RESUMO
AIM: To examine prognostic potential of the number of bone marrow (BM) blasts and cell karyotype as risk factors of transformation of myelodysplastic syndrome (MDS) in acute myeloblastic leukemia AML. MATERIAL AND METHOD: The analysis of examination was made for 72 patients with primary MDS in the groups formed by number of blasts in BM, karyotype and IPSS variant. MDS was diagnosed by WHO criteria. Transformation into AML was established in blastosis > 20% in peripheral blood and/or BM. The karyotype was studied according to GTG technique. RESULTS: More frequent progression of MDS was seen in patients with blastosis > 10%, unfavourable karyotype and high IPSS risk. The least number of leukemic transformations occurred in karyotype of intermediate prognosis while disease-free survival in patients with karyotype of good prognosis was similar to that of patients with unfavourable karyotype. The number of blasts in BM and IPSS variant appeared to be prognostic markers of duration of leukemia-free survival in one-factor analysis. The multifactorial analysis found out one factor of MDS transformation in AML: number of blasts in BM puncture biopsy. CONCLUSION: Prognostic priority of the number of BM blasts as a risk factor of MDS progression compared to karyotype is explained by biological heterogenicity of MDS.