Also called Chronic Myeloid Leukemia, Chronic Granulocytic Leukemia
CML is a rare form of blood cancer, with an estimated 5,430 Americans being diagnosed with the disease and 610 dying from it in 2012.
Our bone marrow produces millions of blasts, which are immature white blood cells that go on to form one of a range of white blood cells, helping to fight infection. These include granulocytes, a term which describes 3 different types of white blood cell. If a person has CML, their bone marrow produces too many granulocytes, which, if the disease is allowed to progress, flood the bloodstream, pushing out healthy cells and affecting body function.
More than 90% of CML cases are caused by one single, genetic mutation, the Philadelphia Chromosome, although other causes include exposure to chemicals and previous radiotherapy for illnesses such as Hodgkin’s Disease.
It can be hard to cope when a chronic disease reaches the stage where it must be treated. This is why the Bone Marrow Transplant Unit of Hospital Angeles Lomas offers an obligation-free, complimentary consultation to help you to choose the best treatment.
The disease progresses through three phases: chronic, accelerated and blast.
The chronic phase can last for months or even years, and during this period there may be few or no symptoms. The disease is usually picked up at this stage through routine blood tests.
In the Accelerated phase the leukemia cells grow more rapidly and symptoms can include fever, bone pain and a swollen spleen.
If the CML is not treated it will result in the blast phase. At this point the production of mutated and immature granulocytes is unbearably high, resulting in bone marrow failure. Symptoms at this point are similar to those of AML.
Because a patient in blast phase of CML has lower numbers of healthy white cells, to fight infection, red cells, to carry oxygen around the body and platelets, to control bleeding in the body, it can result in the following symptoms:
- Anemia; due to the lack of red blood cells in the blood, oxygen is not carried around the body.
- Fever and infections due to the lack of infection-fighting healthy white blood cells.
- Bruising, blood blisters or red spots caused by low platelet levels (platelets help blood to clot).
- A rash
- Pressure under the ribs, caused by a swollen spleen
Treatment and Diagnosis
A physical examination will show whether your spleen is swollen, whilst a blood test will reveal high levels of white blood cells and platelets in the blood, as well as the odd blast. A bone marrow biopsy will show the function of the bone marrow and test for genetic factors such as the Philadelphia Chromosome.
Treatment will vary according to the general health of the patient and the phase of the disease. In the chronic phase an oral drug can be given to control the disease, and chemotherapy can be used to reduce a high white blood count.
In the blast phase, the condition is difficult to treat, because of the high level of leukemia cells within the blood at this point. The treatment is similar to that for acute leukemia.
CML and BMT
The only known cure for CML is a bone marrow transplant or stem cell transplant. Because the cancer is in the bone marrow, only an allogeneic or cord blood transplant can be used for CML. Chemotherapy will be used to destroy all of the existing bone marrow, then healthy donated stem cells are introduced to the body, with the hope that the new stem cells will reproduce to form healthy, leukemia-free bone marrow. If the patient does relapse after the transplant, the donor cells used in the initial transplant can be used again to fight the leukemia.
For many patients, bone marrow transplant will offer the best chances of achieving remission and staying in remission. Usually before a transplant, high intensity chemotherapy is given to kill off any remaining abnormal bone marrow. This is known as a myeloablative transplant. If the patient is considered to be in weaker health, such intensive treatment is considered too risky so lower intensity chemotherapy, known as non-myeloablative treatment, is a safer option.
Making a Decision
It is important to remember that the treatment offered by your own hospital may be limited by resources, budget and ability. Researching other options, such as private hospitals and clinical trials will enable you to make an informed decision on the courses of treatment that you could have, not just the ones available to you in your local hospital.
Whilst bone marrow and cord blood transplants do carry risks, they are also the only known cure for CML. Your doctor here will help you to weigh the risks against the benefits to decide the best course of treatment for you.
If you would like a free consultation with a medical professional then please don’t hesitate to contact us by filling out an inquiry form.