Mechanisms of development of acute leukemia – pathogenesis
Acute leukemias result from the clonal neoplastic proliferation of blast cells, which are characterized by blockade of differentiation into more mature blood cells and the ability for virtually unlimited division. In acute leukemia, the tumor is a clone – the offspring of a single malignant cell. Accumulating in the bone marrow, leukemic blasts displace normal hematopoiesis cells, which ultimately leads to symptoms of the disease.
In laboratory studies of acute leukemia, about 1011 blast cells are found in the patient’s body, with the development of clinical symptoms – 1012 blasts (approximately one kilogram).
Leukemia cells circulate in the blood and can cause damage to other organs and tissues (the frequency and nature of the lesion depends on the variant of acute leukemia). Unlike chronic leukemias, which have the phenotypic and biological characteristics of more mature cells, acute leukemia develops and is biologically similar to primitive hematopoietic progenitor cells. The phenotypic heterogeneity of leukemic cells suggests that acute leukemia (AL) can occur at various stages of differentiation.