{rfName}
A

Indexed in

License and use

Icono OpenAccess

Citations

173

Altmetrics

Grant support

This work was partially funded by Fundacion Mutua Madrilena and Fondo de Investigaciones Sanitarias (PIs: Esther Conde, Luis Paz-Ares and Fernando Lopez-Rios). DxS Limited provided some tests kits free of charge. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Analysis of institutional authors

Martinez, RAuthorRedondo, PAuthor

Share

August 4, 2021
Publications
>
Article
Sí

A Comparison of EGFR Mutation Testing Methods in Lung Carcinoma: Direct Sequencing, Real-time PCR and Immunohistochemistry

Publicated to:Plos One. 7 (8): - 2012-08-27 7(8), DOI: 10.1371/journal.pone.0043842

Authors: Angulo, B; Conde, E; Suarez-Gauthier, A; Plaza, C; Martinez, R; Redondo, P; Izquierdo, E; Rubio-Viqueira, B; Paz-Ares, L; Hidalgo, M; Lopez-Rios, F

Affiliations

Hosp Univ Virgen del Rocio, Seville, Spain - Author
Inst Biomed Sevilla IBIS, Dept Oncol, Seville, Spain - Author
Spanish Natl Canc Res Ctr, Gastrointestinal Canc Clin Res Unit, Madrid, Spain - Author
Univ San Pablo CEU, Hosp HM Univ Sanchinarro, Ctr Integral Oncol Clara Campal, Lab Dianas Terapeut,Fac Med, Madrid, Spain - Author

Abstract

The objective of this study is to compare two EGFR testing methodologies (a commercial real-time PCR kit and a specific EGFR mutant immunohistochemistry), with direct sequencing and to investigate the limit of detection (LOD) of both PCR-based methods. We identified EGFR mutations in 21 (16%) of the 136 tumours analyzed by direct sequencing. Interestingly, the Therascreen EGFR Mutation Test kit was able to characterize as wild-type one tumour that could not be analyzed by direct sequencing of the PCR product. We then compared the LOD of the kit and that of direct sequencing using the available mutant tumours. The kit was able to detect the presence of a mutation in a 1% dilution of the total DNA in nine of the 18 tumours (50%), which tested positive with the real-time quantitative PCR method. In all cases, EGFR mutation was identified at a dilution of 5%. Where the mutant DNA represented 30% of the total DNA, sequencing was able to detect mutations in 12 out of 19 cases (63%). Additional experiments with genetically defined standards (EGFR Delta E746-A750/+ and EGFR L858R/+) yielded similar results. Immunohistochemistry (IHC) staining with exon 19-specific antibody was seen in eight out of nine cases with E746-A750del detected by direct sequencing. Neither of the two tumours with complex deletions were positive. Of the five L858R-mutated tumours detected by the PCR methods, only two were positive for the exon 21-specific antibody. The specificity was 100% for both antibodies. The LOD of the real-time PCR method was lower than that of direct sequencing. The mutation specific IHC produced excellent specificity.

Keywords

AccuracyActivating mutationsAdultAgedAged, 80 and overAnalytic methodArticleBase sequenceCancerDirect sequencingDna mutational analysisEgfr geneEpidermal-growth-factorExonFactor-receptor mutationsFemaleGefitinib treatmentGene copy numberGene deletionGene expressionGene frequencyGene mutationHumanHuman tissueHumansImmunohistochemistryIntermethod comparisonLimit of detectionLung carcinomaLung neoplasmsMajor clinical studyMaleMiddle agedMutational analysisOncogenePersonalized medicinePoint mutationPolymerase-chain-reactionPredictive valueProtein expressionReal time polymerase chain reactionReal-time polymerase chain reactionReceptor, epidermal growth factorSensitivity and specificityTyrosine kinase inhibitors

Quality index

Bibliometric impact. Analysis of the contribution and dissemination channel

The work has been published in the journal Plos One due to its progression and the good impact it has achieved in recent years, according to the agency WoS (JCR), it has become a reference in its field. In the year of publication of the work, 2012, it was in position 7/56, thus managing to position itself as a Q1 (Primer Cuartil), in the category Multidisciplinary Sciences.

From a relative perspective, and based on the normalized impact indicator calculated from World Citations provided by WoS (ESI, Clarivate), it yields a value for the citation normalization relative to the expected citation rate of: 1.58. This indicates that, compared to works in the same discipline and in the same year of publication, it ranks as a work cited above average. (source consulted: ESI Nov 14, 2024)

This information is reinforced by other indicators of the same type, which, although dynamic over time and dependent on the set of average global citations at the time of their calculation, consistently position the work at some point among the top 50% most cited in its field:

  • Weighted Average of Normalized Impact by the Scopus agency: 4.65 (source consulted: FECYT Feb 2024)
  • Field Citation Ratio (FCR) from Dimensions: 17.4 (source consulted: Dimensions Jul 2025)

Specifically, and according to different indexing agencies, this work has accumulated citations as of 2025-07-09, the following number of citations:

  • WoS: 75
  • Scopus: 94

Impact and social visibility

From the perspective of influence or social adoption, and based on metrics associated with mentions and interactions provided by agencies specializing in calculating the so-called "Alternative or Social Metrics," we can highlight as of 2025-07-09:

  • The use, from an academic perspective evidenced by the Altmetric agency indicator referring to aggregations made by the personal bibliographic manager Mendeley, gives us a total of: 81.
  • The use of this contribution in bookmarks, code forks, additions to favorite lists for recurrent reading, as well as general views, indicates that someone is using the publication as a basis for their current work. This may be a notable indicator of future more formal and academic citations. This claim is supported by the result of the "Capture" indicator, which yields a total of: 81 (PlumX).

With a more dissemination-oriented intent and targeting more general audiences, we can observe other more global scores such as:

  • The Total Score from Altmetric: 3.
  • The number of mentions on Wikipedia: 1 (Altmetric).

It is essential to present evidence supporting full alignment with institutional principles and guidelines on Open Science and the Conservation and Dissemination of Intellectual Heritage. A clear example of this is:

  • The work has been submitted to a journal whose editorial policy allows open Open Access publication.

Leadership analysis of institutional authors

There is a significant leadership presence as some of the institution’s authors appear as the first or last signer, detailed as follows: First Author (Angulo, B) and Last Author (Lopez-Rios, F).

the authors responsible for correspondence tasks have been Angulo, B and Suarez-Gauthier, A.