung cancer. Screening and detecting these mutations are of issue these days, and many different methods and tissue samples are currently used to effectively detect these two mutations. In this study, we aimed to evaluate the testing for EGFR and KRAS mutations by pyrosequencing method, and compared the yield of cytology versus histology specimens in a consecutive series of patients with lung cancer. We retrospectively reviewed EGFR and KRAS mutation results of 399 (patients with EGFR mutation test) and 323 patients (patients with KRAS mutation test) diagnosed with lung cancer in Konkuk University Medical Center from 2008 to 2014. Among them, 60 patients had received both EGFR and KRAS mutation studies. We compared the detection rate of EGFR and KRAS tests in cytology, biopsy, and resection specimens. EGFR and KRAS mutations were detected in 29.8% and 8.7% of total patients, and the positive mutation results of EGFR and KRAS were mutually exclusive. The detection rate of EGFR mutation in cytology was higher than non-cytology (biopsy or resection) materials (cytology: 48.5%, non-cytology: 26.1%), and the detection rate of KRAS mutation in cytology specimens was comparable to non-cytology specimens (cytology: 8.3%, non-cytology: 8.7%). We suggest that cytology specimens are good alternatives that can readily substitute tissue samples for testing both EGFR and KRAS mutations. Moreover, pyrosequencing method is highly sensitive in detecting EGFR and KRAS mutations in lung cancer patients.