Leukoses acute - a malignant tumour which morphological substrate are blast cells.

The pathogenesis is caused by a proliferation of a clone of tumoral cells with characteristic cytogenetic breakages in an osteal brain, oppression of a normal hemopoiesis, an output of blast cells in a blood, their innidiation in others hemopoietic (a lien, a liver, lymph nodes) and not hemopoietic (a skin, the central nervous system, testicles, easy) organs. Appearance and cytochemical features of blast cells, their genetic features are put in a basis of classifications of acute leukoses.

Intensive studying of cytogenetic and immunologic features of hemoblastoses has led to acceptance of classification by the world organization of public health services in 1999.

The acute erythremic myelosis meets rather seldom. Disease is characterized by a hyperplasia of cells red of some without attributes of a sharp hemolysis. Clinical signs of advance of a hyperchromatic anemia without a reticulocytosis.