If you have chronic myeloid leukemia, there are several treatment options available. These include targeted therapies, chemotherapy, and bone marrow transplants.
About Chronic Myeloid Leukemia
Chronic myeloid leukemia is sometimes known as chronic myelogenous leukemia, or simply CML. This is a specific kind of cancer that begins in the blood-forming cells in the bone marrow. It’s thought to be caused by a gene that makes too much of a protein called tyrosine kinase. Symptoms develop slowly so many people don’t know they have CML for a long time. It’s often diagnosed during blood work tests done for other reasons.
Phases of CML
CML has three phases. These phases are based on how many cancer cells are present.
- The chronic phase is the first phase of CML, when there are fewer cancer cells and they’re growing slowly.
- CML progresses to the accelerated phase if treatment isn’t sought or is unsuccessful. During this phase, there are more cancer cells and they’re growing more quickly.
- In the blast crisis phase, the cancer cells are growing rapidly. This leaves little room for healthy cells, which is why it’s considered the most dangerous phase.
Treatment depends on the phase of cancer, and other factors like age and overall health. The standard course of treatment begins with targeted therapy, which involves oral medications called tyrosine kinase inhibitors or TKIs. These drugs specifically target tyrosine kinase and block its action. This slows or stops the growth of cancer cells.
The drugs imatinib (Gleevec), nilotinib (Tasigna), and bosutinib (Bosulif) are three of the most widely known TKIs. These drugs are highly effective, and many people go into remission for years on this type of therapy. Side effects are usually mild and are far outweighed by their benefits. Some side effects may include:
- fluid buildup
- lowered white blood cell and/or platelet counts
In some cases, chemotherapy may be prescribed along with a TKI. This may help lower the white blood cell count, killing off many of the diseased cells. As the TKI stops the cancer cells from coming back, room is left for healthy cells to grow.
If one type of TKI fails to work, or stops being effective, then another can be prescribed. If none of the TKIs are effective, then the cancer progresses to one of the two later phases: accelerated or blast crisis. A bone marrow transplant is likely necessary if this occurs. If possible, during blast crisis, TKIs and/or chemotherapy will be used to bring the cancer back to the chronic phase before the transplant.
In a transplant, the cancerous cells are replaced by healthy bone marrow. The person’s immune system cells are also replaced by the donor’s, which prevents new cancer cells from growing. This is the only treatment that can result in a cure for CML. About 70 percent of patients who receive a transplant are cured. Success rates are higher when the donor is a sibling or other close relative. Because more parents are choosing to store umbilical cord blood, some people may be able to receive transplants of their own stem cells. This is even better than using a donor who is a relative because the cells are an exact match.
Although transplants can result in a complete cure, it isn’t the first course of treatment. Transplants are demanding on the body and can result in serious complications.
Overall prognoses for those with CML are good, and are only getting better as new and improved treatments are being developed. Large-scale research studies are helping find new and effective TKIs, while websites are helping connect potential donors with those who need bone marrow transplants.