Chronic eosinophilic leukemia

Chronic eosinophilic leukemia (CEL) is a rare myeloproliferative neoplasm. It causes the body to make too many (overproduce) eosinophils in the bone marrow. Eosinophils are a type of white blood cell that release chemicals in response to some types of infection and during allergic reactions. In chronic eosinophilic leukemia, high numbers of eosinophils are seen in the blood, bone marrow and other tissues.

There is no known cause for chronic eosinophilic leukemia. It hasn’t been linked to a specific chromosome or genetic abnormality.

Chronic eosinophilic leukemia usually progresses slowly and may stay the same for many years. In some people, it may change quickly into acute myelogenous leukemia (AML).


Chronic eosinophilic leukemia may not cause any signs or symptoms in its early stages. It may be found during a routine blood test.

Other health conditions can cause the same symptoms as chronic eosinophilic leukemia. See your doctor if you have these symptoms:

  • tiredness
  • fever
  • cough
  • muscle pain
  • itching
  • diarrhea
  • swelling under the skin around the eyes and lips, in the throat or on the hands and feet


Diagnosing chronic eosinophilic leukemia usually begins with a visit to your family doctor or when a routine blood test suggests a problem with the blood. Your doctor will ask you about any symptoms you have and do a physical exam. Based on this information, your doctor will order tests to check for chronic eosinophilic leukemia or other health problems.

Diagnostic tests include:

  • complete blood count (CBC) to measure the number and quality of white blood cells, red blood cells and platelets
  • blood chemistry tests to check how well certain organs are working
  • bone marrow aspiration and biopsy to determine if you have leukemia or a type of blood disorder

Find out more about these tests and procedures.


Chronic eosinophilic leukemia is rare and can develop differently in different people. It can be stable for many years and then quickly change into AML. As a result, there is no standard treatment plan for chronic eosinophilic leukemia. Your healthcare team will create a treatment plan just for you.

You may be offered one or more of the following treatments.

Drug therapy

Drugs may be used to improve blood cell counts or lessen symptoms. The following drugs may be used to treat chronic eosinophilic leukemia:

  • corticosteroids
  • interferon alfa (Intron A, Wellferon)
  • chemotherapy drugs such as hydroxyurea (Hydrea), cyclophosphamide (Cytoxan, Procytox) and vincristine (Oncovin)

For more information on certain drugs, go to sources of drug information.

Stem cell transplant

A stem cell transplant may be a treatment option for some people with chronic eosinophilic leukemia. Most people with chronic eosinophilic leukemia are older so they may not benefit from a stem cell transplant.


Follow-up after treatment is an important part of cancer care. Follow-up for chronic eosinophilic leukemia is often shared among the cancer specialists (oncologists) or blood specialists (hematologists) and your family doctor. Your healthcare team will work with you to decide on follow-up care to meet your needs.

Don’t wait until your next scheduled appointment to report any new symptoms and symptoms that don’t go away.

Expert review and references