Progression of a myelodysplastic syndrome to pre-B acute lymphoblastic leukemia: a case report and cell lineage study.

The evolution of acute lymphoblastic leukemia from a myelodysplastic syndrome is a very uncommon event. We describe a 46-year-old man in whom refractory anemia with excess blasts (RAEB) evolved to a pre-B acute lymphocytic leukemia. Trisomy 8 was one of the cytogenetic abnormalities in the dysplastic clone and was detected in both peripheral blood and bone marrow smears of interphase cells by the fluorescence in situ hybridization (FISH) technique. Using a chromosome 8 centromeric specific DNA probe we identified the trisomy 8 to be present in lymphoblasts, erythroid precursors, myeloblasts, promyelocytes, myelocytes, metamyelocytes, granulocytes, and monocytes. Our case supports the hypothesis that in MDS the pluripotent precursor cell is affected, and we examine the potential role of FISH for the study and follow-up of some hematological diseases.