- Chronic myeloid leukaemia (CML) starts when the bone marrow produces an excess of white blood cells that grow and spread abnormally
- These white blood cells are called granulocytes. They are a type of myeloid blood cell that move through a large network of tissues and organs called the lymphatic system and impact areas such as the lymph nodes, spleen and liver
- Chronic leukaemia can develop slowly and may take months or years for symptoms to develop
- CML is a rare type of chronic leukaemia, with 376 Australians estimated to have been diagnosed in 2021
- Adults over the age of 40 account for nearly 70% of all CML cases in Australia
Chronic Myeloid Leukaemia
Chronic myeloid leukaemia is a type of blood cancer which develops when the body has too many abnormal white blood cells, known as granulocytes.
All cases of CML have a chromosomal abnormality called the Philadelphia chromosome. Your cells contain 23 chromosomes and the Philadelphia chromosome develops in chromosome 22 when part of chromosome 9 joins onto it. This new type of chromosome contains the BCR-ABL gene that tells leukaemia cells to grow and spread.
As signs and symptoms for CML can be similar to other common conditions, it’s important to see your GP or healthcare professional if you experience any of the symptoms below. In many cases, these symptoms may not show for months or years after developing CML. Discussing anything concerning with your doctor as soon as possible can help give you peace of mind and offer the best chance of successful treatment if you receive an CML diagnosis.
Although CML has no symptoms in many cases and is often diagnosed during routine blood tests, symptoms may include:
Anaemia, including dizziness, paleness and shortness of breath
Unexplained weight loss and loss of appetite
Enlarged abdomen and feeling full after eating a small amount
Increased bleeding and bruising
Unlike other cancers, CML is classified into phases rather than stages. These phases are based on the number of immature white blood cells in your bone marrow and blood.
This phase can last many years and is when most people are diagnosed. During this phase the blast cell (immature cells) numbers in the blood and bone marrow are low (< 5%), which means the phase is relatively stable. There are few (if any) symptoms in this stage.
During the accelerated phase, the number of blast cells start to increase in the bone marrow and blood.
The blast phase is a period of rapid progression where blast cell numbers in the blood and bone marrow increase quickly. Symptoms often worsen and the patient is considered to have a form of acute leukaemia.
CML is not hereditary. Although genetic abnormalities can cause CML, these are not passed down from parents and instead occur during your lifetime.
The causes of CML are not fully known. However, there are some factors which contribute to the risk of CML developing, including:
- Age – Nearly 70% of all cases of CML are diagnosed in adults over the age of 40
- Gender –Men are more likely to develop CML than women
- Genetic abnormalities – Nearly all people with CML have a genetic abnormality known as the Philadelphia chromosome. It contains the BCR-ABL gene that tells leukaemia cells to grow and spread. The Philadelphia chromosome is not inherited and cannot be passed down
- Exposure to radiation and certain chemicals – Exposure to high doses of radiation and benzene, as well as some chemotherapy treatments increase your risk of developing CML
Leukaemia is less common than other cancer types, affecting 1 in 61 Australians by the age of 85. CML is a rare type of chronic leukaemia. In 2021 there were 376 cases of CML, with more males than females diagnosed.
There are many different tests that are used to diagnose CML, alongside a physical examination. This includes blood tests and a bone marrow biopsy. The Philadelphia chromosome can be detected in blood or bone marrow, and a DNA-based test called BCR-ABL1 will be performed at diagnosis and monitored throughout your treatment. You may also receive an ultrasound to identify if your spleen has been affected.
CML and CLL are two forms of chronic leukaemia which develop from different types of white blood cells. CML develops from myeloid cells called granulocytes, while CLL develops from lymphocytes such as B-cells and T-cells.
There are no known ways to prevent CML. However, there are a number of lifestyle-related factors you can consider to reduce your risk of developing cancer overall, like:
- Avoiding high doses of radiation and certain chemicals
- Getting regular exercise – Cancer Australia recommends at least 30 minutes of moderate-intensity exercise each day
- Eating a healthy, balanced diet – Eat a fibre-rich diet from grain and legume sources, as well as enjoy a variety of fruit (2 serves) and vegetables (5 serves) per day, limit your intake of salt and saturated fats, and avoid all processed meat
Icon offers clinical trials across a wide range of cancer types and treatments. If you would like more information on participating in a clinical trial, please speak with your doctor who will be able to find a trial that might be right for you and your cancer.
- Cancer Council. (2018). Understanding Chronic Leukaemia: A guide for people with cancer,
- their families and friends. Retrieved 12 January 2022 from https://www.cancer.org.au/assets/pdf/understanding-chronic-leukemia-booklet
- Leukaemia Foundation. (2020). Chronic myeloid leukaemia (CML). Retrieved 12 January 2022 from https://www.leukaemia.org.au/blood-cancer-information/types-of-blood-cancer/leukaemia/chronic-myeloid-leukaemia/
- Cancer Council. (2020). Chronic myeloid leukaemia (CML). Retrieved 12 January 2022 from https://www.cancercouncil.com.au/chronic-myeloid-leukaemia/#Who-gets-CML
- American Cancer Society. (2018). Chronic Myeloid Leukemia (CML). Retrieved 12 January 2022 from https://www.cancer.org/cancer/chronic-myeloid-leukemia.html
- Macmillan Cancer Support. (2020). Chronic myeloid leukaemia (CML).. Retrieved 12 January 2022 from https://www.macmillan.org.uk/cancer-information-and-support/leukaemia/chronic-myeloid-leukaemia-cml
- Cancer Australia. (2022). Leukaemia in Australia statistics. Retrieved 12 January 2022 from https://www.canceraustralia.gov.au/cancer-types/leukaemia/statistics
- Australian Institute of Health and Welfare. (2021). Cancer data in Australia: Summary. Retrieved 12 January 2022 from https://www.aihw.gov.au/reports/cancer/cancer-data-in-australia/contents/cancer-summary-data-visualisation
Helpful linksBecoming a patient
Chemotherapy explained - Colin's experience with leukaemia
Icon North Lakes patient Colin shares his story about receiving a leukaemia diagnosis and what to expect during chemotherapy treatment
What you need to know about cancer research and clinical trials
View a Facebook Live with Icon specialists from across Australia and Singapore
Clinical Opinion Article
Five tips for life beyond cancer treatment
Icon Medical Director and Clinical Haematologist Dr Ian Irving shares his advice on how to stay well and find your new normal once treatment ends
Become a patient
Find out how to become a patient at Icon Cancer Centre, or request more information from your nearest centre.
Icon brings together some of Australia’s most experienced medical oncologists, radiation oncologists and haematologists.
Care at Icon
At Icon, care is more than just a word. Our cancer care team are here to support you with compassion, knowledge and hope.
Our patients share their perspective and advice.