What Type of Leukemia Is Most Common in Childhood?

Medically Reviewed on 12/21/2022
What Type of Leukemia Is Most Common in Childhood
The most common type of leukemia in children is acute lymphocytic leukemia (ALL)

Acute lymphocytic leukemia (ALL) is the most common type of childhood leukemia, followed by acute myeloid leukemia (AML). Chronic leukemias are rarely seen in children.

Leukemias are cancers that start in the blood cells and mostly affect children and teens (accounting for one out of three cancers).

What are the different types of childhood leukemia?

Leukemia is categorized into different types based on whether they are acute (fast-growing) or chronic (slow-growing) and the type of cells in which cancer starts:

  • Myeloid leukemia (leukemia starts in myeloid cells)
  • Lymphoid leukemia (leukemia starts in lymphoid cells)

Acute leukemias

Acute leukemias progress quickly and require aggressive and immediate treatment. Acute leukemia is further categorized into the following:

  • Acute lymphocytic (lymphoblastic) leukemia (ALL): Typically start in early forms of white blood cells (lymphocytes) and accounts for 3 out of 4 childhood leukemias
  • Acute myeloid leukemia (AML): Can disrupt normal white blood cells, red blood cells, and platelet production; also called acute myelogenous leukemia, acute myelocytic leukemia, or acute nonlymphocytic leukemia
  • Acute undifferentiated leukemias: A rare type of acute leukemia that does not have lymphoid or myeloid cell-specific markers

Chronic leukemias

Chronic leukemias tend to grow slowly and are harder to cure. Chronic leukemias can be further divided into the following:

Juvenile myelomonocytic leukemia (JMML)

JMML is a rare type of leukemia (neither acute nor chronic) that starts in myeloid cells but usually does not grow as fast as AML or as slowly as CML. It is most often found in young children, and the average age at diagnosis is 2 years.

How does childhood leukemia start?

Leukemia typically starts in the bone marrow and can spread to the bloodstream. Certain types of leukemia can spread to other parts of the body, including the lymph nodes, liver, spleen, central nervous system (brain and spinal cord), and testicles.

Unlike other cancers, leukemia does not form tumors or masses. Leukemia generally affects white blood cells (WBCs) and causes rapid uncontrollable growth of WBCs. WBCs are produced by the bone marrow and help prevent infections, acting as the internal defense system of the body. 

However, in people with leukemia, the bone marrow creates an abnormally large number of abnormal white blood cells that do not function correctly and cause serious medical complications.

What can trigger leukemia to occur?

Some of the known risk factors for childhood leukemia include:

  • Family history: Having a sibling with leukemia
  • Genetic disorders:
    • Down syndrome (trisomy 21): Children with an extra copy of chromosome 21 are more likely to develop acute lymphocytic (lymphoblastic) leukemia (ALL) or acute myeloid leukemia (AML).
    • Li-Fraumeni syndrome: This is a rare inherited condition caused by a change in the TP53 gene and comes with a higher risk of leukemia.
  • Inherited immune system problems:
  • Lifestyle factors: Research studies suggest that excessive alcohol consumption during pregnancy may increase the risk of leukemia in the child.
  • Environmental factors: Radiation and certain chemicals can increase the risk of leukemia.
  • Exposure to chemotherapy: Children treated with chemotherapy drugs (for other cancers) have a higher risk of developing AML.
  • Immune system suppression: Children undergoing intensive treatment to suppress the immune system (for organ transplants) have an increased risk of certain cancers, such as lymphoma and ALL.

Other factors that are controversially linked to childhood leukemia include:

  • Exposure to electromagnetic fields
  • Living near a nuclear power plant
  • Viral infections early in life
  • Age of the mother at the time of childbirth
  • Fetal exposure to hormones (diethylstilbestrol)
  • Paternal smoking history
  • Paternal occupational exposure to toxins, chemicals, and solvents
  • Chemical contamination of groundwater


What is leukemia? See Answer

What are the symptoms of leukemia in children?

A child with leukemia may present with the following symptoms:

How is childhood leukemia treated?

Treatment of acute leukemia generally involves the use of chemotherapy and radiation therapy to destroy the leukemia cells:

  • Radiation therapy: High-energy X-rays are used to kill cancer cells.
  • Chemotherapy: Anticancer medications are administered intravenously (IV) or orally.
  • Targeted therapy: Specific drugs are used to target and attack cancer cells without damaging normal cells.
  • Stem cell transplants: Healthy stem cells (young blood cells) are transferred into the body.
  • Blood transfusion: May be done for low blood counts.
  • Antibiotics: May be prescribed to treat any infections.

What are the potential complications of childhood leukemia?

Potential complications of leukemia may include:

  • Serious infections
  • Severe bleeding (hemorrhage)
  • Blood thickening (due to large numbers of leukemia cells)
  • Relapse of the leukemia
  • Change to a more aggressive cancer type
  • Growth of other cancers
  • Heart and lung problems
  • Learning problems
  • Slow growth and development
  • Osteoporosis (thinning of bones)

What is the life expectancy of a child with leukemia?

The prognosis of childhood leukemia depends on certain factors, such as the age at diagnosis, gender, chromosomal changes, type and extent of the disease, and the initial response to treatment.

With early diagnosis and appropriate treatment, the 5-year survival rate of children aged 0-14 years diagnosed with acute lymphocytic leukemia (ALL) has increased to 90%. Children younger than 15 years with acute myeloid leukemia (AML) have a 5-year survival rate of 68%.

Medically Reviewed on 12/21/2022
Image Source: iStock image

Childhood Leukemia. https://www.webmd.com/cancer/lymphoma/childhood-leukemia-symptoms-treatments

Leukemia in Children. https://www.cancer.org/cancer/leukemia-in-children.html

Leukemia in Children. https://www.cedars-sinai.org/health-library/diseases-and-conditions---pediatrics/l/leukemia-in-children.html

Leukemia. https://kidshealth.org/en/parents/cancer-leukemia.html