Juvenile myelomonocytic leukemia is a childhood disease in which too many myelocytes and monocytes (immature white blood cells) are made in the bone marrow.
Juvenile myelomonocytic leukemia (JMML) is a rare childhood cancer that occurs more often in children younger than 2 years. Children who have neurofibromatosis type 1 and males have an increased risk of juvenile myelomonocytic leukemia.
For more information from the National Cancer Institute about chronic lymphocytic leukemia, see the following:
Leukemia Home Page
What You Need to Know About™ Leukemia
Drugs Approved for Chronic Lymphocytic Leukemia
Targeted Cancer Therapies
Understanding Cancer Series: Targeted Therapies
Biological Therapies for Cancer: Questions and Answers
For general cancer information and other resources from the National Cancer Institute, see the following:
What You Need ...
In JMML, the body tells too many blood stem cells to become two types of white blood cells called myelocytes and monocytes. Some of these blood stem cells never become mature white blood cells. These immature white blood cells are called blasts. Over time, the myelocytes, monocytes, and blasts crowd out the red blood cells and platelets in the bone marrow. When this happens, infection, anemia, or easy bleeding may occur.
Possible signs of juvenile myelomonocytic leukemia include fever, feeling very tired, and weight loss.
These and other symptoms may be caused by JMML. Other conditions may cause the same symptoms. Check with your doctor if you have any of the following problems: