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What is juvenile myelomonocytic leukemia (JMML)?

Juvenile myelomonocytic leukemia (JMML) is a rare type of blood cancer that occurs when bone marrow production of white blood cells becomes severely disregulated. In children with JMML, the bone marrow — the soft, spongy center of the bones responsible for creating blood cells — produces immature white blood cells that grow too rapidly and keep reproducing even when they run out of space. This crowds out healthy bone marrow cells and can lead to symptoms such as infections, anemia, and bleeding. Currently, the only cure for JMML is stem cell transplant.

Our approach to JMML treatment at Dana-Farber/Boston Children's

Patients with JMML are treated at Dana-Farber/Boston Children's Cancer and Blood Disorders Center through the Leukemia Program, one of the top programs worldwide for pediatric leukemia. We also have one of the largest and most experienced pediatric stem cell transplant programs in the U.S.

Find in-depth details on JMML on the Dana-Farber/Boston Children’s website, including answers to:

  • How is JMML diagnosed?
  • What is the best treatment for JMML?
  • What is the latest research on JMML?
  • What is the long-term outlook for children with JMML?