Arja Ter Elst

Dr. Arja Ter Elst


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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13 May 2020 in Cancers
Verified
Journal Article
Open access
PDF file
PLPaul van der Leest
Paul van der Leest
PBPieter Boonstra
Pieter Boonstra
AEArja Ter Elst
Arja Ter Elst
LKLéon van Kempen
Léon van Kempen
MTMarco Tibbesma
Marco Tibbesma
Ed SchuuringEd Schuuring
Ed Schuuring
Circulating cell-free DNA (ccfDNA) may contain DNA originating from the tumor in plasma of cancer patients (ctDNA) and enables noninvasive cancer diagnosis, treatment predictive testing, and response monitoring. A recent multicenter evaluation of workflows by the CANCER-ID consortium using artificial spiked-in plasma showed significant differences and consequently the importance of carefully selecting ccfDNA extraction methods. Here, the quantity and integrity of extracted ccfDNA from the plasma of cancer patients were assessed. Twenty-one cancer patient-derived cell-free plasma samples were selected to compare the Qiagen CNA, Maxwell RSC ccfDNA plasma, and Zymo manual quick ccfDNA kit. High-volume citrate plasma samples collected by diagnostic leukapheresis from six cancer patients were used to compare the Qiagen CNA (2 mL) and QIAamp MinElute ccfDNA kit (8 mL). This study revealed similar integrity and similar levels of amplified short-sized fragments and tumor-specific mutants comparing the CNA and RSC kits. However, the CNA kit consistently showed the highest yield of ccfDNA and short-sized fragments, while the RSC and ME kits showed higher variant allelic frequencies (VAFs). Our study pinpoints the importance of standardizing preanalytical conditions as well as consensus on defining the input of ccfDNA to accurately detect ctDNA and be able to compare results in a clinical routine practice, within and between clinical studies.

26 April 2024 in Cancers
Verified
Journal Article
Open access
PDF file
LLLieke Lanjouw
Lieke Lanjouw
JBJoost Bart
Joost Bart
Marian J MouritsMarian J Mourits
Marian J Mourits
SWStefan M. Willems
Stefan M. Willems
AHAnnemieke H. van der Hout
Annemieke H. van der Hout
GBGeertruida de Bock
Geertruida de Bock
Analyzing BRCA1/2 tumor pathogenic variants (TPVs) in epithelial tubal/ovarian cancers (EOCs) has become an essential part of the diagnostic workflow in many centers to guide treatment options and genetic cascade testing. However, there is no standardization of testing procedures, including techniques, gene assays, or sequencers used, and data on the execution of tumor tests remains scarce. Therefore, we evaluated characteristics of BRCA1/2 tumor testing in advanced-stage EOC with real-world national data. Pathology reports of patients diagnosed with EOC in 2019 in the Netherlands were obtained from the Dutch Pathology Registry (PALGA), and data regarding histological subtype and BRCA1/2 tumor tests were extracted. A total of 999 patients with advanced-stage EOC were included. Tumor tests were performed for 502 patients (50.2%) and BRCA1/2 TPVs were detected in 14.7%. Of all tests, 48.6% used hybrid capture techniques and 26.5% used PCR-based techniques. More than half of the tests (55.0%) analyzed other genes in addition to BRCA1/2. Overall, this study highlights the heterogeneity in the execution of BRCA1/2 tumor tests. Despite a lack of evidence of quality differences, we emphasize that adequate reporting and internal and external quality monitors are essential for the high-quality implementation and execution of reliable BRCA1/2 tumor testing, which is crucial for identifying all patients with BRCA1/2 TPVs.

12 August 2015 in Experimental Hematology & Oncology
Verified
Journal Article
Open access
PDF file
NSNaomi E van der Sligte
Naomi E van der Sligte
FSFrank Scherpen
Frank Scherpen
AEArja Ter Elst
Arja Ter Elst
VGVictor Guryev
Victor Guryev
FLFrank N van Leeuwen
Frank N van Leeuwen
EBEveline S J M de Bont
Eveline S J M de Bont
IKZF1 deletions are an unfavorable prognostic factor in children with Philadelphia chromosome positive (Ph + ) as well as negative (Ph − ) acute lymphoblastic leukemia (ALL). Although IKZF1 deletions occur in 10–15% of Ph − ALL cases, effects of IKZF1 deletions on signaling pathways in this group have not been extensively studied. Therefore, in this study we aimed to study the effect of IKZF1 deletions on active signal transduction pathways.

5 May 2025 in Familial Cancer
Verified
Journal Article
Open access
PDF file
LLLieke Lanjouw
Lieke Lanjouw
CKClaire Kramer
Claire Kramer
AEArja Ter Elst
Arja Ter Elst
GBGeertruida de Bock
Geertruida de Bock
KGKatja Gaarenstroom
Katja Gaarenstroom
JBJoost Bart
Joost Bart
Identification of somatic and germline BRCA1/2 pathogenic variants in epithelial ovarian cancer (EOC) patients is essential for determining poly-(ADP-ribose)-polymerase (PARP) inhibitor sensitivity and genetic predisposition. In the Netherlands, BRCA1/2 testing changed to a tumor-first approach to efficiently identify both somatic and germline pathogenic variants in all patients. Here, we performed an in-depth evaluation of the first four years of the tumor-first test-pathway. Data of consecutive series of patients diagnosed with EOC in two regions were obtained from the Netherlands Cancer Registry. Tumor and/or germline test data were retrieved from hospital databases. The primary outcome was the percentage of patients completing the BRCA1/2 test-pathway, defined as having a negative tumor test or a referral for a germline test in case of a positive tumor test or no tumor test. Factors associated with test-pathway completion were identified through multivariable logistic regression analysis. In total, 69.8% (757/1085) completed the test-pathway. This was 74.4% in the most recent year. Younger patients, patients diagnosed in year three or four, patients with high-grade serous/high-grade endometrioid carcinoma, advanced stage disease, middle or high socioeconomic status, and patients who underwent surgery or chemotherapy, were more likely to complete the test-pathway. We report inequalities in genetic testing access in EOC patients, which highlight the need for better guideline adherence, particularly in older patients, those with low socioeconomic status, low-grade histotypes, early-stage disease and those without surgery or chemotherapy. Additionally, timely testing of patients, and testing relatives if patients cannot be tested, are crucial to increase test uptake.

9 April 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
LLLieke Lanjouw
Lieke Lanjouw
JBJoost Bart
Joost Bart
Marian J MouritsMarian J Mourits
Marian J Mourits
SWStefan M. Willems
Stefan M. Willems
AHAnnemieke H. van der Hout
Annemieke H. van der Hout
GBGeertruida de Bock
Geertruida de Bock
Analyzing BRCA1/2 tumor pathogenic variants (TPVs) in epithelial tubal/ovarian cancers (EOC) has become an essential part of the diagnostic workflow in many centers to guide treatment options and genetic cascade testing. However, there is no standardization of testing procedures, including techniques, gene assays, or sequencers used, and data on the execution of tumor tests remains scarce. Therefore, we evaluated characteristics of BRCA1/2 tumor testing in advanced-stage EOC with real-world national data. Pathology reports of patients diagnosed with EOC in 2019 in the Netherlands were obtained from the Dutch Pathology Registry (PALGA), and data regarding histological subtype and BRCA1/2 tumor tests were extracted. A total of 999 patients with advanced-stage EOC were included. Tumor tests were performed for 502 patients (50.2%) and BRCA1/2 TPVs were detected in 14.7%. Of all tests, 48.6% used hybrid capture techniques and 26.5% used PCR-based techniques. More than half of the tests (55.0%) analyzed other genes in addition to BRCA1/2. Overall, this study highlights the heterogeneity in the execution of BRCA1/2 tumor tests. Despite a lack of evidence of quality differences, we emphasize that adequate reporting and internal and external quality monitors are essential for high-quality implementation and execution of reliable BRCA1/2 tumor testing, which is crucial for identifying all patients with BRCA1/2 TPVs.