Chronic myeloid leukemia (CML)

Chronic myeloid leukemia (CML) is a cancer of the bone marrow. It’s caused by the presence of an abnormal chromosome in bone marrow cells called the Philadelphia chromosome. Chromosomes carry instructions that tell the body how to function, but when the Philadelphia chromosome is present, your body’s bone marrow makes too many white blood cells. At this time, doctors don’t know what causes the Philadelphia chromosome to appear in the body.

For CML, doctors use an allogeneic transplant, meaning the donated cells come from someone else. These healthy blood-forming cells can come from:

• A family member
• An unrelated donor
• Umbilical cord blood

Although each person’s journey is unique, bone marrow transplantation for chronic myeloid leukemia typically follows a series of distinct phases. From initial therapy to the infusion of donor cells and ongoing recovery, here’s how the transplant process generally works.

• Preparation: You’ll begin with chemotherapy (and sometimes radiation) to destroy the unhealthy marrow. This step, called conditioning therapy, makes room for new, healthy blood-forming cells.
• Transplant: Next, healthy donor cells are delivered through an intravenous (IV) catheter, often referred to as a stem cell infusion. These cells travel to the inside of your bones and begin producing new blood cells.
• Recovery: Full recovery can take several months to a year. From the start of conditioning to leaving the hospital can take weeks to months. You’ll then spend additional time recovering near the transplant center and at home. During this period, your transplant team carefully monitors you, helping prevent and manage any side effects or complications.

If you or your child are diagnosed with CML, you should see a transplant doctor right away. Young patients who have a closely matched donor and get a transplant soon after diagnosis may have a better chance for a cure. Most patients with CML take medicines called TKIs (tyrosine kinase inhibitors). These medicines can control CML for months or years but may lose their effectiveness over time. You should see a transplant doctor immediately if:

• The CML doesn’t get better with standard treatment.
• The CML gets worse despite treatment with TKIs.
• You or your child can’t take TKIs because of severe side effects or an allergy.
• The CML is in the accelerated or blast phase.

Even if a transplant isn’t needed right away, it’s still important to schedule an appointment with a transplant doctor. Many CML patients depend on blood transfusions, but repeated transfusions can reduce the likelihood that a future transplant will be successful. For this reason, most doctors recommend meeting with a transplant specialist as soon as CML is diagnosed.

Scheduling an appointment with a doctor to discuss your CML diagnosis is the first step to finding a cure. At the first appointment, the transplant doctor will:

• Review your or your child’s medical history
• Talk with you about CML treatment options
• Discuss the risks and benefits of BMT transplant
• Recommend the best time for you or your child to get a transplant and prepare for treatment
• Start a donor search

Patients that come from ethnically diverse backgrounds will often have a harder time finding a matching bone marrow donor. This is because of genes called human leukocyte antigens (HLAs), which are the codes inside your body doctors use to help find a match. HLAs are inherited, which means it will be easier to find a match using a patient and donor that share the same ancestry.

Unfortunately, not all ethnicities are equally represented on the registry. 

Learn more about the importance of diversity

Ask questions so you can best understand the treatment options available for your chronic myeloid leukemia. Questions you may want to ask include:

• What are the chances of curing CML or going into long-term remission with or without a transplant?
• Does the phase of CML make a difference on how well transplant might work?
• Does my or my child’s current health or age affect how well a bone marrow or blood stem cell transplant might work?
• What are the possible side effects of transplant? How can they be reduced?
• How might my or my child’s quality of life change over time due to CML, with or without transplant?

By asking these questions, you can better understand your options and plan the next steps in your treatment journey.

Learn more about planning for transplant