Juvenile Myelomonocytic Leukemia

Also known as: JMML, juvenile chronic myeloid leukemia, chronic myelomonocytic leukemia of infancy, infantile monosomy 7 syndrome.

What is juvenile myelomonocytic leukemia?

JMML is a rare, serious chronic form of cancer of the blood in children (frequently boys), aged less than 4 years. On average it affects children around 2 years of age.

What causes juvenile myelomonocytic leukemia?

It appears that though the causes are unknown, sporadic or inherited genetic changes in a particular cell in the bone marrow (stem cell), gives rise to a blood type called an immature monocyte which increases uncontrollably in the bone marrow, eventually preventing the bone marrow producing the other blood cell types (red blood cells, white blood cells and platelets).

Children with Noonan syndrome or neurofibromatosis type 1, are at increased risk of developing JMML.

What are the symptoms of juvenile myelomonocytic leukemia?

Symptoms of JMML can include fever, pale skin (anemia), frequent infections, bruising and abnormal bleeding, a swollen abdomen due to a large spleen and liver, swollen lymph nodes, bone and joint pain, and cough/difficulty breathing.

What are juvenile myelomonocytic leukemia care options?

Chemotherapy and radiation may be used before stem cell transplantation of the bone marrow, the only cure for JMML.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: April 13, 2022 02:38 PM

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