How is BM of AML?

• M:E ratio increased • Blasts > 20% • Erythropoiesis: Erythropoietic cells are reduced. Dyserythropoiesis, megaloblastic features and ring sideroblasts are commonly present. • Immunophenotyping: CD34, CD117, MPO Hypercellular; but sometimes a ‘blood tap’ or ‘dry tap’ occurs due to pancytopenia/ when the marrow is so much packed with leukaemic cells that they cannot be aspirated because the cells are adhesive and enmeshed in reticulin fibres. In such cases, trephine biopsy is indicated.