Treatment of chronic myeloid leukemia (CML) with tyrosine kinase inhibitors has advanced to a stage where many patients achieve very low or undetectable levels of disease. Remarkably, some of these patients remain in sustained remission when treatment is withdrawn, suggesting that they may be at least operationally cured of their disease. Accurate definition of deep molecular responses (MRs) is therefore increasingly important for optimal patient management and comparison of independent data sets. We previously published proposals for broad standardized definitions of MR at different levels of sensitivity. Here we present detailed laboratory recommendations, developed as part of the European Treatment and Outcome Study for CML (EUTOS), to enable testing laboratories to score MR in a reproducible manner for CML patients expressing the most common BCR-ABL1 variants.

] Department of Clinical Medicine and Surgery University 'Federico II' of Naples Naples Italy [2] CEINGE Biotecnologie Avanzate Naples Italy

] Faculty of Medicine University of Southampton Southampton UK [2] National Genetics Reference Laboratory Salisbury District Hospital Salisbury UK

3 Medizinische Klinik Universitätsmedizin Mannheim Mannheim Germany

Abteilung für Hämatologie und internistische Onkologie Universität Leipzig Leipzig Germany

Abteilung Hämatologie Onkologie Klinik für Innere Medizin 2 Universitätsklinikum Jena Jena Germany

Children's Cancer Research Institute LabDia Labordiagnostik and Medical University Vienna Austria

Department of Clinical and Biological Science University of Turin Turin Italy

Department of Clinical Genetics Laboratory Medicine Lund University Lund Sweden

Department of Clinical Medicine and Surgery University 'Federico II' of Naples Naples Italy

Department of Experimental Diagnostic and Specialty Medicine University of Bologna Bologna Italy

Department of Molecular Medicine and Surgery Clinical Genetics Karolinska Institutet Stockholm Sweden

Hematology Department Fundeni Clinical Institute University of Medicine and Pharmacy 'Carol Davila' Bucharest Romania

Hematology Department Jagiellonian University Krakow Poland

Hematopathology Unit Hospital Clinic IDIBAPS Barcelona Spain

Imperial Molecular Pathology Laboratory Centre for Haematology Imperial College London London UK

Institute of Hematology and Blood Transfusion Prague Czech Republic

Klinisk Biokemi Vejle Sygehus Vejle Denmark

Laboratoire Hematologie CHU Bordeaux Hematopoiese Leucemique et Cibles Therapeutiques INSERM U1035 Université Bordeaux Bordeaux France

Molecular Diagnostics Laboratory Department of Hematology University Hospital Bern Bern Switzerland

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Baccarani M, Deininger MW, Rosti G, Hochhaus A, Soverini S, Apperley JF, et al. European LeukemiaNet recommendations for the management of chronic myeloid leukemia: 2013. Blood. 2013;122:872–884. PubMed PMC

O'Brien S, Radich JP, Abboud CN, Akhtari M, Altman JK, Berman E, et al. Chronic myelogenous leukemia, version 1.2015. J Natl Compr Canc Netw. 2014;12:1590–1610. PubMed

Hughes T, Deininger M, Hochhaus A, Branford S, Radich J, Kaeda J, et al. Monitoring CML patients responding to treatment with tyrosine kinase inhibitors: review and recommendations for harmonizing current methodology for detecting BCR-ABL transcripts and kinase domain mutations and for expressing results. Blood. 2006;108:28–37. PubMed PMC

Cross NC. Standardisation of molecular monitoring for chronic myeloid leukaemia. Best Pract Res Clin Haematol. 2009;22:355–365. PubMed

Branford S, Cross NC, Hochhaus A, Radich J, Saglio G, Kaeda J, et al. Rationale for the recommendations for harmonizing current methodology for detecting BCR-ABL transcripts in patients with chronic myeloid leukaemia. Leukemia. 2006;20:1925–1930. PubMed

Branford S, Fletcher L, Cross NC, Muller MC, Hochhaus A, Kim DW, et al. Desirable performance characteristics for BCR-ABL measurement on an international reporting scale to allow consistent interpretation of individual patient response and comparison of response rates between clinical trials. Blood. 2008;112:3330–3338. PubMed

White HE, Matejtschuk P, Rigsby P, Gabert J, Lin F, Lynn Wang Y, et al. Establishment of the first World Health Organization International Genetic Reference Panel for quantitation of BCR-ABL mRNA. Blood. 2010;116:e111–e117. PubMed

White HE, Hedges J, Bendit I, Branford S, Colomer D, Hochhaus A, et al. Establishment and validation of analytical reference panels for the standardization of quantitative BCR-ABL1 measurements on the international scale. Clin Chem. 2013;59:938–948. PubMed

Maute C, Nibourel O, Rea D, Coiteux V, Grardel N, Preudhomme C, et al. Calibration of BCR-ABL1 mRNA quantification methods using genetic reference materials is a valid strategy to report results on the international scale. Clin Biochem. 2014;47:1333–1336. PubMed

Hehlmann R, Grimwade D, Simonsson B, Apperley J, Baccarani M, Barbui T, et al. The European LeukemiaNet: achievements and perspectives. Haematologica. 2011;96:156–162. PubMed PMC

Saglio G, Kim DW, Issaragrisil S, le Coutre P, Etienne G, Lobo C, et al. Nilotinib versus imatinib for newly diagnosed chronic myeloid leukemia. N Engl J Med. 2010;362:2251–2259. PubMed

Kantarjian H, Shah NP, Hochhaus A, Cortes J, Shah S, Ayala M, et al. Dasatinib versus imatinib in newly diagnosed chronic-phase chronic myeloid leukemia. N Engl J Med. 2010;362:2260–2270. PubMed

Mahon FX, Rea D, Guilhot J, Guilhot F, Huguet F, Nicolini F, et al. Discontinuation of imatinib in patients with chronic myeloid leukaemia who have maintained complete molecular remission for at least 2 years: the prospective, multicentre Stop Imatinib (STIM) trial. Lancet Oncol. 2010;11:1029–1035. PubMed

Rousselot P, Charbonnier A, Cony-Makhoul P, Agape P, Nicolini FE, Varet B, et al. Loss of major molecular response as a trigger for restarting tyrosine kinase inhibitor therapy in patients with chronic-phase chronic myelogenous leukemia who have stopped imatinib after durable undetectable disease. J Clin Oncol. 2014;32:424–430. PubMed

Cross NC, White HE, Muller MC, Saglio G, Hochhaus A. Standardized definitions of molecular response in chronic myeloid leukemia. Leukemia. 2012;26:2172–2175. PubMed

Bustin SA, Benes V, Garson JA, Hellemans J, Huggett J, Kubista M, et al. The MIQE guidelines: minimum information for publication of quantitative real-time PCR experiments. Clin Chem. 2009;55:611–622. PubMed

White H, Deprez L, Corbisier P, Hall V, Lin F, Mazoua S, et al. A certified plasmid reference material for the standardisation of BCR-ABL1 mRNA quantification by eal time quantitative PCR. Leukemia. 2014;29:369–376. PubMed PMC

Gabert J, Beillard E, van der Velden VH, Bi W, Grimwade D, Pallisgaard N, et al. Standardization and quality control studies of 'real-time' quantitative reverse transcriptase polymerase chain reaction of fusion gene transcripts for residual disease detection in leukemia—a Europe Against Cancer program. Leukemia. 2003;17:2318–2357. PubMed

Branford S, Hughes T. Diagnosis and monitoring of chronic myeloid leukemia by qualitative and quantitative RT-PCR. Methods Mol Med. 2006;125:69–92. PubMed

Jennings LJ, Smith FA, Halling KC, Persons DL, Kamel-Reid S, Molecular Oncology Resource Committee of the College of American P Design and analytic validation of BCR-ABL1 quantitative reverse transcription polymerase chain reaction assay for monitoring minimal residual disease. Arch Pathol Lab Med. 2012;136:33–40. PubMed

Foroni L, Wilson G, Gerrard G, Mason J, Grimwade D, White HE, et al. Guidelines for the measurement of BCR-ABL1 transcripts in chronic myeloid leukaemia. Br J Haematol. 2011;153:179–190. PubMed

Beillard E, Pallisgaard N, van der Velden VH, Bi W, Dee R, van der Schoot E, et al. Evaluation of candidate control genes for diagnosis and residual disease detection in leukemic patients using 'real-time' quantitative reverse-transcriptase polymerase chain reaction (RQ-PCR)—a Europe against cancer program. Leukemia. 2003;17:2474–2486. PubMed

Goldman JM, Gale RP. What does MRD in leukemia really mean. Leukemia. 2014;28:1131. PubMed

CLSI Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures; Approved Guideline2nd edn. (EP17-A2)Clinical and Laboratory Standards Institute: Wayne, PA, USA; 2012

Morley AA, Latham S, Brisco MJ, Sykes PJ, Sutton R, Hughes E, et al. Sensitive and specific measurement of minimal residual disease in acute lymphoblastic leukemia. J Mol Diagn. 2009;11:201–210. PubMed PMC

Ladetto M, Lobetti-Bodoni C, Mantoan B, Ceccarelli M, Boccomini C, Genuardi E, et al. Persistence of minimal residual disease in bone marrow predicts outcome in follicular lymphomas treated with a rituximab-intensive program. Blood. 2013;122:3759–3766. PubMed

Morley AA. Digital PCR: a brief history. Biomol Detect Quantif. 2014;1:1–2. PubMed PMC

Goh HG, Lin M, Fukushima T, Saglio G, Kim D, Choi SY, et al. Sensitive quantitation of minimal residual disease in chronic myeloid leukemia using nanofluidic digital polymerase chain reaction assay. Leuk Lymphoma. 2011;52:896–904. PubMed

Jennings LJ, George D, Czech J, Yu M, Joseph L. Detection and quantification of BCR-ABL1 fusion transcripts by droplet digital PCR. J Mol Diagn. 2014;16:174–179. PubMed

Bose S, Deininger M, Gora-Tybor J, Goldman JM, Melo JV. The presence of typical and atypical BCR-ABL fusion genes in leukocytes of normal individuals: biologic significance and implications for the assessment of minimal residual disease. Blood. 1998;92:3362–3367. PubMed

Sobrinho-Simoes M, Wilczek V, Score J, Cross NC, Apperley JF, Melo JV. In search of the original leukemic clone in chronic myeloid leukemia patients in complete molecular remission after stem cell transplantation or imatinib. Blood. 2010;116:1329–1335. PubMed

Ross DM, Branford S, Seymour JF, Schwarer AP, Arthur C, Bartley PA, et al. Patients with chronic myeloid leukemia who maintain a complete molecular response after stopping imatinib treatment have evidence of persistent leukemia by DNA PCR. Leukemia. 2010;24:1719–1724. PubMed

Bartley PA, Ross DM, Latham S, Martin-Harris MH, Budgen B, Wilczek V, et al. Sensitive detection and quantification of minimal residual disease in chronic myeloid leukaemia using nested quantitative PCR for BCR-ABL DNA. Int J Lab Hematol. 2010;32:e222–e228. PubMed

Hromadnikova I, Houbova B, Hridelova D, Voslarova S, Kofer J, Komrska V, et al. Replicate real-time PCR testing of DNA in maternal plasma increases the sensitivity of non-invasive fetal sex determination. Prenat Diagn. 2003;23:235–238. PubMed

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Standardization of molecular monitoring of CML: results and recommendations from the European treatment and outcome study

Impact of BCR::ABL1 transcript type on RT-qPCR amplification performance and molecular response to therapy

Assessment of individual molecular response in chronic myeloid leukemia patients with atypical BCR-ABL1 fusion transcripts: recommendations by the EUTOS cooperative network

Analysis of chronic myeloid leukaemia during deep molecular response by genomic PCR: a traffic light stratification model with impact on treatment-free remission

European LeukemiaNet 2020 recommendations for treating chronic myeloid leukemia

Genotypes of SLC22A4 and SLC22A5 regulatory loci are predictive of the response of chronic myeloid leukemia patients to imatinib treatment

Development and evaluation of a secondary reference panel for BCR-ABL1 quantification on the International Scale

Interferon-α Revisited: Individualized Treatment Management Eased the Selective Pressure of Tyrosine Kinase Inhibitors on BCR-ABL1 Mutations Resulting in a Molecular Response in High-Risk CML Patients