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Acute lymphocytic leukemia (ALL)
Acute lymphocytic leukemia (ALL) 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.
Acute lymphocytic leukemia is also called acute lymphoblastic leukemia.
ALL starts in abnormal lymphoid stem cells. It is called acute because it develops quickly.
ALL is the least common of the 4 major types of leukemia in adults. It is the most common type of leukemia diagnosed in young children, and it occurs more often in boys than girls.
Find out more about ALL.