[Mixed myelodysplastic and myeloproliferative syndromes]. / Smísené myelodysplastické a myeloproliferativní syndromy.

BACKGROUND: An injury to the hemopoietic stem cell may lead to the aplasia of hemopoiesis, myelodysplasia and to an unregulated myeloproliferation. There is not a strict demarcation of them, so that mixed syndromes can develop as are hypoplastic syndromes on one side and mixed myelodysplastic and myeloproliferative syndromes (MDS-MPS) on the other side. METHODS AND RESULTS: Among our 616 pts with MDS we looked for those cases, who had beside myelodysplasia signs of myeloproliferation with increased number of blood cells. They were examined in detail including bone-marrow histology, bone marrow cultivation, cytogenetics and bcr-abl gen. Signs of MDS-MPS were found in 22 patients at the first contact with the patient (13 patients had thrombocytemia and 9 patients had leukocytosis). Further 7 patients were diagnosed as MDS, proliferative syndrome developed after several months (MDS-MPS in evolution). The level of thrombocytemia was relatively stable, the number of leukocytes was progressive. All subtypes of MDS were found. All subjects had variable degree of anemia. Ring-sideroblasts and myelofibrosis were frequent finding in MDS-MPS. Men prevailed in patients with leukocytosis. Cytogenetic and cultivation findings were similar to MDS cases, deletion of long arm of chromosome 20 was present in 3 patients. Five patients transformed to acute myeloid leukemia. CONCLUSIONS: Sings of myelodysplasia and myeloproliferation were found in 4% of our MDS patients, designated as mixed myelodysplastic and myeloproliferative syndrome (MDS-MPS). In this syndrome beside evident signs of myelodysplasia thrombocythemia or leukocytosis with the release of bone marrow precursors are present. In only one case polycythemia was encountered.

[Monocytosis and myelomonocytic dysplasia in myelodysplastic syndrome]. / Monocytóza a myelomonocytární dysplazie u myelodysplastického syndromu.

Myelodysplastic syndrome (MDS) is frequently associated with monocytosis in the blood and myelomonocytic dysplasia in the bone marrow. In two groups of patients with MDS, all subtypes excluding CMML, the authors demonstrated that monocytosis was present in 15% of the patients in group I according to the haemogram at the time when the diagnosis was established and in 19% in group II where it was required that at least in half the haemograms throughout the course of the disease there were more than 10% monocytes. No difference was found in the prognosis of patients with monocytosis, as compared with patients with monocytopenia as regards the life span and frequency of transformation into AL. The cytogenetic and cultivation findings did not differ either. In some instances, in particular in patients with RA and RAS significant monocytosis was not associated with the expected proliferation of monocytoid cells in bone marrow. The authors assume that proliferation and differentiation of germ cells in the monocytic series is easier than in the granulocytic series and that monocytosis can be considered a manifestation of substituted neutropenia. The work indicates the difficulties associated with the differential diagnosis of RA, RAS and RAEB with monocytosis, MDS with a dominating change of the type of myelomonocytic dysplasia and CMML proper.