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Harmonization of molecular monitoring of CML therapy in Europe


The high efficacy of the standard treatment of chronic myeloid leukemia (CML) with imatinib has prompted the need for accurate methods to monitor response at levels below the landmark of complete cytogenetic remission. Quantification of BCR–ABL transcripts has proven to be the most sensitive method available, and has shown prognostic impact with regard to progression-free survival. Until recently, variations in methods used to quantify BCR–ABL made it difficult to compare results between laboratories. An international program is now underway to harmonize the reporting of results according to an international scale (IS). In this review, we consider the background to the IS and the progress that has been made to date, with a particular focus on ongoing harmonization efforts in Europe. We provide recommendations for the propagation of the IS by national or regional laboratory networks.

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This work was supported by the European LeukemiaNet, sponsored by the European Union, Sixth Framework Programme, contact no. LSHC-CT-2004-503216 (European LeukemiaNet) and Novartis Pharmaceuticals as part of the EUTOS for CML collaboration, and the German José-Carreras-Foundation (AH, DJCLS H 03/01).

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Correspondence to A Hochhaus.

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Müller, M., Cross, N., Erben, P. et al. Harmonization of molecular monitoring of CML therapy in Europe. Leukemia 23, 1957–1963 (2009).

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  • chronic myeloid leukemia
  • molecular monitoring
  • international scale
  • conversion factor
  • EUTOS for CML

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