Osteosarcoma Survivor
Read Mariah's Story

Brain Tumor Survivor
Read Josh's Story

Leukemia Survivor
Read Sydney's Story

Leukemia Survivor
Read Alijah's Story

Wilms Tumor Survivor
Read Rosie's Story

Leukemia Survivor
Read Ryan's Story

Retinoblastoma Survivor
Read Sydney's Story

Chronic Mylegenous Leukemia (CML)

A form of leukemia that rarely strikes in childhood

Chronic mylegenous leukemia (CML) is a disease of the blood and bone marrow. In patients with CML, also called chronic granulocytic leukemia, too many blood stem cells develop into abnormal white blood cells, crowding out healthy cells.  CML is very rare in children, and usually occurs during or after middle age. Most people with CML have a genetic mutation known as the Philadelphia chromosome.


CML might not cause any symptoms at all. However, the following are possible signs of CML:

  • Feeling very tired.
  • Weight loss for unknown reason.
  • Night sweats.
  • Fever.
  • Pain or feeling of fullness below the ribs on the left side.


If symptoms suggest a child may have CML, the next step is to conduct tests which will give doctors the information needed for a diagnosis. These tests may include:

  • Blood test: A sample of blood allows doctors to perform several different tests, such as a complete blood count (CBC), blood chemistry studies, and cytogenetic analysis.
  • Bone marrow aspiration and biopsy: For this procedure, hollow needles are inserted into each hipbone. Samples are taken of blood, bone marrow, and bone, and examined under a microscope for signs of cancer.

The treatment path for CML and chances of recovery from the disease depend on a variety of factors, including:

  • The patient’s age.
  • The patient’s general health.
  • The amount of blasts in the blood or bone marrow.
  • The size of the spleen at diagnosis.
  • The phase of CML.


After CML is diagnosed, doctors will make a determination of how far the disease has spread. This process is called “staging.” In order to stage a case of CML, doctors look at the number of blast cells in the blood and bone marrow and the severity of symptoms. This information is used to sort the individual patient’s disease into one of three phases:

  • Chronic phase: In chronic phase CML, fewer than 10% of the cells in the blood and bone marrow are blast cells.
  • Accelerated phase: In accelerated phase CML, between 10% to 19% of the cells in the blood and bone marrow are blast cells.
  • Blastic phase: In blastic phase CML,  20% or more of the cells in the blood and bone marrow are blast cells. When tiredness, fever, and an enlarged spleen occur during blastic phase, it is called blast crisis.

Sometimes a patient with CML will go into remission after treatment, only to experience a return of the disease. When the number of blast cells increases after remission, it is called relapsed CML.


There are many different treatments for CML. Patients might choose to enroll in a clinical trial, or may choose a standard therapy. There are six standard therapies for the disease.

  • Targeted therapy: Normal cells aren’t harmed by the drugs or other substances that attack cancer cells in this therapy, which often involves using tyrosine kinase inhibitors.
  • Chemotherapy: Taken either by mouth or by injection, the anti-cancer drugs used in this therapy may kill cancer cells or may stop them from dividing. 
  • Biologic therapy: Also called biotherapy or immunotherapy, this treatment uses the patient’s immune system to fight cancer with help from substances made by the body or in a laboratory.
  • High-dose chemotherapy with blood or bone and marrow transplant (BMT, also known as stem cell transplant): Stem cells are removed from the blood or bone marrow of the patient (or a donor) and stored while the patient undergoes high-dose chemotherapy. After chemo, the stem cells are given to the patient through an infusion so they can restore the body’s blood cells.
  • Donor lymphocyte infusion (DLI): This treatment is used after a blood and marrow transplant and requires blood from the donor. Lymphocytes (a type of white blood cell) from the donor’s blood are given to the patient in an infusion.  After sensing the cancer cells do not belong to the body, the lymphocytes attack and destroy them.
  • Surgery: Surgeons may remove the spleen in a procedure called a splenectomy.

Treatment by stage

Chronic phase CML

  • Targeted therapy with a tyrosine kinase inhibitor.
  • High-dose chemo with BMT.
  • Biologic therapy (interferon), with or without chemotherapy.
  • Chemotherapy.
  • Splenectomy.
  • A clinical trial of lower-dose chemo with BMT.
  • A clinical trial of a new treatment.

Accelerated phase CML

  • BMT.
  • Targeted therapy with a tyrosine kinase inhibitor.
  • Biologic therapy (interferon), with or without chemotherapy.
  • High-dose chemotherapy.
  • Chemotherapy.
  • Transfusion therapy to replace red blood cells, platelets, and sometimes white blood cells, to relieve symptoms and improve quality of life.
  • A clinical trial of a new treatment.

Blastic phase CML

  • Targeted therapy with a tyrosine kinase inhibitor.
  • Chemotherapy using one or more drugs.
  • High-dose chemotherapy.
  • BMT.
  • Chemotherapy as palliative therapy to relieve symptoms and improve quality of life.
  • A clinical trial of a new treatment.

Relapsed CML

  • Targeted therapy with a tyrosine kinase inhibitor.
  • BMT.
  • Donor lymphocyte infusion (DLI).
  • Biologic therapy (interferon).
  • A clinical trial of more types of higher doses of targeted therapy and donor stem cell transplant.

Leading the way to a cure

Researchers in the University of Minnesota Pediatric Leukemia Program work to provide treatment programs that will improve survival rates for high-risk or relapsed patients with leukemia. Children’s Cancer Research Fund’s relationship with the University’s Masonic Cancer Center supports this work by providing resources to help with pilot studies and support for clinical trials.

For more information on our work with leukemia, visit our Leukemia Research page.
This information is displayed with permission of the University of Minnesota Cancer Center. For more information about this disease or to review active clinical trials, please visit the website of the Cancer Center.

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