Childhood leukemia

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If childhood leukemia spreads

Leukemia starts in the bone marrow, where blasts (immature blood cells) develop into red blood cells, white blood cells and platelets. Once leukemia is diagnosed, blasts can also be called leukemia cells. The leukemia cells can spread wherever the blood travels. As a result, leukemia is already in different parts of the body when it is found.

In the bone marrow, the red blood cells and platelets cannot work properly because they are crowded out by too many leukemia cells. When leukemia cells spread to other parts of the body, they don’t usually form solid tumours in other organs. But the buildup of abnormal cells in the blood affects the organs.

Understanding how a type of cancer usually grows and spreads helps the healthcare team plan your child’s treatment and future care. Leukemia cells can collect in the following organs:

  • lymph nodes
  • liver
  • spleen
  • testicles
  • skin
  • gums
  • brain and spinal cord (called the central nervous system, or CNS)


A teenaged girl sitting on her bed I was in total shock when I heard the diagnosis of cancer. Cancer to me was an adult’s disease. Being a 13-year-old teenager, it certainly wasn’t even on my radar.

Read Sabrina's story

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