What is Chronic Myeloid Leukemia?
Leukemia is a cancer that forms in the blood or blood-forming tissues. There are various types of leukemia, and treatment for each one is different. Chronic leukemias develop slower than acute leukemias, but can be just as life-threatening.
Chronic myelogenous leukemia (CML) is also called chronic myeloid leukemia, chronic myelocytic leukemia, and chronic granulocytic leukemia.
This is a cancer of the white blood cells. In CML, blast cells, or immature white blood cells, form and multiply uncontrollably, they crowd out all the other types of necessary blood cells.
Symptoms of Chronic Myeloid Leukemia
The symptoms of CML can also be symptoms of a variety of other conditions, which can make them easy to be ignored or dismissed. They include:
- shortness of breath
- night sweats
- bone pain
- weight loss
- sense of “fullness” or bloating in the stomach
- feeling full after eating, even if only a small amount
Symptoms alone will not be enough to diagnose CML because they’re common in several types of cancers, as well as other more common conditions.
Your doctor will need to conduct a physical exam and laboratory tests to confirm a diagnosis. CML can affect your body in other ways, too, especially if you undergo chemotherapy treatment
Causes of Chronic Myeloid Leukemia
CML is caused by a genetic mutation. Doctors do not know what causes the initial mutation. But they do know the genetic mutation that leads to CML is not passed on by parents.
In humans, there are 23 pairs of chromosomes. In individuals with CML, part of chromosome 9 is switched with a piece of chromosome 22. This makes a short chromosome 22 and a very long chromosome 9.
According to Mayo Clinic, the short chromosome 22 is called the Philadelphia chromosome, and is present in 90 percent of CML patients. Genes from chromosomes 9 and 22 combine to form the BCR-ABL gene that enables specific blood cells to multiply uncontrollably, causing CML.
Treatment of Chronic Myeloid Leukemia
There are multiple treatments for CML. Your treatment may vary depending on your health and the progression of the disease.
Targeted therapies are typically used first in CML treatment. These are drugs that attack a specific part of the cancer cell to kill it.
In the case of CML, these drugs block the protein made by the BCR-ABL gene. They may include imatinib, dasatinib, or nilotinib.
Chemotherapy involves using drugs to kill cancer cells. These drugs are systemic, which means they travel through your entire body via your bloodstream.
They can be given intravenously or orally, depending on the specific drug. Chemotherapy is a common cancer treatment with side effects that may be intense.
Bone marrow transplant
A bone marrow transplant(also called a blood stem cell transplant) might be used when other treatments have failed. This is because the procedure is risky, and a matching donor might be difficult to find.
In this type of transplant, chemotherapy is used to kill the cancerous cells in your bone marrow before healthy donor cells are infused into your blood to replace them.
Side effects of this procedure vary widely but can include minor things, like chills and flushing, or major complications, like anemia, infections, and cataracts.
These treatments can be used alone, or in combination with one another. Read more about how CML treatments work, and talk with your doctor about which treatment options are best for you.
Diagnosis of Chronic Myeloid Leukemia
Because CML generally does not cause symptoms in its early stages, the cancer is often detected during a routine blood test. When there are symptoms, they’re typically hard to identify as being caused by CML rather than another health condition.
If tests suggest that you may have cancer, a bone marrow biopsy is performed. This is to get a sample of bone marrow to send to a lab for analysis. A special needle with a tube will be inserted into either your hipbone or breastbone, and a small piece of bone marrow suctioned out.
Once diagnosed, tests will be done to see how the cancer is behaving in your body. These tests help doctors figure out which treatments will be most effective. They may include additional blood work and genetic tests.
Imaging tests, like an MRI, ultrasound, and CT scan, can also be used to determine where the cancer has spread.
Prognosis of Chronic myeloid Leukemia
The prognosis for people diagnosed with CML is generally good, and it’s getting better. New treatments are better at targeting tyrosine kinase, the protein that causes CML.
Likewise, large-scale studies are finding new, more effective treatment options every year.
Factors that can affect your prognosis include:
- phase of CML
- overall health
- platelet counts
- whether your spleen is enlarged
- amount of bone damage caused by the leukemia
The news of a cancer diagnosis can be difficult, even if you’re told the prognosis is good. Learn about the life expectancy and prognosis after a CML diagnosis.
Stages of Chronic Myeloid Leukemia
CML has different phases or stages of progression. Which stage the disease is in determines the appropriate treatment. The stages are based on the number of blast cells present and include:
The Chronic Phase
This is the earliest stage of CML. You may have some symptoms or none at all. During this phase, your white blood cells can still fight infections in your body.
The Accelerated Phase
In this phase, your red blood cell counts are low, and anemia (not enough iron in your blood) may occur.
Platelet levels are also reduced, which may cause easy bruising or bleeding because platelets help to form blood clots. The amount of blast cells increases. A fairly common complication at this point is a swollen spleen, which may cause stomach pain.
The Blast Crisis (Blastic) Phase
A large number of blast cells are present in this advanced phase. Symptoms in this phase are more severe and can be life-threatening.
Survival Rate for Chronic Myeloid Leukemia
The percentage of people living five years after a CML diagnosis is 67.6 percent, according to the National Cancer Institute. But that number is expected to continue to improve as more people with CML use newer targeted therapies.
Most individuals with CML remain in the chronic phase. If they don’t respond well to treatment or don’t take treatment, they can advance to the accelerated or blastic phase.
Life expectancy is shorter in these later stages. But certain health and lifestyle factors can also influence survival rates.
Life Expectancy for Chronic Myeloid Leukemia
Improvements in CML treatment mean that life expectancy is improving every year.
In 1990, a diagnosis of CML reduced life expectancy of a 55-year-old woman by 24.9 years. In 2010, however, a CML diagnosis only reduced life expectancy by 2.9 years.
The greatest increase in life expectancy has been seen in younger people, though older people also see more years.
In fact, in 2013, the life expectancy of patients diagnosed with CML was the closest it has ever been to the life expectancy of the general population.
Chronic Myeloid Leukemia Diet
CML can impact your overall health, causing fatigue and weakness. It can also compromise your immune system, leaving you open to viruses and bacteria that could make you ill. Diet is one way you can boost energy, support your immune system, and boost your overall well-being.
Eat these foods to get more nutrients, vitamins, minerals, and carotenoids in your daily diet:
- whole grains and legumes
- low-fat, lean meats like fish and poultry
- 5 to 10 servings of fruits and vegetables
- low-fat dairy
CML treatments can affect your appetite. But eating a balanced diet is important when you’re undergoing treatments. A healthy diet can reduce side effects and help keep your immune system strong.