Introduction
Acute megakaryoblastic leukemia (AMKL) is a subtype of acute myeloid leukemia (French-American-British classification AML-M7) which is defined as 50% or more of total blast cells in a bone marrow sample being attributed to megakaryoblasts1. As with other subtypes of acute myeloid leukemia (AML), the total blasts of more than 20% of all nucleated cells in the peripheral blood film and bone marrow also applies to AMKL. AMKL was first described by Von Boros, et al in 1931. AMKL may occur as de novo, or secondary to a myelodysplastic syndrome (MDS) or myeloproliferative neoplasm (MPN). AMKL shows a bimodal age distribution; being common in children aged 1-3 and elderly adults. Down syndrome (DS) individuals have a 500-fold increase in contracting AMKL, and they have a better prognosis as compared to non-DS individuals2. There is also an association between mediastinal germ cell tumours (GCT) and AMKL in young male children with many of them being diagnosed with AMKL a few months later3. AMKL is known to be associated with extensive myelofibrosis resulting in a frequent dry bone marrow aspiration. This disease demonstrates a poor prognosis with the median survival of less than 6 months from diagnosis4. Here, we report an unusual case of transformation of myelodysplastic syndrome to acute megakaryoblastic leukemia in a middle-aged male who followed an aggressive course of illness.