Understanding Chronic Myeloid Leukemia: Causes, Symptoms, and Treatment

The choice of treatment for CML depends on factors like the phase of the cancer and your age, says the American Cancer Society.

Chronic Phase Treatment Options

The main treatment for the chronic phase of CML is a type of targeted drug called a tyrosine kinase inhibitor (TKI). This medicine blocks BCR-ABL, which is a protein called a tyrosine kinase.

Examples of TKIs are:

Your doctor will do routine tests of your blood counts and your bone marrow to check your response to the treatment. Up to 70 percent of people have a complete cytogenic response — meaning that less than 1 percent of the cells in the bone marrow contain the Philadelphia chromosome — within one year after starting imatinib, according to the American Cancer Society.

If the cancer doesn’t respond to a TKI or the drug stops working, you may need to switch to a new leukemia treatment. That could be another TKI, a chemotherapy, the immunotherapy drug interferon, or a stem cell transplant.

Accelerated Phase Treatment Options

Which treatment you get once your cancer enters this phase depends on the treatment you received in the chronic phase. If you haven’t had treatment yet, you’ll likely get a TKI. If you’ve already been on a TKI, your doctor might bump up the dose or switch you to another medication in this class. Although TKIs still work in the accelerated phase, they aren’t as likely to produce a long-term response, says the American Cancer Society.

An allogeneic stem cell transplant is an option if you’re young and healthy enough to undergo the procedure. You’ll receive high doses of chemotherapy to kill the abnormal cells in your bone marrow. Because the chemo also destroys healthy blood cells, you’ll then get healthy blood-forming stem cells from a donor to replace them.

An allogeneic stem cell transplant is the only way to cure CML, but it is a difficult treatment that can have life-threatening side effects, according to the American Cancer Society.

Blast Phase Treatment Options

Some people in the blast phase who haven’t received treatment yet may benefit from high-dose imatinib, but it doesn’t work as well as it does in earlier phases. Newer TKIs like dasatinib, nilotinib, and bosutinib may be more effective in the blast phase, according to the American Cancer Society.

By now, the cancer cells have become more abnormal. They sometimes act like acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL). The same chemotherapy drugs that are used to treat AML or ALL may help put CML into remission in a small percentage of people.

An allogeneic stem cell transplant is the only possible cure, but it works for just a small percentage of people in the blast phase. Another option is to enroll in a clinical trial of a new CML treatment.

Clinical Trials

Clinical trials are studies that test out the safety and effectiveness of new CML medications and drug combinations. You can enroll in one of these trials during any phase of CML. Signing up could give you access to a cutting-edge therapy before it’s available to the public. What researchers learn from clinical trials helps future generations of people with CML.

If you’re interested in joining a clinical trial, ask your hematologist-oncologist if any CML studies are a good fit for you.