An Exercise in Extrapolation: Clinical Management of Atypical CML, MDS/MPN-Unclassifiable, and MDS/MPN-RS-T

Curr Hematol Malig Rep. 2016 Dec;11(6):425-433. doi: 10.1007/s11899-016-0350-1.


According to the recently published 2016 World Health Organization (WHO) classification of myeloid malignancies, myelodysplastic/myeloproliferative neoplasms (MDS/MPN) include atypical chronic myeloid leukemia (aCML), MDS/MPN-unclassifiable (MDS/MPN-U), chronic myelomonocytic leukemia (CMML), juvenile myelomonocytic leukemia (JMML), and MDS/MPN ring sideroblasts with thrombocytosis (MDS/MPN-RS-T). MDS/MPN-RS-T was previously a provisional category known as refractory anemia with ring sideroblasts with thrombocytosis (RARS-T) which has now attained a distinct designation in the 2016 WHO classification. In this review, we focus on biology and management of aCML, MDS/MPN-U, and MDS/MPN-RS-T. There is considerable overlap between these entities which we attempt to further elucidate in this review. We also discuss recent advances in the field of molecular landscape that further defines and characterizes this heterogeneous group of disorders. The paucity of clinical trials available secondary to unclear pathogenesis and rarity of these diseases makes the management of these entities clinically challenging. This review summarizes some of the current knowledge of the molecular pathogenesis and suggested treatment guidelines based on the available data.

Keywords: Chronic myelomonocytic leukemia; Juvenile myelomonocytic leukemia; Myelodysplastic syndrome; Myeloproliferative neoplasms.

Publication types

  • Review

MeSH terms

  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism
  • Cytogenetics
  • DNA Copy Number Variations
  • Hematologic Neoplasms / diagnosis
  • Hematologic Neoplasms / drug therapy
  • Hematologic Neoplasms / genetics
  • Hematologic Neoplasms / pathology
  • Iron Overload / complications
  • Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative / diagnosis
  • Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative / drug therapy
  • Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative / genetics
  • Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative / pathology*
  • Myelodysplastic-Myeloproliferative Diseases / diagnosis
  • Myelodysplastic-Myeloproliferative Diseases / drug therapy
  • Myelodysplastic-Myeloproliferative Diseases / genetics
  • Myelodysplastic-Myeloproliferative Diseases / pathology*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Protein Kinase Inhibitors / therapeutic use
  • Receptors, Colony-Stimulating Factor / genetics
  • Receptors, Colony-Stimulating Factor / metabolism
  • Thrombocytosis / complications


  • CSF3R protein, human
  • Carrier Proteins
  • Nuclear Proteins
  • Protein Kinase Inhibitors
  • Receptors, Colony-Stimulating Factor
  • SETBP1 protein, human