Immunohistochemistry as a tool for identifying EGFR amplification in CNS tumors.

1226O - Biomarker Analyses and Overall Survival (OS) from the Randomized, Placebo-Controlled, Phase 3, Fastact-2 Study of Intercalated Erlotinib with First-Line Chemotherapy in Advanced Non-Small-Cell Lung Cancer (NSCLC)

7674 Background: The EGFR tyrosine kinase inhibitor erlotinib significantly prolonged survival and improved QoL in relapsed NSCLC patients (pts) (Shepherd et al. NEJM 2005;353:123). TRUST is an ongoing, single arm, international, multicenter trial providing erlotinib access to pts with advanced NSCLC (>6,500 enrolled). Methods: Stage IIIb/IV NSCLC; failed (1–2 regimens) or unsuitable for chemotherapy. Pts received erlotinib 150 mg/day p.o. until progression or unacceptable toxicity. Pts were assessed for response, progression free survival (PFS), overall survival (OS) and safety. Where possible, tumor tissue samples were collected from German centers and centrally assessed by; immunohistochemistry (IHC; EGFR, pMAPK), fluorescence in-situ hybridization (FISH; EGFR gene copy number), and DNA sequencing (EGFR, KRAS gene mutations). Results were assessed for correlations with treatment benefit. Results: Nov 2006, biomarker data were available for 287 of 393 German pts; median age 65 yrs (range 33–90). Baseline characteristics (%): male/female (59/41); Caucasian/Oriental/no data (99/1/<1); non-smoker/former or current smoker (25/75); adenocarcinoma/squamous cell/BAC/large cell/other/no data (57/33/3/2/1/4). 40% received erlotinib 2nd line. Of 230 pts with response data, 7.4% had a complete or partial response. Median PFS was 11.0 weeks (95% CI: 9.0–13.1). Preliminary analyses showed EGFR IHC+ (=10% staining; 223/278) pts (vs EGFR IHC-) had longer OS (HR=0.75; p=0.1) and PFS (HR=0.71; p=0.03). OS (HR=0.53; p=0.02) and PFS (HR=0.38; p=0.0001) were significantly prolonged in EGFR FISH+ (28/133) vs FISH- pts. Pts with KRAS mutations (17/107) had shorter OS (HR=1.5; p=0.18) and PFS (HR=1.6; p=0.08) vs wildtype. pMAPK+ status (29/108) was associated with shorter OS (HR=2.6; p<0.0001) and PFS (HR=1.6; p=0.0007). Conclusion: As TRUST is a single arm study, conclusions on the prognostic or predictive significance of these biomarkers cannot be drawn. Erlotinib treated NSCLC pts with EGFR IHC+, EGFR FISH+ or pMAPK- tumors may have better outcomes than those with EGFR IHC-, EGFR FISH-, and pMAPK+ tumors, but to prospectively assess the predictive value of these biomarkers, a randomized phase III study is ongoing (BO18192, SATURN). [Table: see text]

7003 Background: Erlotinib produces dramatic responses in a subset of patients with NSCLC. Mutations in the EGFR tyrosine kinase domain, EGFR amplification or polysomy and EGFR overexpression on immunohistochemistry have all been associated with sensitivity and benefit; pts with KRAS mutation are commonly resistant to this agent. These correlative studies were prospectively undertaken to characterize the ability of these markers to predict response rate, time to progression and survival in pts with BAC treated with the EGFR-TKI, erlotinib. Methods: One hundred and two patients received erlotinib as part of a phase II trial in BAC (Kris, Proc ASCO 2005); 84 had one or more correlative studies completed. Analysis of EGFR exons 19 and 21 (n=82) (Pao, et al PNAS 2004), EGFR IHC (n=62) (DAKO) was performed and EGFR copy number was determined by chromogenic in situ hybridization (CISH) (n=74) (Zymed); detection of ≥ 4 signals per cell was considered evidence of amplified copy number. KRAS exon 2 (n=79) testing was performed by direct sequencing. Fisher’s exact test was used to study the association of each feature in pts with partial response or no partial response. Time to progression and survival were analyzed with log-rank test. Results: See table below. Conclusions: 1) EGFR exon 19 or 21 mutation is a powerful predictor of response and TTP but not OS in pts with BAC treated with erlotinib. 2) CISH ≥4 is associated with response and improved TTP but not OS. 3) Patients with both EGFR mutation and amplification fare well supporting the concept of “oncogene addiction”; erlotinib should be considered as initial therapy in this population. 4) EGFR amplification without mutation is uncommon. 5) There is no clear utility of EGFR IHC in clinical decision making. 6) The presence of KRAS mutation predicts resistance to erlotinib. Supported, in part, by Genentech. [Table: see text] [Table: see text]

BackgroundThe goal of this study was to investigate ERBB2(HER2) and EGFR gene amplification and protein expression in gastric cancer. Fluorescence in situ hybridization (FISH) and immunohistochemistry were used to analyze ERBB2 and EGFR gene amplification and protein expression in 69 cases of gastric cancer.ResultsFISH analysis revealed that 20.3% of the cases exhibited ERBB2 gene amplification. Increases in ERBB2 copy number and gene amplification were present in 52.2% of the samples. Expression of the ERBB2 protein was observed in 42.0% of cases. FISH analysis detected EGFR gene amplification in 29.0% of samples. Increases in EGFR copy number and gene amplification occurred in 57.9% of samples, and EGFR protein expression was present in 52.2% of samples. Both ERBB2 and EGFR gene amplification were 3 cases (4.3%), but abnormalities in both ERBB2 and EGFR gene copy number were present 36.2% of samples. ERBB2 and EGFR gene amplification were significantly associated with the depth of tumor invasion (P < 0.05) and lymph node metastasis (P < 0.05), but not with sex, age, or histological type (P > 0.05).ConclusionsOur data indicated that ERBB2 and EGFR genetic abnormalities were associated with the prognosis of gastric cancer. Clinical assessment of ERBB2 and EGFR amplification may represent an important factor for the development of personalized treatment programs for gastic cancer.

BackgroundApproximately 50 % of gastric adenocarcinomas belong to a molecular subgroup characterised by chromosomal instability and a strong association with the intestinal histological subtype. This subgroup typically contains alterations in the receptor tyrosine kinase–RAS pathway, for example EGFR or HER2 gene amplifications leading to protein overexpression. In clinical practice, HER2 overexpressing metastatic gastric cancer is known to respond to treatment with anti-HER2 antibodies. By contrast, anti-EGFR antibodies have not been able to provide survival benefit in clinical trials, which, however, have not included patient selection based on the histological subtype or EGFR gene copy number analysis of the tumours. To examine the role of EGFR as a potential biomarker, we studied the prevalence, clinicopathological associations as well as prognostic role of EGFR and HER2 expression and gene amplification in intestinal adenocarcinomas of the stomach, gastro-oesophageal junction and distal oesophagus.MethodsTissue samples from 220 patients were analysed with EGFR and HER2 immunohistochemistry. Those samples with moderate/strong staining intensity were further analysed with silver in situ hybridization to quantify gene copy numbers. The results were associated with clinical patient characteristics and survival.ResultsModerate/strong EGFR protein expression was found in 72/220 (32.7 %) and EGFR gene amplification in 31/220 (14.1 %) of the tumours, while moderate/strong HER2 protein expression was detected in 31/220 (14.1 %) and HER2 gene amplification in 29/220 (13.2 %) of the tumours. EGFR and HER2 genes were co-amplified in eight tumours (3.6 %). EGFR gene amplification was more common in tumours of distal oesophagus/gastro-oesophageal junction/cardia than in those of gastric corpus (p = 0.013). It was associated with shortened time to cancer recurrence (p = 0.026) and cancer specific survival (p = 0.033).ConclusionsEGFR gene amplification is relatively common in intestinal adenocarcinomas and associates with decreased survival. It is rarely concurrent with HER2 gene amplification, suggesting that anti-EGFR therapies might be applicable to some patients not eligible for anti-HER2 treatment. Analogous to HER2 testing, determination of EGFR gene amplification status in concert with immunohistochemistry could improve the specificity of patient selection when investigating the possible benefits of anti-EGFR therapies in the treatment of gastric adenocarcinomas.

7651 Background: Recent studies have examined potential predictive markers in NSCLC patients (pts) treated with EGFR tyrosine kinase inhibitors. However, few data are available on inter-relationships between different markers. Clinical and molecular markers were analyzed for patients from TRUST, an open label, non-randomized trial initiated to provide erlotinib access to pts with advanced NSCLC. Methods: 393 German pts (99% Caucasian) with stage IIIb/IV NSCLC were included. Markers/characteristics assessed were: EGFR (282 pts) and phosphorylated MAPK (pMAPK; 109 pts) using immunohistochemistry (IHC; positive status was defined as: ≥10% of tumor cells with any membrane staining for EGFR; and H-score ≥200 for pMAPK), EGFR gene copy number (135 pts) using fluorescence in-situ hybridization (FISH), EGFR mutations (86 pts), KRAS mutations (108 pts), tumor type (281 pts), smoking status (392 pts) and gender (393 pts). Results: EGFR FISH+ pts were likely to also be EGFR IHC+: 92.9% (26/28) of EGFR FISH+ pts were EGFR IHC+, and 92.6% of EGFR IHC- pts were also EGFR FISH- (p&lt;0.1). pMAPK expression status was not related to other markers. 15.7% (17/108) pts had KRAS and 7.0% (6/86) had EGFR mutations; no pts had mutations in both genes, indicating that these mutations might be mutually exclusive. Both KRAS mutations and histology were associated with smoking status. 94.1% (16/17) pts with KRAS mutations and 91.6% (87/95) pts with squamous-cell carcinoma were smokers. In female pts, the occurrence of adenocarcinoma was significantly higher (73.6% vs 55.4% in males; p&lt;0.001), possibly influenced by a lower incidence of smokers in this group (51.3% vs 92.2% in males; p&lt;0.001). Conclusions: The availability of a large number of tumor samples from the TRUST study, and assessment of a broad range of markers allows investigation of relationships between various tumor/patient characteristics. Understanding these complex inter-relationships may shed light on the role of each marker. Specific combinations of markers may prove useful in predicting clinical benefit from erlotinib. As the study is ongoing, additional data will be available and presented. No significant financial relationships to disclose.

7548 Background: Cetuximab improved overall survival (OS) in first-line advanced NSCLC in a pivotal trial including all histologies (FLEX). Other phase II/III trials have tested cetuximab with several platinum doublets. Putative predictive-marker candidates have been explored retrospectively in some of these trials. Methods: Investigators have evaluated comprehensively the retrospective data available to date from studies of cetuximab plus chemotherapy (CT), analyzing the correlation between biomarker status (K-Ras and EGFR mutations, EGFR protein expression by IHC and EGFR gene copy number [GCN] by FISH) and incremental benefit from cetuximab (phase III and randomized phase II studies), or overall outcome (single arm phase II trials). Results: Tissue collection was not mandatory and tumor-sample ascertainment rates ranged from 20%-30% (except for mandatory tissue collection for EGFR IHC testing in FLEX). Biomarker evaluable populations were representative of ITT populations for baseline factors, although their outcomes differed in some trials. Response rates (RR) in single arm trials were similar regardless of EGFR or K-Ras mutational status. EGFR FISH positivity was associated with better outcomes in the S0342 trial of sequential or concomitant cetuximab plus CT, but this effect was not consistently found in other randomized trials. In randomized phase III trials, benefit from the addition of cetuximab to CT was seen regardless of K-Ras or EGFR mutations, while results for EGFR GCN by FISH have been conflicting. EGFR IHC was a selection criterion in some trials; in the others, only 15% of patients tested negative, data are therefore insufficient to rule out a predictive effect. In randomized studies, the magnitude of benefit from cetuximab seems similar regardless of EGFR IHC expression-based selection. Conclusions: No predictive biomarker for cetuximab benefit in NSCLC has yet been confirmed. Benefit from cetuximab was observed regardless of K- Ras mutations, a strong predictor of lack of cetuximab benefit in CRC, or EGFR mutational status. EGFR FISH is being prospectively evaluated in S0819. Additional studies are ongoing to identify novel predictive biomarkers of cetuximab benefit in NSCLC. Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Bristol-Myers Squibb, Infinity Pharmaceuticals, Merck KGaA, Response Genetics Amgen, AstraZeneca, Biodesix, Boehringer Ingelheim, Bristol-Myers Squibb, Genentech, GlaxoSmithKline, ImClone Systems, Lilly, Merck, Merck Serono, Novartis, Pfizer, Roche, sanofi-aventis Bristol-Myers Squibb, Infinity Pharmaceuticals AstraZeneca, Lilly, Merck KGaA, Merck Serono, None, Roche Abbott Laboratories, Bristol-Myers Squibb, Genentech, ImClone Systems, Lilly, Merck, Merck KGaA, Novartis, Pfizer

10502 Background: In metastatic colorectal cancer (MCRC), no molecular predictive markers to cetuximab response have been yet established. The aim was to evaluate whether KRAS gene mutations, EGFR immunochemistery (IHC) and EGFR gene copy number correlate with response to cetuximab. Methods: 59 patients with MCRC treated by cetuximab between July 2004 and December 2005 were retrospectively included. Clinical data were collected and tumour response was evaluated according to RECIST criteria. EGFR IHC was performed using the Dako kit. The EGFR gene copy number was determined by FISH (Fluorescence in-Situ Hybridization). Detection of KRAS gene mutations on exon 2 was performed by sequencing of extracted paraffin-embedded DNA and then by 2 methods, SNaPshot and PCR-LCR, specifically developed to detect small fractions of mutated tumor cells. Response to cetuximab was studied according to clinical data, IHC, FISH and KRAS mutation analysis using the Fischer exact test. Predictive factors of response were determined by logistic regression. Skin reactions were collected but not considered for this analysis as regards the lack of accurate grading in a retrospective study. Times to progression (TTP) were calculated using the Kaplan-Meier method and compared with log-rank test. Results: 12 patients (20.3%) responded to cetuximab (2 patients with complete response and 10 patients with partial response), 19 (32.2%) had stable disease and 28 (47.5%) were in disease progression. A KRAS mutation was detected in 22/59 tumours and, in 6 cases, was missed by sequencing analysis but detected using the SNaPshot and PCR-LCR assays. No KRAS mutation was found in responders patients. KRAS mutation was associated with disease progression (p = 0.0005) and TTP was significantly decreased in mutated KRAS patients (3 vs 5.5 months, p = 0.015). There was no correlation between EGFR IHC and cetuximab response. No EGFR gene copy number increase was detected in responders patients. Predictive factors of cetuximab resistance were KRAS mutation (p=0.003; OR:0.10; 95IC:0.22–0.40) and age&lt;60 (p=0.024; OR:0.13; 95IC:0.02–0.77). Conclusions: KRAS mutation is highly predictive of cetuximab resistance in MCRC. Our study also highlights the need of sensitive methods to ensure an efficient mutation detection. No significant financial relationships to disclose.

BACKGROUND: The development of minimally-invasive methods to detect and monitor tumors continues to be a major challenge in oncology. We used digital PCR-based technologies to evaluate the ability of circulating tumor DNA (ctDNA) to detect tumors in 640 patients with various cancer types. In particular we studied the plasma of 14 medulloblastoma, 13 WHO grade 2-3 glioma and 14 WHO grade IV astrocytoma cases for levels of ctDNA. METHODS: The basis of our approach is to differentiate DNA shed by normal cells from DNA derived from tumor cells. In order to distinguish the two populations of cell-free DNA, we first identify a tumor-specific alteration. We then query for that exact mutation in matching plasma from the same patient to generate a personalized tumor biomarker. Only DNA derived from the tumor will harbor the genetic alteration. We initially use targeted, exomic, or whole genome sequencing to identify sequence or structural alterations in tumor tissues of 410 individuals. DNA was extracted from less than 5 ml of plasma in each case. The majority of plasma samples were queried for levels of ctDNA using a high fidelity next-generation sequencing approach coined Safe-SeqS. RESULTS: We found that at least one tumor-specific mutant molecule could be identified in <5 mL of plasma in >75% of patients with advanced ovarian, colorectal, bladder, gastroesophoageal, pancreatic, breast, melanoma, hepatocellular and head and neck cancers, but in less than 50% of primary brain, renal, prostate, or thyroid cancers. Approximately 40% of medulloblastoma and 10% of low or high grade glioma cases had detectable levels of ctDNA. In patients with localized non-CNS tumors, ctDNA was detected in 73%, 57%, 48% and 50% of patients with colorectal cancer, gastroesophageal cancer, pancreatic cancer, and breast adenocarcinoma, respectively. Finally, we assessed whether ctDNA could provide clues into the mechanisms underlying resistance to epidermal growth factor receptor (EGFR) blockade in 24 colorectal cancer patients who objectively responded to therapy but who subsequently relapsed. Twenty-three (96%) of these patients developed one or more mutations in genes involved in the mitogen-activated protein kinase (MAPK) pathway. CONCLUSIONS: Taken together, these data suggest that ctDNA is a sensitive, specific and robust biomarker that can be used for a variety of clinical and research purposes in patients with several multiple different types of cancer. For individuals with CNS neoplasms, alternate strategies may need to be developed in order to detect cell-free tumor derived DNA at levels that are clinically meaningful. ABSTRACT CATEGORY: Neuropathology & Tumor Biomarkers.

There is a growing interest in evaluating molecular markers as predictors of response to new generation of targeted cancer therapies. One of such areas is biological therapy targeting epidermal growth factor receptor gene (EGFR) in lung cancer. The testing of tumor tissue is focused on specific EGFR mutations and EGFR gene amplification, since tumors exhibiting positivity of either of the two marker types are highly sensitive towards the treatment. Although traditional methods of DNA sequencing and fluorescence in situ hybridization are still in use for the detection of EGFR mutations and gene amplification, respectively, there is a need for new dedicated techniques with the primary emphasis on simplicity, sensitivity, speed and cost effectiveness. The main purpose of this work was to integrate diverse assays for both EGFR tests onto a single platform to eliminate the need for different instruments and separate processing. We demonstrate a chip capillary electrophoresis (chipCE) application for EGFR mutation detection by a combination of fragment analysis and denaturing CE along with multiplex ligation-dependent probe amplification (MLPA) for evaluation of EGFR amplification. All separations are carried out in denaturing sieving polymer on a modified Bioanalyzer 2100 chipCE instrument running at temperatures of up to 65°C. The main strength of the resulting high-resolution chipCE application is in its simplicity, speed of analysis and minimal amount of sample required for complete testing of EGFR status. Such an approach could potentially fit medium throughput laboratories providing molecular pathology services for clinical oncologists with fast turnaround times and limited consumption of tissue material.

EGFR-directed therapies are used to treat patients with advanced head and neck squamous cell carcinoma (SCC). As it is still unclear whether or not EGFR amplification represents an early or late event in head and neck SCC progression, we aimed to determine the frequency of abnormalities of EGFR protein and gene copy numbers in early oral SCC. A tissue microarray of cancer tissue from 120 patients with pT1/2 oral SCC was constructed. We investigated EGFR protein expression by immunohistochemistry. EGFR gene copy enumeration was performed using fluorescence in-situ hybridization (FISH) and the novel automated silver in-situ hybridization (SISH) technology. Of early oral SCC, 19.3% showed high, 57.1% moderate and 23.6% low EGFR expression. EGFR amplification/polysomy was identified in 8% and 9% of cases by FISH and SISH, respectively. EGFR-SISH had a high concordance with EGFR-FISH (kappa value = 1.0), and both methods showed high conformity with EGFR immunohistochemistry (P = 0.001 and P = 0.006, respectively). No correlation was found of EGFR protein expression or gene amplification status with pT or pN stage. Only a small subgroup of early oral SCC is characterized by EGFR amplification, which can be identified reliably using EGFR-SISH technology. This finding suggests that EGFR gene amplification mostly occurs in advanced stages of oral SCC.

IntroductionCentral nervous system (CNS) tumors comprise 15–20% of all malignancies occurring in childhood and adolescence. Previous researches have shown that overexpression and amplification of the AURKA gene could induce multiple human malignancies, with which the connection of CNS tumor susceptibility has not been extensively studied.Material and methodsIn this study, we assessed whether and to what extent AURKA gene single nucleotide polymorphisms (SNPs) (rs1047972 C > T, rs2273535 T > A, rs8173 G > C) were associated with CNS tumor susceptibility, based on a case–control analysis in 191 CNS tumor patients and 248 controls. We determined this correlation using odds ratios (ORs) and 95% confidence intervals (CIs).ResultsAURKA gene rs8173 G > C exhibited a crucial function to CNS tumor susceptibility fall-off (GC/CC vs. GG: adjusted OR = 0.68, 95% CI = 0.46–0.998, P = 0.049). In addition, the combined effect of lowering the risk of developing CNS tumors was more pronounced in carriers with 3 protective genotypes than others (adjusted OR = 0.55, 95% CI = 0.31–0.98, P = 0.044). Further stratification analysis illustrated that the existence of rs8173 GC/CC and three protective genotypes lowered CNS tumor risk in some subgroups.ConclusionsOur research suggested that the AURKA gene rs8173 G > C could significantly reduce CNS tumor susceptibility in Chinese children. More functional experiments are needed to explore the role of the AURKA gene rs8173 G > C.

Myocardial infarction is a major cause of death and disability worldwide. Coronary atherosclerosis is a chronic disease with stable and unstable periods. During unstable periods with activated inflammation in the vascular wall, patients may develop a myocardial infarction. Myocardial infarction may be a minor event in a lifelong chronic disease, it may even go undetected, but it may also be a major catastrophic event leading to sudden death or severe hemodynamic deterioration. A myocardial infarction may be the first manifestation of coronary artery disease, or it may occur, repeatedly, in patients with established disease. Information on myocardial infarction attack rates can provide useful data regarding the burden of coronary artery disease within and across populations, especially if standardized data are collected in a manner that demonstrates the distinction between incident and recurrent events. From the epidemiological point of view, the incidence of myocardial infarction in a population can be used as a proxy for the prevalence of coronary artery disease in that population. Furthermore, the term myocardial infarction has major psychological and legal implications for the individual and society. It is an indicator of one of the leading health problems in the world, and it is an outcome measure in clinical trials and observational studies. With these perspectives, myocardial infarction may be defined from a number of different clinical, electrocardiographic, biochemical, imaging, and pathological characteristics. In the past, a general consensus existed for the clinical syndrome designated as myocardial infarction. In studies of disease prevalence, the World Health Organization (WHO) defined myocardial infarction from symptoms, ECG abnormalities, and enzymes. However, the development of more sensitive and specific serological biomarkers and precise imaging techniques allows detection of ever smaller amounts of myocardial necrosis. Accordingly, current clinical practice, health care delivery systems, as well as epidemiology and clinical trials all require a …

The purpose of the study: Evaluation tumor cell number with CCND1 and EGFR gene amplification and its correlation with Cyclin D1 and EGFR protein expression in squamous cell carcinoma of the tongue. Material and methods. For cytogenetic examination, smears from 19 cases of squamous tongue cancer were used, after which a biopsy of the corresponding tumor sites was performed. The cytogenetic study was performed by interphase fluorescent in situ hybridization (FISH). The immunohistochemical study was performed using antibodies to Cyclin D1 and EGFR. Results. Amplification of the EGFR and CCND1 genes was detected in the tumor cells of all samples. The number of cells with amplification of the studied genes occupied a wide range. Thus, for the EGFR gene, it ranged from 1 to 59 cells, and for the CCND1 gene, it ranged from 1 to 87 cells. In 100 % of observations, EGFR and CCND1 amplification were combined. Diffuse, mostly moderate EGFR expression was detected in 17 (89 %) of the 19 observations, and focal weak expression was detected in two observations (11 %). Cyclin D1 expression in all analyzed observations was focal, weak and moderate. Conclusion. The cytogenetic features of the tongue squamous cell carcinoma are wide range of cells with amplification of EGFR and CCND1 genes, amounting to 1–59 and 1–87 cells, respectively. Tumors with EGFR amplification correspond to diffuse EGFR protein expression in 89% of cases and focal expression in 11% of cases. Tumors with CCND1 amplification correspond to the focal expression of Cyclin D1 in all observations.

Identification of critical genes which play pivotal roles in controlling tumor growth and survival will establish the basis for developing therapeutic targets. In this study, we focused on frequencies of EGFR, ErbB2 and MET gene amplification in gastric cancer patients to develop personalized medicine to improve the treatment. EGFR, ErbB2 and MET gene amplification, and mRNA expression were analyzed by the quantitative Real-Time PCR in paraffin-embedded samples from 115 patients with gastric cancer. EGFR, ErbB2 and MET genes were amplified in 11.3% (13/115), 6.1% (7/115) and 19.1% (22/115) of cancerous specimens, respectively. The correlation coefficient test clearly indicated that gene amplification in these three genes was positively correlated with mRNA transcription (EGFR: R=0.631, p=0.009; ErbB2: R=0.652, p=0.023; MET: R=0.715, p<0.001). EGFR and MET gene amplification was significantly associated with Ki-67 MI (p=0.022 and p=0.015). MET amplification was also significantly associated with age of≥60years (p=0.021) and tumor size of≥5cm (p=0.032). MET amplification, but not EGFR and ErbB2, was a significant prognostic factor in poor survival among patients with gastric cancer. EGFR, ErbB2 and MET genes are frequently amplified in gastric carcinoma. EGFR, ErbB2 and MET gene amplification is positively correlated with mRNA transcription. MET gene amplification correlates with a poor prognosis and poor survival in gastric carcinomas.