Leukemia

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Chronic myelogenous leukemia (CML)

Chronic myelogenous leukemia (CML) is a cancer that starts in blood stem cells. Stem cells are basic cells that develop into different types of cells that have different jobs.

As the stem cells of the blood develop, they become blast cells (blasts), which are immature blood cells. In leukemia, there is an overproduction of blast cells. These blast cells develop abnormally and don’t develop into mature blood cells. Over time, the blast cells crowd out normal blood cells so that they can’t do their jobs. When leukemia is diagnosed, these blast cells may be called leukemia cells.

CML starts in abnormal myeloid stem cells. It is called chronic because it develops slowly. The abnormal myeloid stem cells develop into cancerous (malignant) granulocytes.

CML is one of the less common types of leukemia in adults. It rarely develops in children.

Find out more about CML.

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