Welcome international healthcare professionals

This site is no longer supported and will not be updated with new content. You are welcome to browse and download all content already included in the site. Please note you will have to register your email address to access the site.

You are here

Refined Medullary Blast and White Blood Cell Count Based Classification of Chronic Myelomonocytic Leukemias

Leukemia Research



  • we showed that proliferative CMML types do worse as compared to dysplastic types.
  • progression rates of CMML with <5% blasts are lower as compared to CMML I + II.
  • erythroid insufficiency of all CMML types is not as severe as in RCMD, RAEB I and II.
  • separate CMML with less than 5% medullary blast count from CMML I.


Since 2001, chronic myelomonocytic leukemia (CMML) is classified by the WHO as myeloproliferative/myelodysplastic neoplasm. Herein we tried to better describe CMML patients with regard to hematological characteristics and prognosis using data of the Duesseldorf registry. We created 6 CMML subgroups, by dividing dysplastic and proliferative CMML at the cut-off of white blood cell count of 13,000/μl and splitting these two groups into 3 subgroups: CMML 0 with <5% blasts (n = 101), CMML I with 5%-9% blasts (n = 204) and CMML II with 10%-19% blasts (n = 81). For comparison we included patients with RCMD, RAEB I and II. The newly created CMML 0 group had better prognosis than CMML I and II, median survival times were 31 months (ms), 19 ms and 13 ms, respectively (p < 0.001). Median survival times between the corresponding dysplastic and proliferative subgroups 0 and 1 differed significantly: CMML 0 dysplastic 48 ms and CMML 0 proliferative 17 ms (p = 0.03), CMML I dysplastic 29 ms and CMML I proliferative 15 ms (p = 0.008), CMML II dysplastic 17 ms and CMML II proliferative 10 ms (p = 0.09). Outcome of CMML patients worsens with increasing medullary blasts and when presenting as proliferative type. Therefore it is justified to separate CMML with <5% medullary blasts.

Keywords: CMML, MDS, MDS/MPN, Overlap, Prognosis, CPSS.


a Department of Hematology, Oncology and Clinical Immunology, Heinrich-Heine-University, Düsseldorf, Germany

b Department of Human Genetics and Anthropology, Heinrich-Heine-University, Düsseldorf, Germany

lowast Corresponding author. Department of Hematology, Oncology and Clinical Immunology Heinrich-Heine-University Moorenstr. 5 40225 Düsseldorf, Germany Tel.: +49 211 8117720 fax: +49 211 8118853.