Revised response criteria for myelofibrosis: International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) and European LeukemiaNet (ELN) consensus report

Blood. 2013 Aug 22;122(8):1395-8. doi: 10.1182/blood-2013-03-488098. Epub 2013 Jul 9.


The current document is a revision of the International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) criteria for treatment response in myelofibrosis (MF) and represents a collaborative effort by the IWG-MRT and the European LeukemiaNet to objectively assess the value of new drugs in inducing morphologic remission or improvement in MF-associated symptomatic burden (MF-SB). Some of the changes in the current revision include stricter definitions of red cell transfusion dependency and independency and consideration of the Myeloproliferative Neoplasm Symptom Assessment Form as a tool to quantify meaningful changes in disease-related symptoms. Six response categories are listed: complete remission (CR) and partial remission signify treatment effects that are consistent with disease modification, whereas drug-induced improvements in MF-SB were annotated as clinical improvement, anemia response, spleen response, or symptoms response. Additional criteria are provided for progressive disease, stable disease, and relapse. The document also includes recommendations for assessing cytogenetic and molecular remissions, without mandating their inclusion for CR assignment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bone Marrow Neoplasms / diagnosis
  • Bone Marrow Neoplasms / drug therapy
  • Chronic Disease / drug therapy
  • Consensus
  • Disease Progression
  • Erythrocyte Transfusion / methods
  • Europe
  • Humans
  • International Cooperation
  • Medical Oncology / methods*
  • Medical Oncology / standards
  • Myeloproliferative Disorders / therapy
  • Practice Guidelines as Topic
  • Primary Myelofibrosis / diagnosis*
  • Primary Myelofibrosis / drug therapy*
  • Remission Induction
  • Treatment Outcome