[Clinical biological features of mixed myeloid diseases]

To characterize patients with mixed myeloid neoplasias with proliferation of neutrophils, platelets and eosinophils.

Examination and treatment results were analysed for patients with atypical myeloid leukemia (n = 4), myelodysplastic syndrome (MDS, n = 1) and thrombocytosis, MDS and eosinophilia (n = 1). The examination included morphological, histological, cytogenetic and molecular tests.

One patient with atypical chronic myeloid leukemia was prior diagnosed to have primarily MDS with a typical aberration of chromosome 5. Two other patients had an initial morphological picture of resistant anemia with blast excess, signs of myeloproliferation and extramedullary hemopoiesis. One and two months after the first examination they received transfusions of erythrocytic mass. Just then they were found to have splenomegaly and leukocytosis due to proliferating and maturating forms of neutrophils. The course of the disease in patients with MDS, thrombocytosis and normal karyotype and in patients with MDS, eosinophilia and combined chromosomal breaks including translocation (3;12)(q21;p13) was characterized by resistance to standard programs of polychemotherapy and transformation into acute myeloblastic leukemia.

In some cases atypical CML is a stage of a natural course of MDS. Some MDS variants with eosinophilia and thrombocytosis should be referred to the group of mixed myeloid neoplasias.