9867/3 FAB M4


Tumours of haematopoietic and lymphoid tissues
ICD-O-3 topography code: C42 and C77
ICD10: C92.5

/span>cute myelomonocytic leukaemia is an acute leukaemia characterized by the proliferation of both neutrophil and monocyte precursors. The PB or BM has ≥20% blasts (including promonocytes); neutro?phils and their precursors and monocytes and their precursors each comprise at least 20% of BM cells. This arbitrary minimal limit of 20% monocytes and their precursors distinguishes acute myelo?monocytic leukaemia from cases of AML with or without maturation in which some monocytes may be present. A high number (usually ≥5x109/L) of monocytic cells may be present in the PB.