Chronic Myelogenous Leukemia (CML)

What is chronic myelogenous leukemia (CML)?

Chronic myelogenous leukemia (CML) is a rare type of cancer of the blood cells, starting inside the bone marrow. CML causes an uncontrolled growth of myeloid cells, which make a certain type of white blood cell. The diseased cells build up in the bone marrow and blood. The three phases of CML are:

• Chronic phase: the earliest phase with generally the best response to treatment
• Accelerated phase: a transitional phase when the disease becomes more aggressive
• Blastic phase: a severe, aggressive phase that becomes life-threatening

What are the symptoms of chronic myelogenous leukemia (CML)?

The symptoms of CML are:

• Easy bleeding
• Fatigue
• Fever
• Weight loss
• Loss of appetite
• Pain or fullness below the ribs
• Pale skin
• Bruising
• Night sweats

What causes chronic myelogenous leukemia (CML)?

The cause of CML is related to an abnormal chromosome called the Philadelphia chromosome, i.e. an extra-short chromosome 22, present in the blood cells of 90 percent of people with CML. The Philadelphia chromosome creates a new gene, called BCR-ABL. The BCR-ABL gene contains instructions that tell the abnormal blood cells to produce too much of a protein called tyrosine kinase. Tyrosine kinase promotes cancer by allowing certain blood cells to grow out of control.

How is chronic myelogenous leukemia (CML) diagnosed?

• Clinical examination
• Blood test
• Bone marrow test
• Specialized tests, such as fluorescence in situ hybridization (FISH) analysis and the polymerase chain reaction (PCR) test to analyze blood or bone marrow samples for the presence of the Philadelphia chromosome or the BCR-ABL gene

What treatments are available for chronic myelogenous leukemia (CML)?

The goal of CML treatment is to eliminate the blood cells that contain the abnormal BCR-ABL gene producing the diseased blood cells. Targeted drugs that block the action of tyrosine kinase include:

• Imatinib (Gleevec)
• Dasatinib (Sprycel)
• Nilotinib (Tasigna)
• Bosutinib (Bosulif)
• Ponatinib (Iclusig)

Other treatment options include chemotherapy and biological therapy. The only permanent cure for CML is a bone marrow transplant or stem cell transplant.

Where can I find out more about chronic myelogenous leukemia (CML)?

• Mayo Clinic
• NIH
• Leukemia & Lymphoma Society