Mastering the multitude of monocytoses

I n this issue of the journal, Valent and coworkers report on diagnostic criteria for chronic myelomonocytic leukemia (CMML), CMML variants, and pre-CMML conditions. 1 These CMML disorders have always been like orphans, trying to find their place in a suitable environment. They are rare entities but share chromosomal, molecular, morphological, hematologic, clinical, and prognostic features with other diseases in the large family of myeloid malignancies. The French-American-British group classified CMML as a myelodysplastic syndrome (MDS), based on its similarity to refractory anemia with excess blasts, although CMML "may have little in common with MDS showing trilineage dyspoiesis" 2 and despite the fact that CMML features only minimal dysplasia in the erythroid lineage.