Susanne Möbius1, Thomas Schenk1, Danny Himsel1, Jacqueline Maier2, Georg-Nikolaus Franke2, Susanne Saussele3, Christiane Pott4, Hajnalka Andrikovics5,6, Nora Meggyesi5,6, Katerina Machova-Polakova7, Hana Zizkova7, Tomáš Jurcek8,9, Semir Mesanovic10, Renata Zadro11, Enrico Gottardi12, Jens Haenig13, Peter Schuld13, Nicholas C P Cross14,15, Andreas Hochhaus1, Thomas Ernst16. 1. Abteilung Hämatologie und Internistische Onkologie, Klinik für Innere Medizin II, Universitätsklinikum Jena, Am Klinikum 1, 07740, Jena, Germany. 2. Abteilung für Hämatologie und internistische Onkologie, Universität Leipzig, Leipzig, Germany. 3. III. Medizinische Klinik, Universitätsmedizin Mannheim, Universität Heidelberg, Mannheim, Germany. 4. Second Medical Department, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany. 5. National Blood Service, Budapest, Hungary. 6. Central Hospital of Southern Pest, Budapest, Hungary. 7. Department of Molecular Genetics, Institute of Hematology and Blood Transfusion, Prague, Czech Republic. 8. Department of Internal Medicine, Hematology and Oncology, University Hospital Brno, Brno, Czech Republic. 9. Faculty of Medicine, Masaryk University Brno, Brno, Czech Republic. 10. Pathology Department, University Clinical Center Tuzla, Tuzla, Bosnia and Herzegovina. 11. University Hospital Center Zagreb, University of Zagreb, Faculty of Pharmacy and Biochemistry, Zagreb, Croatia. 12. Division of Internal Medicine and Hematology, University of Turin, Orbassano, Italy. 13. Novartis Oncology, Global Medical Affairs, Basel, Switzerland. 14. Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury, UK. 15. Faculty of Medicine, University of Southampton, Southampton, UK. 16. Abteilung Hämatologie und Internistische Onkologie, Klinik für Innere Medizin II, Universitätsklinikum Jena, Am Klinikum 1, 07740, Jena, Germany. thomas.ernst@med.uni-jena.de.
Abstract
PURPOSE: The advent of tyrosine kinase inhibitor (TKI) therapies has revolutionized the treatment of chronic myeloid leukemia (CML). The European LeukemiaNet (ELN) recommends quantification of BCR-ABL1 transcripts by real-time quantitative PCR every 3 months during TKI treatment. Since a proportion of patients in deep molecular response (DMR: MR4, MR4.5, MR5) maintain remission after treatment stop, assessment of DMR is crucial. However, systematically collected molecular data, monitored with sensitive standardized assays, are not available outside clinical trials. METHODS: Data were collected on the standardized assessment of molecular response in the context of real-life practice. BCR-ABL1 transcript levels after > 2 years of TKI therapy were evaluated for DMR by local laboratories as well as standardized EUTOS laboratories. Since standardized molecular monitoring is a prerequisite for treatment discontinuation, central surveillance of the performance of the participating laboratories was carried out. RESULTS: Between 2014 and 2017, 3377 peripheral blood samples from 1117 CML patients were shipped to 11 standardized reference laboratories in six European countries. BCR-ABL1 transcript types were b3a2 (41.63%), b2a2 (29.99%), b2a2/b3a2 (3.58%) and atypical (0.54%). For 23.72% of the patients, the initial transcript type had not been reported. Response levels (EUTOS laboratory) were: no MMR, n = 197 (6.51%); MMR, n = 496 (16.40%); MR4, n = 685 (22.64%); MR4.5, n = 937 (30.98%); MR5, n = 710 (23.47%). With a Cohen's kappa coefficient of 0.708, a substantial agreement between EUTOS-certified and local laboratories was shown. CONCLUSIONS: Multicenter DMR assessment is feasible in the context of real-life clinical practice in Europe. Information on the BCR-ABL1 transcript type at diagnosis is crucial to accurately monitor patients' molecular response during or after TKI therapy.
PURPOSE: The advent of tyrosine kinase inhibitor (TKI) therapies has revolutionized the treatment of chronic myeloid leukemia (CML). The European LeukemiaNet (ELN) recommends quantification of BCR-ABL1 transcripts by real-time quantitative PCR every 3 months during TKI treatment. Since a proportion of patients in deep molecular response (DMR: MR4, MR4.5, MR5) maintain remission after treatment stop, assessment of DMR is crucial. However, systematically collected molecular data, monitored with sensitive standardized assays, are not available outside clinical trials. METHODS: Data were collected on the standardized assessment of molecular response in the context of real-life practice. BCR-ABL1 transcript levels after > 2 years of TKI therapy were evaluated for DMR by local laboratories as well as standardized EUTOS laboratories. Since standardized molecular monitoring is a prerequisite for treatment discontinuation, central surveillance of the performance of the participating laboratories was carried out. RESULTS: Between 2014 and 2017, 3377 peripheral blood samples from 1117 CMLpatients were shipped to 11 standardized reference laboratories in six European countries. BCR-ABL1 transcript types were b3a2 (41.63%), b2a2 (29.99%), b2a2/b3a2 (3.58%) and atypical (0.54%). For 23.72% of the patients, the initial transcript type had not been reported. Response levels (EUTOS laboratory) were: no MMR, n = 197 (6.51%); MMR, n = 496 (16.40%); MR4, n = 685 (22.64%); MR4.5, n = 937 (30.98%); MR5, n = 710 (23.47%). With a Cohen's kappa coefficient of 0.708, a substantial agreement between EUTOS-certified and local laboratories was shown. CONCLUSIONS: Multicenter DMR assessment is feasible in the context of real-life clinical practice in Europe. Information on the BCR-ABL1 transcript type at diagnosis is crucial to accurately monitor patients' molecular response during or after TKI therapy.
Authors: Jonathan A Webster; Tara M Robinson; Amanda L Blackford; Erica Warlick; Anna Ferguson; Ivan Borrello; Marianna Zahurak; Richard J Jones; B Douglas Smith Journal: Leuk Res Date: 2021-11-02 Impact factor: 3.156