[Transformation of myelodysplastic syndrome to acute lymphoblastic leukemia: 2 new cases]

Myelodysplastic syndromes (MDS) are clonal disorders of hematopoietic stem cells, with a variable risk of transformation to acute myeloid leukemia. Progression into acute lymphoblastic leukemia (ALL) is an extremely rare event, with very few cases published in children. In this report, we describe two cases of myelodysplastic syndromes that progressed to ALL. Moreover, we review previously reported cases of MDS transformation to acute lymphoblastic leukemia in the pediatric population whose prognosis seems to be similar to that for adults.