Elisabeth MC Dequeker

Prof. Dr. Elisabeth MC Dequeker

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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26 March 2011 in The Oncologist
Verified
Journal Article
Closed access
EBEllen Bellon
Ellen Bellon
MLMarjolijn J.L. Ligtenberg
Marjolijn J.L. Ligtenberg
STSabine Tejpar
Sabine Tejpar
KCKaren Cox
Karen Cox
GHGert Hertogh
Gert Hertogh
EDElisabeth MC Dequeker
Elisabeth MC Dequeker
Learning Objectives: After completing this course, the reader will be able to: Identify the most frequent errors made in KRAS testing in this study and the possible consequences for a patient.Describe factors that could increase the chance of an error during KRAS testing. This article is available for continuing medical education credit at CME.TheOncologist.com The use of epidermal growth factor receptor–targeting antibodies in metastatic colorectal cancer has been restricted to patients with wild-type KRAS tumors by the European Medicines Agency since 2008, based on data showing a lack of efficacy and potential harm in patients with mutant KRAS tumors. In an effort to ensure optimal, uniform, and reliable community-based KRAS testing throughout Europe, a KRAS external quality assessment (EQA) scheme was set up. The first large assessment round included 59 laboratories from eight different European countries. For each country, one regional scheme organizer prepared and distributed the samples for the participants of their own country. The samples included unstained sections of 10 invasive colorectal carcinomas with known KRAS mutation status. The samples were centrally validated by one of two reference laboratories. The laboratories were allowed to use their own preferred method for histological evaluation, DNA isolation, and mutation analysis. In this study, we analyze the setup of the KRAS scheme. We analyzed the advantages and disadvantages of the regional scheme organization by analyzing the outcome of genotyping results, analysis of tumor percentage, and written reports. We conclude that only 70% of laboratories correctly identified the KRAS mutational status in all samples. Both the false-positive and false-negative results observed negatively affect patient care. Reports of the KRAS test results often lacked essential information. We aim to further expand this program to more laboratories to provide a robust estimate of the quality of KRAS testing in Europe, and provide the basis for remedial measures and harmonization.

1 April 2022 in European Journal of Human Genetics
Verified
Journal Article
Open access
PDF file
ZDZandra C. Deans
Zandra C. Deans
JAJoo Wook Ahn
Joo Wook Ahn
ICIsabel M. Carreira
Isabel M. Carreira
EDElisabeth MC Dequeker
Elisabeth MC Dequeker
MHMick Henderson
Mick Henderson
CAChristi J. van Asperen
Christi J. van Asperen
Results of clinical genomic testing must be reported in a clear, concise format to ensure they are understandable and interpretable. It is important laboratories are aware of the information which is essential to make sure the results are not open to misinterpretation. As genomic testing has continued to evolve over the past decade, the European Society of Human Genetics (ESHG) recommendations for reporting results of diagnostic genetic testing (biochemical, cytogenetic and molecular genetic) published in 2014 have been reviewed and updated to provide the genomic community with guidance on reporting unambiguous results.

9 August 2018 in BMC Cancer
Verified
Journal Article
Open access
PDF file
CKCleo Keppens
Cleo Keppens
EDElisabeth MC Dequeker
Elisabeth MC Dequeker
SPSimon J. Patton
Simon J. Patton
NNNicola Normanno
Nicola Normanno
FFFrancesca Fenizia
Francesca Fenizia
ZDZandra C. Deans
Zandra C. Deans
Molecular analysis of circulating tumour DNA (ctDNA) is becoming increasingly important in clinical treatment decisions. A pilot External Quality Assessment (EQA) scheme for ctDNA analysis was organized by four European EQA providers under the umbrella organization IQN Path, in order to investigate the feasibility of delivering an EQA to assess the detection of clinically relevant variants in plasma circulating cell-free DNA (cfDNA) and to analyze reporting formats. Thirty-two experienced laboratories received 5 samples for EGFR mutation analysis and/or 5 samples for KRAS and NRAS mutation analysis. Samples were artificially manufactured to contain 3 mL of human plasma with 20 ng/mL of fragmented ctDNA and variants at allelic frequencies of 1 and 5%. The scheme error rate was 20.1%. Higher error rates were observed for RAS testing when compared to EGFR analysis, for allelic frequencies of 1% compared to 5%, and for cases including 2 different variants. The reports over-interpreted wild-type results and frequently failed to comment on the amount of cfDNA extracted. The pilot scheme demonstrated the feasibility of delivering a ctDNA EQA scheme and the need for such a scheme due to high error rates in detecting low frequency clinically relevant variants. Recommendations to improve reporting of cfDNA are provided.

1 July 2018 in The Journal of Molecular Diagnostics
Verified
Journal Article
Closed access
CKCleo Keppens
Cleo Keppens
JPJohn Palma
John Palma
PDPartha M. Das
Partha M. Das
SSSidney Scudder
Sidney Scudder
WWWei Wen
Wei Wen
EDElisabeth MC Dequeker
Elisabeth MC Dequeker

28 July 2022 in Cancers
Verified
Journal Article
Open access
PDF file
NLNele Laudus
Nele Laudus
LNLynn Nijs
Lynn Nijs
INInne Nauwelaers
Inne Nauwelaers
EDElisabeth MC Dequeker
Elisabeth MC Dequeker
External quality assessment (EQA) schemes are a tool for clinical laboratories to evaluate and manage the quality of laboratory practice with the support of an independent party (i.e., an EQA provider). Depending on the context, there are different types of EQA schemes available, as well as various EQA providers, each with its own field of expertise. In this review, an overview of the general requirements for EQA schemes and EQA providers based on international guidelines is provided. The clinical and scientific value of these kinds of schemes for clinical laboratories, clinicians and patients are highlighted, in addition to the support EQA can provide to other types of laboratories, e.g., laboratories affiliated to biotech companies. Finally, recent developments and challenges in laboratory medicine and quality management, for example, the introduction of artificial intelligence in the laboratory and the shift to a more individual-approach instead of a laboratory-focused approach, are discussed. EQA schemes should represent current laboratory practice as much as possible, which poses the need for EQA providers to introduce latest laboratory innovations in their schemes and to apply up-to-date guidelines. By incorporating these state-of-the-art techniques, EQA aims to contribute to continuous learning.

5 February 2015 in The Oncologist
Verified
Journal Article
Open access
PDF file
VTVéronique Tack
Véronique Tack
MLMarjolijn J.L. Ligtenberg
Marjolijn J.L. Ligtenberg
LTLien Tembuyser
Lien Tembuyser
NNNicola Normanno
Nicola Normanno
SBSara Vander Borght
Sara Vander Borght
EDElisabeth MC Dequeker
Elisabeth MC Dequeker
Background.: Regulations for the selection of patients with metastatic colorectal cancer for anti-EGFR treatment changed at the end of 2013. The set of mutations to be tested extended from KRAS codons 12 and 13 to KRAS and NRAS exons 2, 3, and 4. A European external quality assessment scheme monitored the performance of laboratories and evaluated the implementation of the new regulations. Materials and Methods.: The 131 participating laboratories received 10 samples of formalin-fixed paraffin-embedded material, including RAS (exon 2, 3, 4) and BRAF mutations. Mock clinical data were provided for three cases. Using their routine methods, laboratories determined the genotypes and submitted three written reports. Assessors scored the results according to predefined evaluation criteria. Results.: Half of the participants (49.3%) had completely implemented the new test requirements (codons 12, 13, 59, 61, 117, and 146 of KRAS and NRAS), and 96 laboratories (73.3%) made no genotype mistakes. Correct nomenclature, according to the Human Genome Variation Society, was used by 82 laboratories (62.6%). Conclusion.: Although regulations were effective for several months, many laboratories were not ready for full RAS testing in the context of anti-EGFR therapy. Nevertheless, in each participating country, there are laboratories that provide complete and correct testing. External quality assessments can be used to monitor implementation of new test regulations and to stimulate the laboratories to improve their testing procedures. Because the results of this program are available on the website of the European Society of Pathology, patients and clinicians can refer test samples to a reliable laboratory.