Acute Leukemia

Leukemia is a cancer of the blood, which is characterised by rapid, uncontrolled growth of abnormal blood cells. This uncontrolled growth is the result of mutations in the DNA of blood stem cells in the bone marrow. In a normal situation, these stem cells develop into myeloid or lymphoid cells. While myeloid cells eventually develop into red blood cells, platelets, and certain types of white blood cells (basophils, eosinophils, and neutrophils), lymphoid cells develop into lymphocytes or natural killer cells, two specific types of white blood cells.

Mutations in the DNA of these lymphoid or myeloid stem cells give rise to immature leukemia cells that are unable to fulfill the normal functions of blood cells. As a result of their rapid growth, these leukemia cells take over the space inside of the bone marrow, crowding out the healthy cells responsible for the production of normal blood cells.

Leukemias are classified based on the speed by which the disease progresses and the involved blood stem cell. In the case of acute leukemia, the leukemic cells divide very rapidly, and patients will develop symptoms very fast. Given this fast progression, immediate initiation of therapy is necessary in case of acute leukemia. 

When leukemia cells arise from myeloid stem cells, the disease is referred to as acute myeloid leukemia (AML). In contrast, when lymphoid cells are the cell of origin, the disease is called acute lymphoblastic leukemia (ALL).