Growth Factor Receptor Gene Mutations Research Articles

Implementation of modern therapy approaches and research for non-small cell lung cancer in Japan.

The genetic backgrounds of the Japanese (or Asians) are, at least in part, different from those of Caucasians. It is necessary to recognize this difference to develop medicine that is both optimized and individualized. In particular, the consideration of ethnic differences is becoming increasingly important for lung cancer medicine. Japanese clinical practice guidelines indicate that some clinical biomarkers, such as epidermal growth factor receptor gene mutations, echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase fusion gene and uridine diphosphate glucuronosyltransferase genotypes should be determined in appropriate lung cancer patients. At the present time, tests for these biomarkers are covered by the Japanese national health-care programme, as is treatment with certain targeted drugs and cytotoxic agents. Therefore, most patients with lung cancer in Japan receive these tests as part of daily practice if their performance status and organ function are judged to be eligible. In addition, ethnic differences in bone marrow toxicity caused by cytotoxic drugs are reflected in treatment choice, and the requirements for the development of treatment modalities suitable for rare targeted populations are also increasing. To meet these requirements, many collaborative groups in Japan that have improved their infrastructure for investigator-initiated trials and conducted important activities need to provide further optimal treatment modalities for Japanese and Asian patients with lung cancer. Here, the characteristics of lung cancer in Japanese patients, general aspects of medical treatment and the care system in Japan, and representative studies on lung cancer in Japan are reviewed.

Contribution of ultrasound-guided fine-needle aspiration cell blocks of metastatic supraclavicular lymph nodes to the diagnosis of lung cancer.

Routine smears of fine-needle aspiration (FNA) specimens of supraclavicular lymph nodes with ultrasound (US) real-time guidance have proven useful in lung cancer staging, but the clinical value of additional information from cell-block of FNA samples has been little researched. This study mainly focused on the contribution of cell block analysis to the diagnosis and staging in lung cancer. Clinical data about 211 lung cancer patients with supraclavicular lymph node enlargement admitted to ultrasonography in the Zhejiang Cancer Hospital and recommended a needle biopsy under US-guided, the adequacy of the specimens for preparing cell blocks was acquireded, and the additional immunohistochemistry or genetic information provided from cell block analysis was examined. In 211 lung cancer patients referred for US-guided FNA (median age 61.8 ± 10.0 years, range 30-88) 279 aspirations were performed. Conventional smears could be obtained from 185 aspirates (66.3%) and contained 176 (95.1%) diagnostic smears. Cell blocks could be obtained from 94 aspirates (33.7%) and contained diagnostic material in 88 (93.6%) aspirates. Above all, cell blocks also made epithelial growth factor receptor gene mutation analysis in 17 patients with FNA samples, and the positive rate was 70.6%. Overall, cell blocks provided clinically significant information for 51 of the 211 patients participating in the study (24.2%). Cell-block samples from US-guided FNA is a promising, relatively noninvasive technique to provide additional information in lung cancer diagnosis. Analysis of cell blocks allows for genetic analysis of the patients with supraclavicular lymph nodes metastasis.

Uterine metastasis of lung adenocarcinoma revealed by the same epidermal growth factor receptor mutation in both lung and endometrial biopsies

Abstract We experienced a rare case of uterine metastasis of non-small cell lung cancer in an 82-year-old Japanese woman revealed by detecting the same epidermal growth factor receptor (EGFR) gene mutation in both lung and endometrial biopsy specimens. The patient noticed abnormal genital bleeding at the first presentation. Further examination revealed huge masses in both lung and uterus. Biopsies from the lung and endometrium were performed. Although the pathological findings of both specimens showed similar adenocarcinomatous features including intracytoplasmic luminas, immunohistochemical analyses could not clarify whether these two tumors are lung metastasis of endometrial adenocarcinoma, uterine metastasis of lung adenocarcinoma or double primary adenocarcinomas of the lung and endometrium. Mutational analyses of EGFR gene using genomic DNA revealed that both lung and endometrial tumors had the same substitution mutation (L858R) at exon 21 which is often observed in lung adenocarcinomas. Since EGFR mutations are rarely detected in primary endometrial cancers and especially L858R mutation has not been reported in them, detection of the same L858R EGFR gene mutation in both lung and endometrial tumors strongly suggested that uterine tumor is the metastasis of lung adenocarcinoma. Mutational analyses might be useful to determine whether the tumor is primary or metastatic when the particular mutational types are observed in particular tumor types and/or particular organs.

Epidermal growth factor receptor mutations in East European non-small cell lung cancer patients.

Epidermal growth factor receptor (EGFR) gene mutations are recurrently observed in non-small cell lung carcinomas (NSCLCs), and it has been found that they may serve as specific therapeutic targets. The aim of the present study was to determine the prevalence of EGFR gene mutations in NSCLCs in an East European (Bulgarian) population in different histological subtypes, in cytological versus histological samples and in primary versus metastatic lesions. In this study 1427 NSCLC samples were included. DNA was extracted from either formalin-fixed paraffin embedded (FFPE) tissues or cytology specimens and analyzed for the presence of 29 recurrent EGFR gene mutations using SARMS PCR. EGFR gene mutations were found to occur significantly more often in female than in male patients (19.4% vs. 5.4%; p<0.001), in adenocarcinomas than in squamous cell carcinomas or other histological subtypes (12.5% vs. 6.2%, and 7.6%, respectively; p=0.009), and in never smokers than in ex-smokers and current smokers (22.9% vs. 8.5% and 4.9%, respectively; p<0.001). No significant differences were observed in the occurrence of EGFR gene mutations in primary tumors compared to metastases (7.9% vs. 11.2%; p=0.092), or in FFPE samples compared to cytological samples (8.9% vs. 8.1%; p=0.813). Our data show that the overall frequency of EGFR gene mutations in lung adenocarcinomas in the East European cohort studied is within the range of that observed in North American and West European populations, but that its frequency in squamous cell carcinomas is higher than that in any population reported to date. All specimens appeared to be suitable for EGFR gene mutation analysis, irrespective nature or origin.

MEK inhibitor for gastric cancer with MEK1 gene mutations.

The prognosis for patients with unresectable advanced or recurrent gastric cancer remains poor. The identification of additional oncogenes with influences similar to those of epidermal growth factor receptor gene mutations, upon which the growth of cancer cells is dependent, is needed. In this study, we evaluated sensitivity to MEK inhibitors (GSK1120212 and PD0325901) in several gastric cancer cell lines in vitro and found three poorly differentiated gastric cancer cell lines that were hypersensitive to the inhibitors. The sequence analyses in these three cell lines revealed that one cell line had a novel MEK1 mutation, while the other two had previously reported KRAS and MEK1 mutations, respectively; the gene statuses of the other resistant cell lines were all wild-type. Experiments using MEK1 expression vectors demonstrated that the MEK1 mutations induced the phosphorylation of ERK1/2 and had a transforming potential, enhancing the tumorigenicity. The MEK inhibitor dramatically reduced the phosphorylation of ERK1/2 and induced apoptosis in the cell lines with MEK1 mutations. In vivo, tumor growth was also dramatically decreased by an inhibitor. One of the 46 gastric cancer clinical samples that were examined had a MEK1 mutation; this tumor had a poorly differentiated histology. Considering the addiction of cancer cells to active MEK1 mutations for proliferation, gastric cancer with such oncogenic MEK1 mutations might be suitable for targeted therapy with MEK inhibitors.

Clinical usefulness of gefitinib for non-small-cell lung cancer with a double epidermal growth factor receptor mutation.

The aim of this study was to investigate whether the pattern of epidermal growth factor receptor (EGFR) gene mutations affects sensitivity to gefitinib treatment. We investigated 44 surgically resected non-small-cell lung cancer (NSCLC) specimens obtained between 2001 and 2012 at the Tokyo Medical University Hospital. The specimens were obtained from patients treated with gefitinib as 1st-, 2nd-, or 3rd-line therapy for postoperative recurrent NSCLC. We detected EGFR mutations using the cycleave PCR technique. In addition, the specimens from non-responders were stained with antibodies against hepatocyte growth factor receptor (HGFR; MET) and hepatocyte growth factor (HGF). We assessed the progression of non-responders over a period of 2 months. Intermediate responders were considered to be patients who responded (exhibiting at least stable disease) to gefitinib therapy for 3-11 months, while long-term responders were defined as those who responded to gefitinib therapy for >12 months. The NSCLCs were histologically classified as 43 adenocarcinomas and one large-cell neuroendocrine carcinoma. One patient had an exon 18 point mutation, 23 an exon 19 deletion, 2 an exon 20 point mutation, 16 an exon 21 point mutation and 2 patients had both exon 20 and 21 point mutations. There were 4 non-responders, including the 2 patients with exon 20 mutation, 25 intermediate responders (including 10 patients under ongoing treatment) and 15 long-term responders (2 of whom are under ongoing treatment), including the 2 patients with both exon 20 and 21 mutations. Of the specimens obtained from non-responders, 3 stained with the anti- MET antibody and 1 stained with the anti-HGF antibody. Therefore, NSCLC with exon 20 mutation may respond to gefitinib treatment in the presence of an additional EGFR mutation.

O10. Allele-specific real-time PCR detection of EGFR exon 19 and 21 mutations in various clinical non-small cell lung cancer specimens

Background The aim of our study was to evaluate the effectiveness of epidermal growth factor receptor (EGFR) gene mutation detection in diverse materials from 707 non-small cell lung cancer (NSCLC) patients using the two ultra-sensitive allele-specific real-time polymerase chain reaction (PCR) assays in the routine diagnostic procedure.

O2. Frequency of EGFR gene mutations in patients with NSCLC in Czech Republic

Background: Worldwide, lung cancer is the most common cause of cancer-related death, and was responsible for 1.56 million deaths annually, as of 2012. The situation in the Czech Republic is identical, lung cancer is the leading cause of mortality due to malignant tumours, with 5,572 cancer related deaths in 2010. The detection of epidermal growth factor receptor (EGFR) gene mutations can guide targeted therapies for non-small cell lung cancer (NSCLC), because most of these mutations are strongly associated with clinical response to EGFR tyrosine kinase inhibitors. The aim of this study was to verify the frequency of EGFR mutations in a large group of Caucasians patients with advanced stage non-squamous NSCLC. Methods: Analysed data were collected in the period from November 15, 2011 to June 30, 2013 in three pneumo-oncological centres. Totally, 486 patients diagnosed with adenocarcinoma (459 cases) or NSCLC-NOS (27 cases) were tested for EGFR mutations, consisting of 284 males and 202 females, with median age of 66.5 years. Results: EGFR mutations were detected in 74 patients (15.2%). Mutations were shown in 25 (8.8%) men vs. 49 (24.3%) women (P<0.001), in 12 (6.7%) smokers vs. 20 (11.2%) ex-smokers vs. 38 (37.3%) non-smokers (P<0.001), and in 32 (15.7%) patients under 65 years of age vs. 42 (14.9%) patients over 65 years of age (P=0.898). Conclusions: The authors showed that the overall frequency of EGFR mutations in patients with non-squamous NSCLC was 15.2%, most commonly in female patients and non-smokers. The study results are in concordance with recent studies in which the frequency of EGFR mutations varies between 8-23% in Caucasian population. This information can help us to estimate number of patients who will need EGFR tyrosine kinase inhibitors in the first line of treatment.

EGFR biomarkers predict benefit from vandetanib in combination with docetaxel in a randomized phase III study of second-line treatment of patients with advanced non-small cell lung cancer

ZODIAC was a randomized phase III study of second-line treatment in patients with advanced non-small cell lung cancer (NSCLC) that evaluated the addition of vandetanib to docetaxel. The study showed a statistically significant improvement in progression-free survival and objective response rate, but not in overall survival for unselected patients. This study evaluated epidermal growth factor receptor (EGFR) gene mutation, copy number gain, and protein expression, and KRAS gene mutation, in pretreatment tumor samples as potential biomarkers predicting benefit from vandetanib as second-line treatment of NSCLC. After progression following first-line chemotherapy, 1391 patients with locally advanced or metastatic (stage IIIB/IV) NSCLC were randomized 1 : 1 to receive vandetanib (100 mg/day) plus docetaxel (75 mg/m(2) every 21 days) or placebo plus docetaxel in the ZODIAC study. Archival tumor samples (n = 570) were collected from consenting patients (n = 958) for predefined, prospective biomarker analyses. Of evaluable samples, 14% were EGFR mutation positive, 35% were EGFR FISH positive, 88% were EGFR protein expression positive, and 13% were KRAS mutation positive. Compared with the overall study population, in which progression-free survival (PFS) [hazard ratio (HR) = 0.79] but not OS (HR = 0.91) were significantly improved with vandetanib, there was greater relative clinical benefit for patients with EGFR mutation-positive tumors [PFS HR 0.51, confidence interval (CI) 0.25-1.06 and OS HR 0.46, CI 0.14-1.57] and EGFR FISH-positive tumors (PFS HR 0.61, CI 0.39-0.94 and OS HR 0.48, CI 0.28-0.84). Similarly, patients with EGFR mutation or FISH-positive tumor samples who received vandetanib had an increased chance of objective tumor response (odds ratios 3.34, CI 0.8-13.89, and 3.90, CI 1.02-14.82, respectively). There did not appear to be benefit for vandetanib in patients with KRAS mutation-positive tumors. High EGFR gene copy number or activating EGFR mutations may identify patient subgroups who receive increased clinical benefit from vandetanib in combination with docetaxel in second-line NSCLC. NCT00312377.

Association of PD-L1 overexpression with activating EGFR mutations in surgically resected nonsmall-cell lung cancer

Recent clinical trials have shown that immune-checkpoint blockade yields a clinical response in a subset of individuals with advanced nonsmall-cell lung cancer (NSCLC). We examined whether the expression of programmed death-ligand 1 (PD-L1) is related to clinicopathologic or prognostic factors in patients with surgically resected NSCLC. The expression of PD-L1 was evaluated by immunohistochemical analysis in 164 specimens of surgically resected NSCLC. Cell surface expression of PD-L1 in NSCLC cell lines was quantified by flow cytometry. Expression of PD-L1 in tumor specimens was significantly higher for women than for men, for never smokers than for smokers, and for patients with adenocarcinoma than for those with squamous cell carcinoma. Multivariate analysis revealed that the presence of epidermal growth factor receptor gene (EGFR) mutations and adenocarcinoma histology were significantly associated with increased PD-L1 expression in a manner independent of other factors. Cell surface expression of PD-L1 was also significantly higher in NSCLC cell lines positive for activating EGFR mutations than in those with wild-type EGFR. The EGFR inhibitor erlotinib downregulated PD-L1 expression in the former cell lines but not in the latter, suggesting that PD-L1 expression is increased by EGFR signaling conferred by activating EGFR mutations. A high level of PD-L1 expression in resected tumor tissue was associated with a significantly shorter overall survival for NSCLC patients. High expression of PD-L1 was associated with the presence of EGFR mutations in surgically resected NSCLC and was an independent negative prognostic factor for this disease.

Abstract 1834: The molecular characters of acquired resistant non-small cell lung cancer cells to afatinib

Abstract [Background] The non-small cell lung carcinomas (NSCLCs) with activating epidermal growth factor receptor (EGFR) gene mutation show significant response to EGFR-tyrosine kinase inhibitors (TKIs). However, almost all of them acquire resistance to EGFR-TKIs due to various mechanisms, such as T790M mutation or MET amplification. Afatinib is an irreversible TKI for EGFR and HER2 and known to be effective to the EGFR T790M variant. However, a half of the patient responded afatinib acquire resistance by 12 months in clinical use. Thus, to unravel the mechanisms of the resistances and to overcome them are still important issues of EGFR-TKI treatment. In this study, we established various kinds of afatinib resistant cell lines with changing drug exposing condition as we previously reported (Shien K. et al Cancer Res. 2013). We also investigated these cell lines to understand mechanisms of afatinib resistances in NSCLC. [Materials and Methods] Afatinib resistant cell lines were established using four NSCLC cell lines with activating EGFR mutations by exposing afatinib with different procedures, escalation from 1 nM, escalation from 10 nM, intermittent 2 µM and continuous 2 µM procedures. These cell lines were investigated about previously reported resistant related features, T790M mutation, MET amplification, and epithelial to mesenchymal transition (EMT). ALDH1A1 and ABCB1 expression, which were putative stem cell markers, were also investigated. Proliferative inhibitions with various drugs were evaluated using MTS assay. [Results] There were no T790M mutations in all afatinib resistant cell lines. HCC827 sublines exposed afatinib with escalation from 1 nM and intermittent 2 µM, and HCC4011 sublines showed MET amplification. HCC827 sublines exposed afatinib with escalation from 10 nM and continuous 2 µM, and HCC4006 sublines showed EMT features. Furthermore, ALDH1A1 and ABCB1 expression were up-regulated in HCC827 afatinib resistant sublines with EMT features. Next, we examined the effect of afatinib or crizotinib for the afatinib resistant cell line with MET amplification. We found that combination therapy with afatinib and crizotinib was effective to the MET amplified cell. The combination exposure was continued to establish a resistant subline (HCC827-ACR) to combination therapy. The HCC827-ACR was also showed EMT features and up-regulation of stem cell markers. [Conclusions] As in the cases of reversible EGFR-TKI, MET amplification, EMT, and stem cell-like features were emerged in afatinib resistant cells. To develop strategies to resistant cells with stem cell-like property may be critical part to overcome EGFR-TKI resistance. Citation Format: Shinsuke Hashida, Shinichi Toyooka, Tomoaki Ohtsuka, Ken Suzawa, Kazuhiko Shien, Hiromasa Yamamoto, Junichi Soh, Hiroaki Asano, Kazunori Tsukuda, Shinichiro Miyoshi. The molecular characters of acquired resistant non-small cell lung cancer cells to afatinib. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1834. doi:10.1158/1538-7445.AM2014-1834

EGFR mutational genotyping of liquid based cytology samples obtained via fine needle aspiration (FNA) at endobronchial ultrasound of non-small cell lung cancer (NSCLC)

ObjectivesEpidermal growth factor receptor (EGFR) gene mutation status should be determined in all patients with advanced, non-squamous non-small cell lung carcinoma (NSCLC) to guide targeted therapy with EGFR tyrosine kinase inhibitors. EGFR mutations are commonly tested by Sanger sequencing or allele specific polymerase chain reaction (ASPCR) on formalin-fixed paraffin-embedded (FFPE) samples including cell blocks (CB) that may fail due to absence of tumor cells. The cell pellet from cytology specimens obtained at the time of endobronchial guided ultrasound fine needle aspiration (EBUS FNA) (EBUS-TBNA, transbronchial needle aspiration) represents an alternative resource for additional tissue. Here we demonstrate the utility of using the FNA cell pellet versus for the detection of EGFR mutations in NSCLC. Materials and methodsFor internal validation, 39 cytology samples from patients with NSCLC referred for EGFR testing were analyzed using the EGFR rotor-gene Q (RGQ) PCR assay (Qiagen).Thereafter, a consecutive series of 228 EBUS FNA samples were tested. ResultsThe ASPCR assay demonstrated acceptable intra-assay, inter-assay and inter-lot reproducibility, sensitivity, and specificity. For the consecutive series, only 6/228 (2.6%) failed analysis (5 due to insufficient DNA yield). Of 228 EBUS FNA cell pellets tested 32 (14.0%) demonstrated clinically relevant mutations. Results and conclusionASPCR can reliably detect EGFR gene mutations in FNA preparations from patients with NSCLC obtained at EBUS.

Visual DNA microarray for detection of epidermal growth factor receptor (EGFR) gene mutations

Objective. To develop a gold nanoparticle-based visual DNA microarray for simple and rapid screening of EGFR gene mutations. Methods. The DNA fragments contain epidermal growth factor receptor (EGFR) exons 18, 19, 20 and 21 were amplified by polymerase chain reaction (PCR) using biotin-modified primers. The amino-modified oligonucleotides were immobilized on glass surface, which were used as the capturing probes to bind the complement biotinylated target DNA. After the PCR product has been hybridized to the immobilized capture probe DNA on the glass slides, the Streptavidin-conjugated gold nanoparticles were introduced to the microarray via specific binding to 5ʹ-end biotin of the PCR products. The hybridization signal on array spots was enhanced and visualized by silver amplification. The EGFR mutation in 286 clinical samples from cancer patients were tested using the gold nanoparticle-based microarray and verified with Sanger DNA sequencing method. Results. A novel visual DNA microarray has been developed to detect EGFR mutations in tumor tissue specimens rapidly; its limit of detection (LOD) is up to 10−9 mol/L and distinguishes power to detect 5% gene mutation in the mixture samples. Conclusion. For its high specificity and sensitivity, simplicity, lower price and higher speed, the present visual mutation detecting technique has potential application in clinical fields.

Epidermal growth factor receptor (EGFR) mutations in lung cancer: preclinical and clinical data

Lung cancer leads cancer-related mortality worldwide. Non-small-cell lung cancer (NSCLC), the most prevalent subtype of this recalcitrant cancer, is usually diagnosed at advanced stages, and available systemic therapies are mostly palliative. The probing of the NSCLC kinome has identified numerous nonoverlapping driver genomic events, including epidermal growth factor receptor (EGFR) gene mutations. This review provides a synopsis of preclinical and clinical data on EGFR mutated NSCLC and EGFR tyrosine kinase inhibitors (TKIs). Classic somatic EGFR kinase domain mutations (such as L858R and exon 19 deletions) make tumors addicted to their signaling cascades and generate a therapeutic window for the use of ATP-mimetic EGFR TKIs. The latter inhibit these kinases and their downstream effectors, and induce apoptosis in preclinical models. The aforementioned EGFR mutations are stout predictors of response and augmentation of progression-free survival when gefitinib, erlotinib, and afatinib are used for patients with advanced NSCLC. The benefits associated with these EGFR TKIs are limited by the mechanisms of tumor resistance, such as the gatekeeper EGFR-T790M mutation, and bypass activation of signaling cascades. Ongoing preclinical efforts for treating resistance have started to translate into patient care (including clinical trials of the covalent EGFR-T790M TKIs AZD9291 and CO-1686) and hold promise to further boost the median survival of patients with EGFR mutated NSCLC.

Associations between epidermal growth factor receptor gene mutation and serum tumor markers in advanced lung adenocarcinomas: a retrospective study.

To investigate the associations between epidermal growth factor receptor (EGFR) gene mutations and serum tumor markers in advanced lung adenocarcinomas. We investigated the association between EGFR gene mutations and clinical features, including serum tumor marker levels, in 97 advanced lung adenocarcinomas patients who did not undergo the treatment of EGFR tyrosine kinase inhibitors. EGFR gene mutation was detected by real-time PCR at exons 18, 19, 20, and 21. Serum tumor marker concentrations were analyzed by chemiluminescence assay kit at the same time. EGFR gene mutations were detected in 42 (43%) advanced lung adenocarcinoma patients. Gender (P=0.003), smoking status (P=0.001), and abnormal serum status of carcinoembryonic antigen (CEA, P=0.028) were significantly associated with EGFR gene mutation incidence. Multivariate analysis showed the abnormal CEA level in serum was independently associated with the incidence of EGFR gene mutation (P=0.046) with an odds ratio of 2.613 (95% CI: 1.018-6.710). However, receiver operating characteristic (ROC) curve analysis revealed CEA was not an ideal predictive marker for EGFR gene mutation status in advanced lung adenocarcinoma (the area under the ROC curve was 0.608, P=0.069). EGFR gene mutation status is significantly associated with serum CEA status in advanced lung adenocarcinmoas. However, serum CEA is not an ideal predictor for EGFR mutation.

Clinicopathological features and EGFR gene mutation status in elderly patients with resected non-small-cell lung cancer.

BackgroundThe rapid aging of the population in Japan has been accompanied by an increased rate of surgery for lung cancer among elderly patients. It is thus an urgent priority to map out a treatment strategy for elderly patients with primary lung cancer. Although surgical resection remains standard treatment for early stage non–small-cell lung cancer (NSCLC), it is now essential to confirm the status of epidermal growth factor receptor (EGFR) gene mutations when planning treatment strategies. Furthermore, several studies have reported that EGFR mutations are an independent prognostic marker in NSCLC. However, the relations between age group and the molecular and pathological characteristics of NSCLC remain unclear. We studied the status of EGFR mutations in elderly patients with NSCLC and examined the relations of EGFR mutations to clinicopathological factors and outcomes according to age group.MethodsA total of 388 consecutive patients with NSCLC who underwent complete tumor resection in our hospital from 2006 through 2008 were studied retrospectively. Formalin-fixed, paraffin-embedded tissue sections were used to isolate DNA from carcinoma lesions. Mutational analyses of EGFR gene exons 19, 20, and 21 and KRAS gene exons 12 and 13 were performed by loop-hybrid mobility shift assay, a highly sensitive polymerase chain reaction-based method.ResultsEGFR mutations were detected in 185 (47.7%) and KRAS mutations were detected in 33 (8.5%) of the 388 patients. EGFR mutations were found in a significantly higher proportion of patients younger than 80 years (younger group; 178/359, 49.6%) than in patients 80 years or older (older group; 7/29, 24.1%) (P = 0.008). In contrast, KRAS mutations were more common in the older group (6/29, 20.7%) than in the younger group (27/359, 7.5%) (P = 0.014). The older group showed a trend toward a higher rate of 5-year overall survival among elderly patients with EGFR mutations (100%) than among those with wild-type EGFR (66.2%), but the difference was not significant.ConclusionsOur results suggest that the EGFR status of patients with NSCLC differs between patients 80 years or older and those younger than 80 years. EGFR mutation status might be a prognostic marker in elderly patients with completely resected NSCLC.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2407-14-610) contains supplementary material, which is available to authorized users.

Clinicopathological features associated with EGFR gene mutation in non-small cell lung cancer patients

To explore the clinicopathological features associated with epidermal growth factor receptor (EGFR) gene mutation in non-small cell lung cancer (NSCLC) patients. In this series, 677 NSCLC patients at lung disease center during June 2010 through July 2013 were included. The EGFR gene type was determined through pyrosequencing assay. The factors associated with EGFR gene mutation were explored by comparing their clinicopathological features. Among them, 313 (46.2%) patients had mutant EGFR. It happened more frequently in females (60.4% vs 33.3%), non-smoker (54.8% vs 32.4%), stagesIa-IIIa (51.1% vs 38.6%), well-differentiated (81.1% vs 46.1%) and adenocarcinoma (50.7% vs 15.3%) patients than in males, smoker, stages IIIb-IV, poorly differentiated and non-adenocarcinoma counterparts (all P < 0.05). However, the mutation rate was lower in patients with AB blood type (25.0%) than those with other blood types (type A 49.4%, type B 46.0%, type O 50.0%) (all P < 0.05). The patients with mutant EGFR gene had a higher level of serum carcino-embryonic antigen (CEA) than those with wild-type EGFR gene (114.5 vs 41.8 µg/L, P = 0.038). The female, non-smoker, stagesIa-IIIa, well-differentiated and adenocarcinoma patients of NSCLC have significantly higher incidence of EGFR gene mutation while mutation is rare in those with AB blood type. And pathology, differentiation and blood type are independent factors affecting EGFR mutation.

The efficacy of EGFR gene mutation testing in various samples from non-small cell lung cancer patients: a multicenter retrospective study.

Introduction Testing for the epidermal growth factor receptor (EGFR) gene mutations requires considerable multidisciplinary experience of clinicians (for appropriate patient selection), pathologists (for selection of appropriate cytological or histological material) and geneticists (for performing and reporting reliable molecular tests). We present our experience on the efficacy of routine EGFR testing in various types of tumor samples and the frequency of EGFR mutations in a large series of Polish non-small cell lung cancer (NSCLC) patients. MethodsDeletions in exon 19 and substitution L858R in exon 21 of EGFR gene were assessed using real-time PCR techniques in 1,138 small biopsies or cytological specimens and in 1,312 surgical samples. ResultsOut of 2,450 diagnostic samples (containing >10 % of tumor cells), the occurrence of EGFR gene mutations was 9 %; more frequently in women (13.9 %) and adenocarcinoma patients (10 %), particularly with accompanying expression of TTF1 (13.0 %). The frequency of EGFR gene mutations was similar in cytological and histological specimens, and in primary and metastatic lesions, and did not depend on the percentage of tumor cells and quality of isolated DNA. Cytological or small biopsy, compared to surgical specimens showed lower percentage of tumor cells, with no impact on the quality of real-time PCR assay.ConclusionCytological and small biopsy samples with low (10–20 %) content of tumor cells and specimens from metastatic lesions are a sufficient source for EGFR mutation testing in NSCLC patients. The incidence of EGFR gene mutations in examined population was similar to those reported in other Caucasian populations.

Surrogate endpoints for overall survival in advanced non-small-cell lung cancer patients with mutations of the epidermal growth factor receptor gene.

Subsequent therapies confound the ability to discern the effect of first-line chemotherapy on overall survival (OS). We investigated whether progression-free survival (PFS), post-progression survival (PPS) and tumor response were valid surrogate endpoints for OS following first-line chemotherapy in individual patients with advanced non-small-cell lung cancer (NSCLC) harboring sensitive epidermal growth factor receptor gene mutations. We retrospectively analyzed 35 patients with advanced NSCLC treated with first-line gefitinib. The associations of PFS, PPS and tumor response with OS were analyzed. PPS was found to be strongly correlated with OS, unlike PFS and tumor shrinkage. The factors significantly associated with PPS were performance status (PS) after first-line treatment, best response to second-line treatment and number of regimens used after disease progression. PPS may be a surrogate for OS in this patient population and further therapy after disease progression following first-line chemotherapy may significantly affect OS. However, a larger study is required to validate these results.

Tailored treatment with targeted therapies in non-small cell lung cancer (NSCLC) based on the epidermal growth factor receptor gene (EGFR) mutation testing.

e19150 Background: About 10-20% of NSCLC tumors harbor activating EGFR mutations. The introduction of new therapies targeting EGFR has achieved a significant impact on survival and their use has re...