scholarly journals External quality assessment (EQA) program for the immunohistochemical detection of ER, PR and Ki-67 in breast cancer: results of an interlaboratory reproducibility ring study in China

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Tianjie Pu ◽  
◽  
Ruohong Shui ◽  
Jie Shi ◽  
Zhiyong Liang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Quality Assessment ◽  
External Quality Assessment ◽  
Reference Value ◽  
Evaluation Process ◽  
Daily Practice ◽  
External Quality ◽  
Ki 67 ◽  
Perfect Agreement ◽  
Misclassification Rates

Abstract Background An External Quality Assessment (EQA) program was developed to investigate the status of estrogen receptor (ER), progesterone receptor (PR), and Ki-67 immunohistochemical (IHC) detection in breast cancer and to evaluate the reproducibility of staining and interpretation in 44 pathology laboratories in China. Methods This program was implemented through three specific steps. In study I, three revising centres defined the reference value for 11 sections. In study II, 41 participating centres (PC) stained and interpreted 11 sections by their own daily practice IHC protocols. In study III, all cases received second interpretation opinions. Results The stained slides of 44 laboratories were up to the interpretation standard. The overall interpretation concordance rate of this study was over 90%. A perfect agreement was reached among the PCs for the cases with ER+ and PR+ > 50% and Ki-67 > 30%, whereas a moderate agreement was observed for intermediate categories. After second interpretations, the misclassification rates for ER were reduced by 12.20%, for PR were reduced by 17.07%, and for Ki-67 were reduced by 4.88%. Up to 31 PCs observed a benefit from the second opinion strategy. Conclusions This project is the first EQA study performed on a national scale for assessment of ER, PR and Ki-67 status by IHC in China. In the whole IHC evaluation process, the intermediate categories were less reproducible than those with high expression rates. Second opinions can significantly improve the diagnostic agreement of pathologists’ interpretations.

scholarly journals Reproducibility of mRNA-Based Testing of ESR1, PGR, ERBB2, and MKI67 Expression in Invasive Breast Cancer—A Europe-Wide External Quality Assessment

Cancers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 4718
Author(s):  
Ramona Erber ◽  
Arndt Hartmann ◽  
Peter Andreas Fasching ◽  
Matthias Ruebner ◽  
Robert Stöhr ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Quality Assessment ◽  
Invasive Breast Cancer ◽  
External Quality Assessment ◽  
External Quality ◽  
Ki 67 ◽  
Erbb2 Mrna ◽  
Reproducible Method ◽  
Sensitivity Specificity

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.

scholarly journals Application of the Characteristic Function to Evaluate and Compare Analytical Variability in an External Quality Assessment Scheme for Serum Ethanol

2015 ◽  
Vol 61 (7) ◽  
pp. 948-954 ◽  
Author(s):  
Wim Coucke ◽  
Corine Charlier ◽  
Willy Lambert ◽  
Frank Martens ◽  
Hugo Neels ◽  
...  
Keyword(s):  
Characteristic Function ◽  
Quality Assessment ◽  
Analytical Methods ◽  
External Quality Assessment ◽  
Evaluation Process ◽  
Clinical Diagnostics ◽  
External Quality ◽  
Target Concentration ◽  
External Quality Assessment Scheme ◽  
Method Performance

Abstract BACKGROUND As a cornerstone of quality management in the laboratory, External Quality Assessment (EQA) schemes are used to assess laboratory and analytical method performance. The characteristic function is used to describe the relation between the target concentration and the EQA standard deviation, which is an essential part of the evaluation process. The characteristic function is also used to compare the variability of different analytical methods. METHODS We fitted the characteristic function to data from the Belgian External Quality Assessment program for serum ethanol. Data included results from headspace gas chromatography and the enzymatic methods of Abbott, Roche, Siemens, and Ortho-Clinical Diagnostics. We estimated the characteristic function with weighted nonlinear regression. By introducing dummy variables, we rewrote the original formula of the characteristic function to assess statistical inference for comparing the variability of the different analytical methods. RESULTS The characteristic function fitted the data precisely. Comparison between methods showed that there was little difference between the estimated variability for low concentrations, and that the increase in SD with increasing target concentration was slower for Abbott and Roche than for the other methods. CONCLUSIONS The characteristic function can successfully be introduced in clinical schemes, although its applicability to fit the data should always be assessed. Because of its easy parameterization, it can be used to assess differences in performance between analytical methods and to assess laboratory performance. The characteristic function also offers an alternative framework for coefficients of variation to describe variability of analytical methods.

scholarly journals 28P Europe-side external quality assessment (EQA) of RNA based testing of ER, PR, HER2 and Ki67 in invasive breast cancer

2020 ◽  
Vol 31 ◽  
pp. S25
Author(s):  
R. Erber ◽  
A. Hartmann ◽  
P. Fasching ◽  
R. Stöhr ◽  
M.W. Beckmann ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Quality Assessment ◽  
Invasive Breast Cancer ◽  
External Quality Assessment ◽  
External Quality

scholarly journals The versatility of external quality assessment for the surveillance of laboratory and in vitro diagnostic performance: SARS-CoV-2 viral genome detection in Austria

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christoph Buchta ◽  
Jeremy V. Camp ◽  
Jovana Jovanovic ◽  
Peter Chiba ◽  
Elisabeth Puchhammer-Stöckl ◽  
...  
Keyword(s):  
Quality Assessment ◽  
External Quality Assessment ◽  
False Negative ◽  
Positive Sample ◽  
Performance Criteria ◽  
External Quality ◽  
Assay Sensitivity ◽  
Dilution Series ◽  
Test Systems

Abstract Objectives External quality assessment (EQA) schemes provide information on individual and general analytical performance of participating laboratories and test systems. The aim of this study was to investigate the use and performance of SARS-CoV-2 virus genome detection systems in Austrian laboratories and their preparedness to face challenges associated with the pandemic. Methods Seven samples were selected to evaluate performance and estimate variability of reported results. Notably, a dilution series was included in the panel as a measure of reproducibility and sensitivity. Several performance criteria were evaluated for individual participants as well as in the cohort of all participants. Results A total of 109 laboratories participated and used 134 platforms, including 67 different combinations of extraction and PCR platforms and corresponding reagents. There were no false positives and 10 (1.2%) false negative results, including nine in the weakly positive sample (C t ∼35.9, ∼640 copies/mL). Twenty (22%) laboratories reported results of mutation detection. Twenty-five (19%) test systems included amplification of human RNA as evidence of proper sampling. The overall linearity of C t values from individual test systems for the dilution series was good, but inter-assay variability was high. Both operator-related and systematic failures appear to have caused incorrect results. Conclusions Beyond providing certification for participating laboratories, EQA provides the opportunity for participants to evaluate their performance against others so that they may improve operating procedures and test systems. Well-selected EQA samples offer additional inferences to be made about assay sensitivity and reproducibility, which have practical applications.

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