Acute leukemia

With acute leukemia, leuk- refers to white blood cells, and -emia refers to the blood, so in acute leukemia, there’s uncontrolled proliferation of partially developed white blood cells, also called blast cells, which build up in the blood over a short period of time.

Although leukemia means cancer white blood cells, it can also be used to refer to cancer of any of the blood cells, including red blood cells and platelets.

Acute leukemia can be broadly classified into acute myeloid leukemia, or AML; and acute lymphoblastic leukemia, ALL.

AML is more common in old age, where as ALL is more common in children. In both cases, accumulation of blast cells interferes with the development and function of healthy white blood cells, platelets, and red blood cells.

Now, every blood cell starts its life in the bone marrow as a hematopoietic stem cell. Hematopoietic stem cells are multipotent -- meaning that they can give rise to both myeloblasts, which are precursors of myeloid blood cells, and lymphoblasts, which are precursors of lymphoid blood cells.

These lymphoblasts can be pre-B cells, which develop into B lymphocytes; or pre-T cells, which develop into T lymphocytes.

If a hematopoietic stem cell develops into a myeloid cell, it’ll mature into an erythrocyte -- or a red blood cell, a thrombocyte -- or a platelet, or a leukocyte -- or a white blood cell, like a monocyte or granulocyte.

Granulocytes are cells with tiny granules inside of them -- they include neutrophils, basophils, and eosinophils.

If a hematopoietic stem cell develops into a lymphoid cell, on the other hand, it’ll mature into some other kind of leukocyte: a T cell, a B cell, or a natural killer cell, which are referred to as lymphocytes.