Leukemia is a cancer that affects a type of blood cell. It develops in the bone marrow where blood cells are made. Leukemia makes the bone marrow create faulty white blood cells that do not work well. It can make it difficult for your body to fight infections. In addition, leukemia makes the marrow continues to make these blood cells even if there is not enough room for new cells. The leukemia cells build up in the bone marrow and make it difficult for healthy cells to grow.

There are different types of leukemia, but the two types that are most common in children are:

  • Acute lymphoblastic leukemia (ALL)—creates an immature version of a white blood cell called lymphocytes. Will make the immune system weak.
  • Acute myeloid leukemia (AML)—creates an immature version of a myeloid cell which normally develops into white blood cells, red blood cells, or platelets. Can lead to problems with the immune system, anemia, and bleeding problems.
White Blood Cells
White Blood Cells
Copyright © Nucleus Medical Media, Inc.

Leukemia is causes by a problem with genes that determine how bone marrow cells work. It is not clear was causes the changes in the genes.