Transformation of childhood MDS-refractory anemia to acute lymphoblastic leukemia.

Myelodysplastic syndromes (MDS) are clonal disorders of hematopoietic stem cell. Patients have a deteriorating course with about 30% evolving into acute leukemias usually of the myeloid phenotype. Evolution into acute lymphoblastic leukemia is a rare and intriguing phenomenon seen in far less than 1% of adult cases, and extremely rare in pediatric population. We report a case of childhood MDS-refractory anemia transforming into acute lymphoblastic leukemia after an interval of 21 months since presentation and being on cyclosporine therapy for 9.5 months. The case raises further questions about the biology of MDS and the potential role of cyclosporine in leukemic transformation.