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 s yndrome is a very uncommon event. We describe a 46-year-old man in who m refractory anemia with excess blasts (RAEB) evolved to a pre-B acute lymphocytic leukemia. Trisomy 8 was one of the cytogenetic abnormalit ies 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 spec ific DNA probe we identified the trisomy 8 to be present in lymphoblas ts, erythroid precursors, myeloblasts, promyelocytes, myelocytes, meta myelocytes, granulocytes, and monocytes. Our case supports the hypothe sis that in MDS the pluripotent precursor cell is affected, and we exa mine the potential role of FISH for the study and follow-up of some he matological diseases.