What is Acute Lymphoblastic Leukemia (ALL)?

Leukemia is cancer of the blood cells. In a healthy child, bone marrow makes white blood cells, red blood cells and platelets. White blood cells fight infection, red blood cells carry oxygen throughout the body and platelets help the blood clot. When a child has leukemia bone marrow makes abnormal white blood cells. These abnormal cells grow quickly and do not stop growing like normal white blood cells. They don’t fight infection like normal blood cells and eventually overcrowd normal cells we need. This leads to problems such as: anemia (low iron in the blood), bleeding and infections. Acute Lymphoblastic Leukemia (ALL) is the most common type of childhood leukemia, usually affecting children between 2 and 5 years old. ALL causes the body to produce huge numbers of white blood cells (more than the body needs) which crowd other healthy cells. This type of leukemia has many subtypes which explain why treatments can vary. ALL is the most successfully treated type of childhood leukemia.

What are the causes?

  • DNA (genetic code) mutations cause blood cell production and development problems. However, it is not clear why these mutations occur.

What are the risk factors?

  • Previous cancer treatment
  • Exposure to radiation
  • Genetic Disorders (like Down syndrome)
  • Sibling with ALL Note: many children that develop ALL will not have any known risk factors

What can I do?

  • Tell your child’s doctor about any changes in your child’s behavior and/or symptoms
  • Follow treatment instructions carefully
  • Find out if your child is a candidate for a clinical trial, which may offer new drug treatments

Find more information about our pediatric hematology/oncology experts or to make an appointment, call the Jonathan Jaques Children's Cancer Center at Miller Children's at (562) 728-5000.

It is important to remember the health information found on this Web site is for reference only not intended to replace the advice and guidance of your health care provider. Always seek the advice of your physician with any questions you may have regarding a medical condition. If you think you may have a true medical emergency, call 911 immediately.


  • Fever
  • Bleeding from the gums
  • Frequent or severe nosebleeds
  • Shortness of breath
  • Pale skin
  • Loss of appetite
  • Weight loss
  • Fatigue
  • Bone pain
  • Frequent infections
  • “Lumps” around the neck, underarms, stomach or groin


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