NCIt definition : A clonal (malignant) hematopoietic disorder with an acute onset, affecting the bone
marrow and the peripheral blood. The malignant cells show minimal differentiation
and are called blasts, either myeloid blasts (myeloblasts) or lymphoid blasts (lymphoblasts).;
Alternative definition : NCI-GLOSS: A rapidly progressing cancer that starts in blood-forming tissue such as
the bone marrow, and causes large numbers of white blood cells to be produced and
enter the blood stream.;