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Trapé J, Bérgamo S, González-Fernández C, Rives J, González-García L. Variations in tumor growth, intra-individual biological variability, and the interpretation of changes. Clin Chem Lab Med 2024; 62:1618-1625. [PMID: 38369758 DOI: 10.1515/cclm-2023-0780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 02/02/2024] [Indexed: 02/20/2024]
Abstract
OBJECTIVES The identification of changes in tumor markers (TMs) in cancer patients that indicate response to treatment, stabilization or disease progression is a challenge for laboratory medicine. Several approaches have been proposed: assessing percentage increases, applying discriminant values, and estimating half-life (t1/2) or doubling time (DT). In all of them it is assumed that the TM is a surrogate of the variation in tumor size. In general this variation is time-dependent, but this is not the case of intraindividual biological variability (CVi), which can range from 6 % in CA15-3 to 22 % in CA125. When decisions are made on the basis of DT or t1/2, these values can be affected by the CVi; if it is very large, the growth rate very slow and the period of time between determinations very short, the result obtained for DT may be due mainly to the CVi. The aim of this study is to establish the relationship between the CVi and temporal variables. METHODS We related equations for calculating DT and t1/2 to the reference change values in tumor markers. RESULTS The application of the formula obtained allows the calculation of the optimal time between measurements to ensure that the influence of the CVi is minimal in different types of tumors and different scenarios. CONCLUSIONS Intraindividual variation affects the calculation of DT and t1/2. It is necessary to establish the minimum time between two measurements to ensure that the CVi does not affect their calculation or lead to misinterpretation.
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Affiliation(s)
- Jaume Trapé
- Laboratory Medicine Department, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Catalonia, Spain
- Tissue Repair and Regeneration Laboratory (TR2Lab), Centre for Health and Social Care Research (CESS), University of Vic - Central University of Catalonia, Institut de Recerca i Innovació en Ciències de la Vida i de la Salut a la Catalunya Central (IRIS-CC), Vic, Spain
- Faculty of Medicine, University of Vic - Central University of Catalonia, Vic, Spain
| | - Silvia Bérgamo
- Laboratory Medicine Department, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Catalonia, Spain
- Tissue Repair and Regeneration Laboratory (TR2Lab), Centre for Health and Social Care Research (CESS), University of Vic - Central University of Catalonia, Institut de Recerca i Innovació en Ciències de la Vida i de la Salut a la Catalunya Central (IRIS-CC), Vic, Spain
- Doctoral School, University of Vic - Central University of Catalonia, Vic, Spain
| | - Carolina González-Fernández
- Laboratory Medicine Department, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Catalonia, Spain
- Gastrointestinal Oncology, Endoscopy and Surgery research group (GOES), Institut de Recerca i Innovació en Ciències de la Vida i de la Salut a la Catalunya Central (IRIS-CC), Vic, Spain
| | - José Rives
- Laboratory Medicine Department, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Catalonia, Spain
| | - Laura González-García
- Laboratory Medicine Department, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Catalonia, Spain
- Tissue Repair and Regeneration Laboratory (TR2Lab), Centre for Health and Social Care Research (CESS), University of Vic - Central University of Catalonia, Institut de Recerca i Innovació en Ciències de la Vida i de la Salut a la Catalunya Central (IRIS-CC), Vic, Spain
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van Rossum HH, Holdenrieder S, Ballieux BEPB, Badrick TC, Yun YM, Zhang C, Patel D, Thelen M, Song J, Wojtalewicz N, Unsworth N, Vesper HW, Cui W, Ramanathan LV, Sturgeon C, Meng QH. Investigating the Current Harmonization Status of Tumor Markers Using Global External Quality Assessment Programs: A Feasibility Study. Clin Chem 2024; 70:669-679. [PMID: 38385453 DOI: 10.1093/clinchem/hvae005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 12/11/2023] [Indexed: 02/23/2024]
Abstract
BACKGROUND The harmonization status of most tumor markers (TMs) is unknown. We report a feasibility study performed to determine whether external quality assessment (EQA) programs can be used to obtain insights into the current harmonization status of the tumor markers α-fetoprotein (AFP), prostate specific antigen (PSA), carcinoembryonic antigen (CEA), cancer antigen (CA)125, CA15-3 and CA19-9. METHODS EQA sample results provided by 6 EQA providers (INSTAND [Germany], Korean Association of External Quality Assessment Service [KEQAS, South Korea], National Center for Clinical Laboratories [NCCL, China], United Kingdom National External Quality Assessment Service [UK NEQAS, United Kingdom], Stichting Kwaliteitsbewaking Medische Laboratoriumdiagnostiek [SKML, the Netherlands], and the Royal College of Pathologists of Australasia Quality Assurance Programs [RCPAQAP, Australia]) between 2020 and 2021 were used. The consensus means, calculated from the measurement procedures present in all EQA programs (Abbott Alinity, Beckman Coulter DxI, Roche Cobas, and Siemens Atellica), was used as reference values. Per measurement procedure, the relative difference between consensus mean for each EQA sample and the mean of all patient-pool-based EQA samples were calculated and compared to minimum, desirable, and optimal allowable bias criteria based on biological variation. RESULTS Between 19040 (CA15-3) and 25398 (PSA) individual results and 56 (PSA) to 76 (AFP) unique EQA samples were included in the final analysis. The mean differences with the consensus mean of patient-pool-based EQA samples for all measurement procedures were within the optimum bias criterion for AFP, the desirable bias for PSA, and the minimum bias criterion for CEA. However, CEA results <8 µg/L exceeded the minimum bias criterion. For CA125, CA15-3, and CA19-9, the harmonization status was outside the minimum bias criterion, with systematic differences identified. CONCLUSIONS This study provides relevant information about the current harmonization status of 6 tumor markers. A pilot harmonization investigation for CEA, CA125, CA15-3, and CA19-9 would be desirable.
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Affiliation(s)
- Huub H van Rossum
- Department of Laboratory Medicine, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Stefan Holdenrieder
- Institute of Laboratory Medicine, Munich Biomarker Research Center, Deutsches Herzzentrum München, Technische Universität München, Munich, Germany
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Duesseldorf, Germany
| | - Bart E P B Ballieux
- Department of Clinical Chemistry, Leiden University Medical Center, Leiden, the Netherlands
| | - Tony C Badrick
- RCPA Quality Assurance Programs, St Leonards, Sydney, Australia
| | - Yeo-Min Yun
- Department of Laboratory Medicine, Konkuk University Medical Center, Seoul, South Korea
| | - Chuanbao Zhang
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology, Beijing, China
| | - Dina Patel
- UK NEQAS Immunology, Immunochemistry & Allergy, Northern General Hospital, Sheffield, United Kingdom
| | - Marc Thelen
- SKML, Nijmegen, the Netherlands
- Department of Laboratory Medicine of the Radboud University Medical Center, Nijmegen, the Netherlands
| | - Junghan Song
- Department of Laboratory Medicine, Seoul National University Bundang Hospital and College of Medicine, Seongnam, South Korea
| | - Nathalie Wojtalewicz
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Duesseldorf, Germany
| | - Nick Unsworth
- UK NEQAS [Edinburgh], Department of Laboratory Medicine, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Hubert W Vesper
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Wei Cui
- Department of Laboratory Medicine, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Lakshmi V Ramanathan
- Clinical Chemistry Service, Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Catharine Sturgeon
- UK NEQAS [Edinburgh], Department of Laboratory Medicine, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Qing H Meng
- Department of Laboratory Medicine, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
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Coskun A, Lippi G. The impact of physiological variations on personalized reference intervals and decision limits: an in-depth analysis. Clin Chem Lab Med 2024; 0:cclm-2024-0009. [PMID: 38452477 DOI: 10.1515/cclm-2024-0009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 02/27/2024] [Indexed: 03/09/2024]
Abstract
The interpretation of laboratory data is a comparative procedure. Physicians typically need reference values to compare patients' laboratory data for clinical decisions. Therefore, establishing reliable reference data is essential for accurate diagnosis and patient monitoring. Human metabolism is a dynamic process. Various types of systematic and random fluctuations in the concentration/activity of biomolecules are observed in response to internal and external factors. In the human body, several biomolecules are under the influence of physiological rhythms and are therefore subject to ultradian, circadian and infradian fluctuations. In addition, most biomolecules are also characterized by random biological variations, which are referred to as biological fluctuations between subjects and within subjects/individuals. In routine practice, reference intervals based on population data are used, which by nature are not designed to capture physiological rhythms and random biological variations. To ensure safe and appropriate interpretation of patient laboratory data, reference intervals should be personalized and estimated using individual data in accordance with systematic and random variations. In this opinion paper, we outline (i) the main variations that contribute to the generation of personalized reference intervals (prRIs), (ii) the theoretical background of prRIs and (iii) propose new methods on how to harmonize prRIs with the systematic and random variations observed in metabolic activity, based on individuals' demography.
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Affiliation(s)
- Abdurrahman Coskun
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Türkiye
| | - Giuseppe Lippi
- Section of Clinical Biochemistry, 19051 University of Verona , Verona, Italy
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Canki E, Schuurbiers MM, Linders TC, Korse CM, van den Heuvel MM, van Herwaarden AE, van Rossum HH. Pre-analytical stability of the CEA, CYFRA 21.1, NSE, CA125 and HE4 tumor markers. Tumour Biol 2024; 46:S15-S25. [PMID: 37302060 DOI: 10.3233/tub-220013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023] Open
Abstract
BACKGROUND For lung cancer, circulating tumor markers (TM) are available to guide clinical treatment decisions. To ensure adequate accuracy, pre-analytical instabilities need to be known and addressed in the pre-analytical laboratory protocols. OBJECTIVE This study investigates the pre-analytical stability of CA125, CEA, CYFRA 21.1, HE4 and NSE for the following pre-analytical variables and procedures; i) whole blood stability, ii) serum freeze-thaw cycles, iii) electric vibration mixing and iv) serum storage at different temperatures. METHODS Left-over patient samples were used and for every investigated variable six patient samples were used and analysed in duplicate. Acceptance criteria were based on analytical performance specifications based on biological variation and significant differences with baseline. RESULTS Whole blood was stable for at least 6 hours for all TM except for NSE. Two freeze-thaw cycles were acceptable for all TM except CYFRA 21.1. Electric vibration mixing was allowed for all TM except for CYFRA 21.1. Serum stability at 4°C was 7 days for CEA, CA125, CYFRA 21.1 and HE4 and 4 hours for NSE. CONCLUSIONS Critical pre-analytical processing step conditions were identified that, if not taken into account, will result in reporting of erroneous TM results.
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Affiliation(s)
- Esra Canki
- Department of Laboratory Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
- Department of Respiratory Diseases, Radboud Medical Center, Nijmegen, The Netherlands
| | - Milou Mf Schuurbiers
- Department of Respiratory Diseases, Radboud Medical Center, Nijmegen, The Netherlands
| | - Theodora C Linders
- Department of Laboratory Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Catharina M Korse
- Department of Laboratory Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | | | | | - Huub H van Rossum
- Department of Laboratory Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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van Rossum HH, Holdenrieder S. Lung cancer tumor marker analysis: A clinical laboratory perspective. Tumour Biol 2024; 46:S9-S14. [PMID: 38517828 DOI: 10.3233/tub-240005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2024] Open
Abstract
Clinical laboratories are responsible for performing lung cancer tumor marker testing as part of routine clinical care. It is their responsibility to guarantee that the reported tumor marker results are reliable and meet the necessary quality standards for proper clinical use. During the different laboratory phases, pre-analytical, analytical and post-analytical, specific steps and processes can introduce errors and generate incorrect clinical interpretation. This editorial briefly outlines critical laboratory issues related to lung cancer tumor markers, specific for each of these three laboratory phases.
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Affiliation(s)
- Huub H van Rossum
- Department of Laboratory Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Stefan Holdenrieder
- Institute for Laboratory Medicine, German Heart Centre, Technical University of Munich, Munich, Germany
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Yu S, Shin KH, Shin S, Lee H, Yoo SJ, Jun KR, Shin H, Kim S. Practical delta check limits for tumour markers in different clinical settings. Clin Chem Lab Med 2023; 61:1829-1840. [PMID: 36994761 DOI: 10.1515/cclm-2022-1098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 03/19/2023] [Indexed: 03/31/2023]
Abstract
OBJECTIVES Few studies have reported on delta checks for tumour markers, even though these markers are often evaluated serially. Therefore, this study aimed to establish a practical delta check limit in different clinical settings for five tumour markers: alpha-fetoprotein, cancer antigen 19-9, cancer antigen 125, carcinoembryonic antigen, and prostate-specific antigen. METHODS Pairs of patients' results (current and previous) for five tumour markers between 2020 and 2021 were retrospectively collected from three university hospitals. The data were classified into three subgroups, namely: health check-up recipient (subgroup H), outpatient (subgroup O), and inpatient (subgroup I) clinics. The check limits of delta percent change (DPC), absolute DPC (absDPC), and reference change value (RCV) for each test were determined using the development set (the first 18 months, n=179,929) and then validated and simulated by applying the validation set (the last 6 months, n=66,332). RESULTS The check limits of DPC and absDPC for most tests varied significantly among the subgroups. Likewise, the proportions of samples requiring further evaluation, calculated by excluding samples with both current and previous results within the reference intervals, were 0.2-2.9% (lower limit of DPC), 0.2-2.7% (upper limit of DPC), 0.3-5.6% (absDPC), and 0.8-35.3% (RCV99.9%). Furthermore, high negative predictive values >0.99 were observed in all subgroups in the in silico simulation. CONCLUSIONS Using real-world data, we found that DPC was the most appropriate delta-check method for tumour markers. Moreover, Delta-check limits for tumour markers should be applied based on clinical settings.
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Affiliation(s)
- Shinae Yu
- Department of Laboratory Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
| | - Kyung-Hwa Shin
- Department of Laboratory Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan, Republic of Korea
| | - Sunghwan Shin
- Department of Laboratory Medicine, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Republic of Korea
| | - Hyeyoung Lee
- Department of Laboratory Medicine, International St. Mary's Hospital, College of Medicine, Catholic Kwandong University, Incheon, Republic of Korea
| | - Soo Jin Yoo
- Department of Laboratory Medicine, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, Republic of Korea
| | - Kyung Ran Jun
- Department of Laboratory Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Republic of Korea
| | - Hangsik Shin
- Department of Digital Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sollip Kim
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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Coşkun A, Sandberg S, Unsal I, Cavusoglu C, Serteser M, Kilercik M, Aarsand AK. Personalized and Population-Based Reference Intervals for 48 Common Clinical Chemistry and Hematology Measurands: A Comparative Study. Clin Chem 2023; 69:1009-1030. [PMID: 37525518 DOI: 10.1093/clinchem/hvad113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 07/10/2023] [Indexed: 08/02/2023]
Abstract
BACKGROUND Personalized reference intervals (prRIs) have the potential to improve individual patient follow-up as compared to population-based reference intervals (popRI). In this study, we estimated popRI and prRIs for 48 clinical chemistry and hematology measurands using samples from the same reference individuals and explored the effect of using group-based and individually based biological variation (BV) estimates to derive prRIs. METHODS 143 individuals (median age 28 years) were included in the study and had fasting blood samples collected once. From this population, 41 randomly selected subjects had samples collected weekly for 5 weeks. PopRIs were estimated according to Clinical Laboratory Standards Institute EP28 and within-subject BV (CVI) were estimated by CV-ANOVA. Data were assessed for trends and outliers prior to calculation of individual prRIs, based on estimates of (a) within-person BV (CVP), (b) CVI derived in this study, and (c) publically available CVI estimates. RESULTS For most measurands, the individual prRI ranges were smaller than the popRI range, but overall about half the study participants had a prRI wider than the popRI for 5 or more out of 48 measurands. The dispersion of prRIs based on CVP was wider than that of prRIs based on CVI. CONCLUSION The prRIs derived in our study varied significantly between different individuals, especially if based on CVP. Our results highlight the limitations of popRIs in interpreting test results of individual patients. If sufficient data from a steady-state situation are available, using prRI based on CVP estimates will provide a RI most specific for an individual patient.
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Affiliation(s)
- Abdurrahman Coşkun
- Acibadem Labmed Clinical Laboratories, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Sverre Sandberg
- Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway
- Norwegian Porphyria Centre, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Department of Global Health and Primary Care, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
| | - Ibrahim Unsal
- Acibadem Labmed Clinical Laboratories, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Coskun Cavusoglu
- Acibadem Labmed Clinical Laboratories, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Mustafa Serteser
- Acibadem Labmed Clinical Laboratories, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Meltem Kilercik
- Acibadem Labmed Clinical Laboratories, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Aasne K Aarsand
- Norwegian Porphyria Centre, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Department of Global Health and Primary Care, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
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Guillaume L, Chapelle V, Deltombe M, Nevraumont A, Mairesse A, Maisin D, Gruson D. Biological variation of CA 15-3, CA 125 and HE 4 on lithium heparinate plasma in apparently healthy Caucasian volunteers. Clin Chem Lab Med 2023; 61:1319-1326. [PMID: 37043610 DOI: 10.1515/cclm-2022-0966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 03/17/2023] [Indexed: 04/14/2023]
Abstract
OBJECTIVES Tumor markers are well-known for being important tools in the support of diagnosis, monitoring of treatment efficacy and follow-up of cancers. CA 125, CA 15-3 and HE 4 have demonstrated potential efficacy in other clinical indications. The main objective was to evaluate the biological variation of these glycoproteins using two different immunoassays in an apparently healthy Caucasian population. METHODS Nineteen healthy volunteers including 11 women and 8 men were sampled weekly for 5 consecutive weeks. Samples were analyzed in duplicate on Lumipulse® G600II (Fujirebio) and on the Cobas e602 (Roche Diagnostics) analyzers. After assessment of normality, exclusion of outliers and analysis of homogeneity of variance, analytical variation (CVA), within-subject biological variation (CVI) and between-subject biological variation (CVG) were determined using a nested ANOVA. RESULTS CVA, CVI and CVG were determined on both analyzers and both genders. For CA 125, the CVA ranges from 1.0 to 3.4%, the CVI from 5.7 to 13.8% and the CVG from 32.2 to 42.9%. For CA 15-3, the CVA is between 1.1 and 3.4%, the CVI between 3.9 and 6.5% and the CVG between 43.7 and 196.9%. Lastly, HE 4 has CVA values between 1.4 and 2.4%, CVI between 5.1 and 10.5% and CVG between 7.1 and 12.6%. CONCLUSIONS Our study provided updated data on the biological variation of CA 125, HE 4 and CA 15-3. These data allow to improve the clinical interpretation and thus the management of the patient.
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Affiliation(s)
- Louise Guillaume
- Department of Clinical Biochemistry, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Virginie Chapelle
- Department of Clinical Biochemistry, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Matthieu Deltombe
- Department of Clinical Biochemistry, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Arnaud Nevraumont
- Department of Clinical Biochemistry, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Antoine Mairesse
- Department of Clinical Biochemistry, Cliniques de l'Europe de Bruxelles, Brussels, Belgium
| | - Diane Maisin
- Department of Clinical Biochemistry, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Damien Gruson
- Department of Clinical Biochemistry, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
- Pôle de recherche en Endocrinologie, Diabète et Nutrition, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium
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Wojtalewicz N, Vierbaum L, Kaufmann A, Schellenberg I, Holdenrieder S. Longitudinal Evaluation of AFP and CEA External Proficiency Testing Reveals Need for Method Harmonization. Diagnostics (Basel) 2023; 13:2019. [PMID: 37370914 DOI: 10.3390/diagnostics13122019] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/02/2023] [Accepted: 06/04/2023] [Indexed: 06/29/2023] Open
Abstract
The glycoproteins alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) have long been approved as biomarkers for diagnosing and monitoring tumors. International Reference Preparations (IRPs) have been around since 1975. Nevertheless, manufacturer-dependent differences have been reported, indicating a lack of harmonization. This paper analyzes data from 15 external quality assessment (EQA) surveys conducted worldwide between 2018 and 2022. The aim was to gain insight into the longitudinal development of manufacturer-dependent differences for CEA and AFP. In each survey, participating laboratories received two samples with different tumor marker levels. Inter- and intra-assay variability was analyzed and the mean 80% and 90% of the manufacturer collectives were compared to the evaluation criteria of the German Medical Association (RiliBÄK). The median EQA results for CEA revealed manufacturer-dependent differences between the highest and lowest collective of up to 100%; for AFP, the median differences mostly remained below 40%. The coefficients of variation were predominantly low for both markers. We concluded that the current assays for AFP and CEA detection are better harmonized than previously reported. The assays displayed a good robustness; however, a narrowing of the current assessment limits in EQA schemes could further enhance the quality of laboratory testing.
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Affiliation(s)
- Nathalie Wojtalewicz
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Ubierstr. 20, 40223 Duesseldorf, Germany
| | - Laura Vierbaum
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Ubierstr. 20, 40223 Duesseldorf, Germany
| | - Anne Kaufmann
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Ubierstr. 20, 40223 Duesseldorf, Germany
| | - Ingo Schellenberg
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Ubierstr. 20, 40223 Duesseldorf, Germany
- Institute of Bioanalytical Sciences (IBAS), Center of Life Sciences, Anhalt University of Applied Sciences, Strenzfelder Allee 28, 06406 Bernburg, Germany
| | - Stefan Holdenrieder
- INSTAND e.V., Society for Promoting Quality Assurance in Medical Laboratories, Ubierstr. 20, 40223 Duesseldorf, Germany
- Institute of Laboratory Medicine, Munich Biomarker Research Center, Deutsches Herzzentrum München, Technische Universität München, 80636 Munich, Germany
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Song Z, Zhang J, Liu B, Wang H, Bi L, Xu Q. Practical application of European biological variation combined with Westgard Sigma Rules in internal quality control. Clin Chem Lab Med 2022; 60:1729-1735. [PMID: 36036501 DOI: 10.1515/cclm-2022-0327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/17/2022] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Westgard Sigma Rules is a statistical tool available for quality control. Biological variation (BV) can be used to set analytical performance specifications (APS). The European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) regularly updates BV data. However, few studies have used robust BV data to determine quality goals and design a quality control strategy for tumor markers. The aim of this study was to derive APS for tumor markers from EFLM BV data and apply Westgard Sigma Rules to establish internal quality control (IQC) rules. METHODS Precision was calculated from IQC data, and bias was obtained from the relative deviation of the External quality assurance scheme (EQAS) group mean values and laboratory-measured values. Total allowable error (TEa) was derived using EFLM BV data. After calculating sigma metrics, the IQC strategy for each tumor marker was determined according to Westgard Sigma Rules. RESULTS Sigma metrics achieved for each analyte varied with the level of TEa. Most of these tumor markers except neuron-specific enolase reached 3σ or better based on TEamin. With TEades and TEaopt set as the quality goals, almost all analytes had sigma values below 3. Set TEamin as quality goal, each analyte matched IQC muti rules and numbers of control measurements according to sigma values. CONCLUSIONS Quality goals from the EFLM BV database and Westgard Sigma Rules can be used to develop IQC strategy for tumor markers.
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Affiliation(s)
- Zhenzhen Song
- Department of Clinical Laboratory, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, P. R. China.,Zhengzhou Key Laboratory of Digestive System Tumor Marker Diagnosis, Zhengzhou, Henan, P. R. China
| | - Jiajia Zhang
- Department of Clinical Laboratory, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, P. R. China.,Zhengzhou Key Laboratory of Digestive System Tumor Marker Diagnosis, Zhengzhou, Henan, P. R. China
| | - Bing Liu
- Department of Clinical Laboratory, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, P. R. China.,Zhengzhou Key Laboratory of Digestive System Tumor Marker Diagnosis, Zhengzhou, Henan, P. R. China
| | - Hao Wang
- Department of Clinical Laboratory, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, P. R. China.,Zhengzhou Key Laboratory of Digestive System Tumor Marker Diagnosis, Zhengzhou, Henan, P. R. China
| | - Lijun Bi
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, P. R. China
| | - Qingxia Xu
- Department of Clinical Laboratory, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, P. R. China.,Zhengzhou Key Laboratory of Digestive System Tumor Marker Diagnosis, Zhengzhou, Henan, P. R. China
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11
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Lippi G, Plebani M. Clinical Chemistry and laboratory medicine: enjoying the present and assessing the future. Clin Chem Lab Med 2022; 60:1313-1315. [PMID: 35822713 DOI: 10.1515/cclm-2022-0627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Giuseppe Lippi
- Section of Clinical Biochemistry and School of Medicine, University of Verona, Verona, Italy
| | - Mario Plebani
- Department of Medicine-DIMED, University of Padova, Padova, Italy
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12
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Dittadi R, Fabricio ASC, Gion M. Biological variation and reference change value as decision criteria in clinical use of tumor biomarkers. Are they really useful? Clin Chem Lab Med 2022; 60:e136-e137. [PMID: 35263822 DOI: 10.1515/cclm-2022-0047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 02/23/2022] [Indexed: 11/15/2022]
Affiliation(s)
- Ruggero Dittadi
- Laboratory Medicine Unit, Department of Clinical Pathology, Ospedale dell'Angelo, Azienda ULSS 3 Serenissima, Mestre, Venice, Italy.,Regional Center for Biomarkers, Department of Clinical Pathology, Azienda ULSS 3 Serenissima, Venice, Italy
| | | | - Massimo Gion
- Regional Center for Biomarkers, Department of Clinical Pathology, Azienda ULSS 3 Serenissima, Venice, Italy
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13
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Marques-Garcia F, Boned B, González-Lao E, Braga F, Carobene A, Coskun A, Díaz-Garzón J, Fernández-Calle P, Perich MC, Simon M, Jonker N, Aslan B, Bartlett WA, Sandberg S, Aarsand AK. Critical review and meta-analysis of biological variation estimates for tumor markers. Clin Chem Lab Med 2022; 60:494-504. [PMID: 35143717 DOI: 10.1515/cclm-2021-0725] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 02/01/2022] [Indexed: 01/21/2023]
Abstract
OBJECTIVES Biological variation data (BV) can be used for different applications, but this depends on the availability of robust and relevant BV data. In this study, we aimed to summarize and appraise BV studies for tumor markers, to examine the influence of study population characteristics and concentrations on BV estimates and to discuss the applicability of BV data for tumor markers in clinical practice. METHODS Studies reporting BV data for tumor markers related to gastrointestinal, prostate, breast, ovarian, haematological, lung, and dermatological cancers were identified by a systematic literature search. Relevant studies were evaluated by the Biological Variation Data Critical Appraisal Checklist (BIVAC) and meta-analyses were performed for BIVAC compliant studies to deliver global estimates of within-subject (CVI) and between-subject (CVG) BV with 95% CI. RESULTS The systematic review identified 49 studies delivering results for 22 tumor markers; four papers received BIVAC grade A, 3 B, 27 C and 15 D. Out of these, 29 CVI and 29 CVG estimates met the criteria to be included in the meta-analysis. Robust data are lacking to conclude on the relationship between BV and different disease states and tumor marker concentrations. CONCLUSIONS This review identifies a lack of high-quality BV studies for many tumor markers and a need for delivery of BIVAC compliant studies, including in different, disease states and tumor marker concentrations. As of yet, the state-of-the-art may still be the most appropriate model to establish analytical performance specifications for the majority of tumor markers.
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Affiliation(s)
- Fernando Marques-Garcia
- Biochemistry Department, Metropolitan North Clinical Laboratory (LCMN), Germans Trias i Pujol Universitary Hospital, Badalona, Barcelona, Spain.,Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain
| | - Beatriz Boned
- Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain.,Royo Villanova Hospital, Zaragoza, Spain
| | - Elisabet González-Lao
- Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain.,Quality Healthcare Consulting, Grupo ACMS, Barcelona, Spain
| | - Federica Braga
- Research Centre for Metrological Traceability in Laboratory Medicine (CIRME), University of Milan, Milan, Italy
| | - Anna Carobene
- Servizio Medicina di Laboratorio, Ospedale San Raffaele, Milan, Italy
| | - Abdurrahman Coskun
- School of Medicine, Acibadem Mehmet Ali Aydınlar University, Atasehir, Istanbul, Turkey
| | - Jorge Díaz-Garzón
- Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain.,Department of Laboratory Medicine, La Paz University Hospital, Madrid, Spain
| | - Pilar Fernández-Calle
- Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain.,Department of Laboratory Medicine, La Paz University Hospital, Madrid, Spain
| | - Maria Carmen Perich
- Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain
| | - Margarida Simon
- Spanish Society of Laboratory Medicine (SEQCML), Analytical Quality Commission, Barcelona, Spain.,Consortium of Laboratory Intercomarcal Alt Penedès and Garraf l'Anoia, Vilafranca del Penedès, Spain
| | - Niels Jonker
- Certe-Wilhelmina Ziekenhuis Assen, Assen, The Netherlands
| | - Berna Aslan
- Institute for Quality Management in Healthcare (IQMH), Centre for Proficiency Testing, Toronto, Ontario, Canada
| | | | - Sverre Sandberg
- Department of Medical Biochemistry and Pharmacology, Norwegian Porphyria Centre, Haukeland University Hospital, Bergen, Norway.,Norwegian Organization for Quality Improvement of Laboratory Examinations (NOKLUS), Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Global Health and Primary Care, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Aasne K Aarsand
- Department of Medical Biochemistry and Pharmacology, Norwegian Porphyria Centre, Haukeland University Hospital, Bergen, Norway.,Norwegian Organization for Quality Improvement of Laboratory Examinations (NOKLUS), Haraldsplass Deaconess Hospital, Bergen, Norway
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14
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Sandberg S, Carobene A, Aarsand AK. Biological variation - eight years after the 1st Strategic Conference of EFLM. Clin Chem Lab Med 2022; 60:465-468. [PMID: 35138052 DOI: 10.1515/cclm-2022-0086] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Sverre Sandberg
- Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Medical Biochemistry and Pharmacology, Norwegian Porphyria Centre, Haukeland University Hospital, Bergen, Norway.,Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
| | - Anna Carobene
- Laboratory Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Aasne K Aarsand
- Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Medical Biochemistry and Pharmacology, Norwegian Porphyria Centre, Haukeland University Hospital, Bergen, Norway
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15
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Coskun A, Sandberg S, Unsal I, Yavuz FG, Cavusoglu C, Serteser M, Kilercik M, Aarsand AK. Personalized reference intervals - statistical approaches and considerations. Clin Chem Lab Med 2021; 60:629-635. [PMID: 34894385 DOI: 10.1515/cclm-2021-1066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/02/2021] [Indexed: 11/15/2022]
Abstract
For many measurands, physicians depend on population-based reference intervals (popRI), when assessing laboratory test results. The availability of personalized reference intervals (prRI) may provide a means to improve the interpretation of laboratory test results for an individual. prRI can be calculated using estimates of biological and analytical variation and previous test results obtained in a steady-state situation. In this study, we aim to outline statistical approaches and considerations required when establishing and implementing prRI in clinical practice. Data quality assessment, including analysis for outliers and trends, is required prior to using previous test results to estimate the homeostatic set point. To calculate the prRI limits, two different statistical models based on 'prediction intervals' can be applied. The first model utilizes estimates of 'within-person biological variation' which are based on an individual's own data. This model requires a minimum of five previous test results to generate the prRI. The second model is based on estimates of 'within-subject biological variation', which represents an average estimate for a population and can be found, for most measurands, in the EFLM Biological Variation Database. This model can be applied also when there are lower numbers of previous test results available. The prRI offers physicians the opportunity to improve interpretation of individuals' test results, though studies are required to demonstrate if using prRI leads to better clinical outcomes. We recommend that both popRIs and prRIs are included in laboratory reports to aid in evaluating laboratory test results in the follow-up of patients.
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Affiliation(s)
- Abdurrahman Coskun
- Acibadem Labmed Clinical Laboratories, Istanbul, Turkey
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Sverre Sandberg
- Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway
- Norwegian Porphyria Centre and Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Department of Global Health and Primary Care, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway
| | - Ibrahim Unsal
- Acibadem Labmed Clinical Laboratories, Istanbul, Turkey
| | - Fulya G Yavuz
- Department of Statistics, Faculty of Arts and Sciences, Middle East Technical University, Ankara, Turkey
| | | | - Mustafa Serteser
- Acibadem Labmed Clinical Laboratories, Istanbul, Turkey
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Meltem Kilercik
- Acibadem Labmed Clinical Laboratories, Istanbul, Turkey
- Department of Medical Biochemistry, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Aasne K Aarsand
- Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway
- Norwegian Porphyria Centre and Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
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16
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van Rossum HH, Meng QH, Ramanathan LV, Holdenrieder S. A word of caution on using tumor biomarker reference change values to guide medical decisions and the need for alternatives. Clin Chem Lab Med 2021; 60:553-555. [PMID: 34648697 DOI: 10.1515/cclm-2021-0933] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 09/13/2021] [Indexed: 12/13/2022]
Affiliation(s)
- Huub H van Rossum
- Department of Laboratory Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Qing H Meng
- Department of Laboratory Medicine, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lakshmi V Ramanathan
- Clinical Chemistry Service, Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Stefan Holdenrieder
- Institute of Laboratory Medicine, Munich Biomarker Research Center, Deutsches Herzzentrum München, Technische Universität Munchen, Munich, Germany
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17
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Carobene A, Aarsand AK, Bartlett WA, Coskun A, Diaz-Garzon J, Fernandez-Calle P, Guerra E, Jonker N, Locatelli M, Plebani M, Sandberg S, Ceriotti F. The European Biological Variation Study (EuBIVAS): a summary report. Clin Chem Lab Med 2021; 60:505-517. [PMID: 34049424 DOI: 10.1515/cclm-2021-0370] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 05/14/2021] [Indexed: 12/20/2022]
Abstract
Biological variation (BV) data have many important applications in laboratory medicine. Concerns about quality of published BV data led the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) 1st Strategic Conference to indicate need for new studies to generate BV estimates of required quality. In response, the EFLM Working Group on BV delivered the multicenter European Biological Variation Study (EuBIVAS). This review summarises the EuBIVAS and its outcomes. Serum/plasma samples were taken from 91 ostensibly healthy individuals for 10 consecutive weeks at 6 European centres. Analysis was performed by Siemens ADVIA 2400 (clinical chemistry), Cobas Roche 8000, c702 and e801 (proteins and tumor markers/hormones respectively), ACL Top 750 (coagulation parameters), and IDS iSYS or DiaSorin Liaison (bone biomarkers). A strict preanalytical and analytical protocol was applied. To determine BV estimates with 95% CI, CV-ANOVA after analysis of outliers, homogeneity and trend analysis or a Bayesian model was applied. EuBIVAS has so far delivered BV estimates for 80 different measurands. Estimates for 10 measurands (Non-HDL Cholesterol, S100-β protein, neuron-specific enolase, soluble transferrin receptor, intact fibroblast growth-factor-23, uncarboxylated-unphosphorylated matrix-Gla protein, human epididymis protein-4, free, conjugated and %free prostate-specific antigen), prior to EuBIVAS, have not been available. BV data for creatinine and troponin I were obtained using two analytical methods in each case. The EuBIVAS has delivered high-quality BV data for a wide range of measurands. The BV estimates are for many measurands lower than those previously reported, having an impact on the derived analytical performance specifications and reference change values.
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Affiliation(s)
- Anna Carobene
- Laboratory Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Aasne K Aarsand
- Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway.,Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway
| | | | - Abdurrahman Coskun
- Acibadem Mehmet Ali Aydınlar University, School of Medicine, Istanbul, Turkey
| | - Jorge Diaz-Garzon
- Hospital Universitario La Paz, and Quality Analytical Commission of Spanish Society of Laboratory Medicine (SEQCML), Madrid, Spain
| | - Pilar Fernandez-Calle
- Hospital Universitario La Paz, and Quality Analytical Commission of Spanish Society of Laboratory Medicine (SEQCML), Madrid, Spain
| | - Elena Guerra
- Laboratory Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Niels Jonker
- Certe-Wilhelmina Ziekenhuis Assen, Europaweg-Zuid 1, Assen, The Netherlands
| | - Massimo Locatelli
- Laboratory Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Mario Plebani
- Department of Laboratory Medicine, University Hospital of Padova, Padova, Italy
| | - Sverre Sandberg
- Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway.,Norwegian Organization for Quality Improvement of Laboratory Examinations (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
| | - Ferruccio Ceriotti
- Central Laboratory, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
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