1406P External quality assessment of immunohistochemistry, in-situ hybridization and RNA/DNA sequencing for ROS1 testing reveals high concordance for all methods

Estrogen receptor (ER), progesterone receptor (PgR), Ki-67, and HER2 immunohistochemistry (IHC) together with HER2 in situ hybridization (ISH) are utilized to classify invasive breast cancer (IBC) into predictive molecular subtypes. As IHC evaluation may be hampered by analytical errors, gene expression assays could offer a reliable alternative. In this first Europe-wide external quality assessment (EQA) study, we investigated performance of mRNA-based Xpert® Breast Cancer STRAT4 (CE-IVD) in five European laboratories. The cohort comprised ten pre-therapy IBC core biopsies diagnosed in the coordinating center (CC). STRAT4 binary (positive or negative) mRNA results of each marker (ESR1, PGR, ERBB2, MKI67) were compared with the gold standard IHC/ISH performed by the CC. Sensitivity, specificity, and accuracy of ESR1 and ERBB2 mRNA were 100% for all samples. In contrast, PGR expression was falsely negative for one case by two sites and MKI67 falsely negative for two cases (respectively by four and one sites). These cases had STRAT4 expression values close to assay cut-offs and immunohistochemically presented heterogeneous low positive PgR and heterogeneous Ki-67. Our EQA shows that STRAT4 mRNA assay may be a reproducible method to evaluate ER, PgR, HER2, and Ki-67 status. However, cases with expression values close to assay cut-offs should be carefully reviewed.

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External quality assurance of HER2 in situ hybridisation (ISH) testing - evaluation of the changes in the UK National External Quality Assessment Scheme (NEQAS) over 8 years and the reflection on participant performance

10.26226/morressier.596dfd55d462b80292386fae ◽

2017 ◽

Author(s):

Katherine Sheehan

Keyword(s):

Quality Assurance ◽

Quality Assessment ◽

External Quality Assessment ◽

In Situ Hybridisation ◽

External Quality Assurance ◽

External Quality ◽

External Quality Assessment Scheme ◽

The Uk

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Improvement of Technical and Analytical Performance in DNA Sequencing by External Quality Assessment-Based Molecular Training

Clinical Chemistry ◽

10.1373/clinchem.2006.072405 ◽

2006 ◽

Vol 52 (11) ◽

pp. 2072-2078 ◽

Cited By ~ 8

Author(s):

Alexandra Dorn-Beineke ◽

Parviz Ahmad-Nejad ◽

Ulrike Pfeiffer ◽

Simon Ramsden ◽

Mario Pazzagli ◽

...

Keyword(s):

Dna Sequencing ◽

Quality Assessment ◽

External Quality Assessment ◽

Substantial Improvement ◽

Data Sets ◽

The European Union ◽

External Quality ◽

Training Course ◽

Technical Performance ◽

Training Courses

Abstract Background: From 2003 to 2005, the European Union supported the EQUAL-initiative to develop methodological external quality assessment (EQA) schemes for genotyping (EQUALqual), quantitative PCR (EQUALquant), and sequencing (EQUALseq). As a relevant part of the EQUALseq program, a training course was held subsequent to the first EQA Program (EQAP1). The success of this course was reassessed in a 2nd EQUALseq round (EQAP2). Methods: In September 2005, a 3-day training course took place. We invited 8 laboratories with below-average performance in EQAP1 to improve their methodological and analytical/proficiency skills by lectures and practical work. To compare the results of the pretraining and posttraining EQUALseq rounds, we distributed 2 samples used in the first EQUAL round, but this time we provided different oligonucleotide sets. We evaluated the results by means of a previously described scoring system. Results: In EQAP2, 6 laboratories returned complete data sets, corresponding to an overall 14% of the 43 laboratories that had finished EQAP1. The scoring results for samples A (P = 0.0025) and B (P = 0.0125) demonstrated a significant improvement in EQAP2. Overall, a substantial improvement of technical and interpretative skills was demonstrated (P = 0.0051). In general, the workshop experience was highly rated by the participants. Conclusions: Methodologic EQAPs in DNA sequencing are appropriate tools to uncover strengths and weaknesses in both technique and proficiency, emphasizing the need for mandatory EQAPs. Training courses, together with 2nd-round reiterations, should be implemented into methodological EQAPs in molecular diagnostics to improve technical performance and proficiency in genetic testing.

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Benchmark for Evaluating the Quality of DNA Sequencing: Proposal from an International External Quality Assessment Scheme

Clinical Chemistry ◽

10.1373/clinchem.2005.061887 ◽

2006 ◽

Vol 52 (4) ◽

pp. 728-736 ◽

Cited By ~ 29

Author(s):

Simon J Patton ◽

Andrew J Wallace ◽

Rob Elles

Keyword(s):

Dna Sequencing ◽

Quality Assessment ◽

Clinical Laboratory ◽

External Quality Assessment ◽

Sequence Data ◽

False Negative ◽

Read Length ◽

External Quality ◽

External Quality Assessment Scheme

Abstract Background: In the past 15 years, clinical laboratory science has been transformed by the use of technologies that cross the traditional boundaries between laboratory disciplines. However, during this period, issues of quality have not always been given adequate attention. The European Molecular Genetics Quality Network (EMQN) has developed a novel external quality assessment scheme for evaluation of DNA sequencing. We report the results of an international survey of the quality of DNA sequencing among 64 laboratories from 21 countries. Methods: Current practice for DNA sequence analysis was established by use of an online questionnaire. Participating laboratories were provided with 4 DNA samples of validated genotype. Evaluation of the results included assessing the quality of sequence data, variant genotypes, and mutation nomenclature. To accommodate variations in mutation nomenclature, variants indicated by participants were scored for compliance with 3 acceptable marking schemes. Results: A total of 346 genotypes were analyzed. Of these, 19 (5%) genotyping errors were made. Of these, 10 (53%) were false-negative and 9 (47%) were false-positive results. A further 27 (8%) errors were made in naming mutations. Results were analyzed for 3 indicators of data quality: PHRED quality scores, Quality Read Length, and Quality Read Overlap. Most laboratories produced results of acceptable diagnostic quality as judged by these indicators. The results were used to calculate a consensus benchmark for DNA sequencing against which individual laboratories could rank their performance. Conclusions: We propose that the consensus benchmark can be used as a baseline against which the aggregate and individual laboratory standard of DNA sequencing may be tracked from year to year.

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