Applicable Value of AMSS-PCR in Lung Cancer Gene Mutation Detection / 中国肺癌杂志

BACKGROUND@#The detection of driver oncogenes of lung cancer is of great importance. There are various gene detection techniques nowadays which are different from each other. We carried out this study to investigate the specificity and sensitivity of assay panels based on an Amplification Refractory Mutation System-polymerase chain reaction (ARMS-PCR) technique of Amplification Mutation Specific System (AMSS) in detection of lung cancer gene mutation. To estimate the applicable value of assay panels in clinical settings.@*METHODS@#We collected cancer tissue specimens or fluid specimens from 309 patients. Mutation results were presented for those samples previously detected by ARMS-PCR. In comparison, we carried out AMSS-PCR using (epidermal growth factor receptor, EGFR) assay panel and Six-Alliance assay panel as well as Sanger sequencing. Software SPSS 22.0 (SPSS IBM) was used for statistical analysis.@*RESULTS@#The rates of consistency between the results by assay panels and Sanger sequencing or ARMS-PCR were 97.41% and 97.73%, respectively. Besides, EGFR assay panel had higher consistency rates with other detection methods than Six-Alliance assay panel. As for consistency test, the Kappa values of assay panels with Sanger sequencing, assay panels with ARMS-PCR, and ARMS-PCR with Sanger sequencing were 0.946, 0.953, and 0.913, respectively. The receiver operating characteristic curve (ROC) area under curve (AUC) of assay panels was 0.976 referring to Sanger sequencing, and 0.975 as ARMS-PCR was referred to.@*CONCLUSIONS@#AMSS-PCR can make an optimal cancer gene mutation detection method for clinical settings.

Evaluation of epidermal growth factor receptor mutations based on mutation specific immunohistochemistry in non-small cell lung cancer: A preliminary study.

Background & objectives: Studies have shown that immunohistochemical (IHC) staining using epidermal growth factor receptor (EGFR) mutation specific antibodies, is an easy and cost-effective, screening method compared with molecular techniques. The purpose of present study was to assess the percentage positivity of IHC using EGFR mutation specific antibodies in lung biopsy samples from patients with primary lung adenocarcinoma (ADC). Methods: Two hundred and six biopsies of primary lung ADC were subjected to EGFR mutation specific antibodies against del E746-A750 and L858R. Detection of EGFR mutation done by high resolution melting analysis (HRM) was used as gold standard. A concordance was established between molecular and IHC results. Frequency of IHC positivity was assessed. Results: Of the 206 patients, 129 were male and 77 were female patients, with a mean age of 54.1 yr. Fifty five (26.6%) patients (36 men; 19 women) showed positivity for IHC of del E746-A750 (33) and L858R (22). HRM results were available in 14 patients which showed EGFR mutations in correspondence with del E746-750 or L858R in 64.2 per cent cases. Positive cases on HRM were further confirmed by DNA sequencing and fragment analysis. Three patients showed exon20 variation. Two cases were negative for mutation. The genotype of del E746-750 mutation was more common than L858R. A concordance was established between molecular mutation and IHC in 85.7 per cent cases. Interpretation & conclusions: In this preliminary study from India mutation specific IHC was used for assessment of mutation status of EGFR. Although the number tested was small, a good concordance was observed between molecular EGFR mutation and IHC expression. IHC methodology is a potentially useful tool to guide clinicians for personalized treatment in lung ADC, especially where facilities for molecular analysis are not readily available and for use in small biopsies where material is scant for molecular tests.

Identification of EGFR Mutations by Immunohistochemistry with EGFR Mutation-Specific Antibodies in Biopsy and Resection Specimens from Pulmonary Adenocarcinoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Mutation-specific antibodies have recently been developed for identification of epidermal growth factor receptor (EGFR) mutations by immunohistochemistry (IHC). This study was designed to investigate whether the type of specimen (biopsy vs. resection) would make a difference in determining mutation status by IHC, and to evaluate whether biopsies are suitable for detection of mutant EGFR protein. MATERIALS AND METHODS: IHC was performed using mutation-specific antibodies for E746-A750 deletion (DEL) and L858R point mutation (L858R) in biopsies and tissue microarrays of resected tumors from 154 patients with pulmonary adenocarcinoma. Results were then compared with DNA sequencing data. RESULTS: Molecular-based assays detected EGFR mutations in 62 patients (40.3%), including 14 (9.1%) with DEL, and 31 (20.1%) with L858R. IHC with two mutation-specific antibodies showed a homogeneous staining pattern, and correctly identified EGFR mutation status in 89% (137/154). Overall (biopsy/resection) sensitivity, specificity, positive predictive value, and negative predictive value were 75.6% (78.3%/72.7%), 94.5% (90.9%/96.3%), 85% (78.3%/88.9%), and 90.4% (90.9%/89.7%), respectively. CONCLUSION: Our data showed that IHC using EGFR mutation-specific antibodies is useful for detection of EGFR mutations with high specificity and good sensitivity not only for resection specimens but also for biopsy materials. Therefore, IHC using EGFR mutation-specific antibodies may preclude a second biopsy procedure to obtain additional tissues for identification of EGFR mutations by molecular assays in biopsies from advanced cancer, particularly when tumor cells in the samples are limited.

Expression of EGFR mutation-specific antibody and its significance in lung adenocarcinoma / 临床与实验病理学杂志

Purpose To investigate the expression and significance of epiderma1 growth factor receptor( EGFR)mutation-specific anti-bodies in 1ung adenocarcinoma. Methods Immunohistochemica1( IHC)technique was used to detect the expression of EGFR muta-tion-specific antibodies(EGFR-19,EGFR-21)and EGFR tota1 protein antibody(EGFR-P)in 171 cases of 1ung adenocarcinoma with resected specimens,and EGFR gene mutation was a1so performed by amp1ification refractory mutation aystem-PCR( ARMS-PCR). The expression of EGFR-19,EGFR-21 and EGFR-P mutant proteins was compared with EGFR gene mutation and their re1ationship with histo1ogica1 c1assification and c1inica1 characteristics were ana1yzed. Results The expression of EGFR mutant protein was corre1ated with the poor differentiation group inc1uding micropapi11ary and so1id predominant types( P=0. 021 ). EGFR-21 high expression was re1ated to p1eura1 invasion(P=0. 005). The coherence of IHC(with EGFR-19/21 antibodies)and ARMS-PCR was existed(Kappa>0. 4 ). Taking ARMS-PCR as a standard,the sensitivity and specificity of EGFR-19 and EGFR-21 were 65. 0% and 89. 4%, 70. 0% and 97. 6%,respective1y. Conclusions Expression of EGFR mutation-specific antibodies is associated with poor differentia-tion and p1eura1 invasion. It suggests a worse prognosis indicator in 1ung adenocarcinoma. Because of the coherence with ARMS-PCR, using IHC with mutation-specific antibodies to detect the mutant proteins of EGFR-19/21 may act as a pre1iminary screening method of EGFR gene mutation.