Chronic Myeloid Leukemia (CML)

Chronic Myeloid Leukemia (CML)

Chronic Myeloid Leukemia (CML) is a blood cancer that starts in the myeloid cells or stem cells in the bone marrow.  In CML, the bone marrow produces too many white blood cells, which do not function properly that can accumulate in the blood and other organs. You can develop CML at any stage but it typically affects older adults. It is also called Chronic myelogenous leukemia or chronic granulocytic leukemia. 

CML is caused by a genetic mutation in the stem cells that produce white blood cells. This mutation causes the cells to produce an abnormal protein called BCR-ABL, which triggers the uncontrolled growth of white blood cells. The advances in treatments by our healthcare professionals have turned this life-threatening illness into a chronic illness with a normal life span.

Symptoms

The signs and symptoms of Chronic Myeloid Leukemia (CML) may not be noticeable in the early stages. However, some people may experience mild to severe symptoms from the condition that includes –

• Shortness of breath
• Fatigue or weakness
• Abdominal swelling
• Night sweats
• Fever

Chronic Myeloid Leukemia (CML)

• Unexplained weight loss
• Abdominal swelling in the upper left part of your body 
• Eating disorders such as feeling full even when you haven’t eaten too much

Causes and Risk Factors

The cause of Chronic Myeloid Leukemia (CML) is often linked with acquired genetic mutations or changes in myeloid cells growing in the bone marrow. The abnormal changes in genes happen during your lifetime. 

The risk of developing Chronic Myeloid Leukemia (CML) is only exposure to high amounts of radiation and this applies to very few people. People experiencing this chronic illness may also face other ailments such as –

• Anemia – lack of red blood cells causes this condition to occur
• Enlarged Spleen – It happens due to swelling or discomfort in the upper part of your abdomen.

Diagnosis and Tests

Healthcare providers will diagnose Chronic Myeloid Leukemia (CML) by identifying genetic changes or mutations with the help of genetic tests. Some of the common tests for CML performed are –

1. Complete Blood Count (CBC) – Providers check for white blood cells or red blood cell levels in the procedure.
2. Bone marrow aspiration – A tissue or fluid sample for genetic tests is taken to perform medical tests to determine the growth of abnormal cells.
3. Computed Tomography (CT) scan – Providers will determine if CML is affecting other body parts.
4. Ultrasound – It uses sound waves to determine if your spleen is larger than normal. An enlarged spleen is a sign of CML.

Stages 

Chronic Myeloid Leukemia (CML) is not characterized by stages. They are classified as being in one of four phases.

1. Chronic CML – Refers to the percentage of blasts (immature white blood cells) in the bone marrow and blood. It contributes to 10% of blood and bone marrow. Around 80 to 90% of people have chronic CML but very few people show symptoms.
2. Accelerated CML – It makes up 10 to 19% of cells in blood or bone marrow. Providers may also check for basophil levels in your blood. Basophils are white blood cells that control the blood flow with the help of enzymes. A high basophil level signifies that you may have chronic CML.
3. Blast CML – It can be a life-threatening phase as it contributes to around 10 to 20% of cells in blood or bone marrow. You may experience noticeable signs and symptoms such as fatigue, fever, weight loss, and shortness of breath.
4. Resistant CML – It usually comes back after treatment or does not respond to treatment.

Treatments

There are several treatments for Chronic Myeloid Leukemia (CML), including targeted therapy, chemotherapy, and stem cell transplantation. The choice of treatment depends on several factors, such as the phase of the disease, the age and overall health of the patient, and the presence of other medical conditions. Here are some of the treatments for CML –

1. Targeted therapy – The most common and effective treatment for CML is targeted therapy with drugs called tyrosine kinase inhibitors (TKIs). These drugs block the activity of the abnormal protein BCR-ABL, which is responsible for the uncontrolled growth of white blood cells in CML. Examples of TKIs include imatinib, dasatinib, nilotinib, and bosutinib. TKIs are usually taken orally and are generally well-tolerated with manageable side effects.
2. Chemotherapy – Chemotherapy involves the use of drugs to kill cancer cells. It may be used to treat CML in the blast phase or if TKIs are not effective. Chemotherapy drugs for CML include hydroxyurea and busulfan.
3. Stem cell transplantation – Stem cell transplantation, also known as bone marrow transplantation, involves replacing the patient’s diseased bone marrow with healthy stem cells from a donor. It may be an option for people with advanced CML who have not responded to other treatments or who have relapsed after treatment.

The treatment for CML is usually life-long, even if the disease goes into remission. Treatment aims to control the growth of cancer cells and prevent complications while minimizing side effects and preserving the quality of life. It is important to discuss treatment options with a healthcare provider to determine the best course of action for each individual case.

Clinical trials

Clinical trials are research studies that test new treatments or combinations of treatments for CML. These trials may offer access to new treatments that are not yet available to the general public.