Chronic lymphocytic leukaemia (CLL)
Key facts
- CLL is a type of blood cancer that usually progresses slowly.
- It is more common in males over the age of 60 years.
- Because CLL often progresses slowly, you may only need regular check-ups instead of active treatment.
- If treatment is needed, you and your doctor can discuss options such as chemotherapy or targeted therapy.
- Occasionally, CLL can change into a faster-growing disease that needs urgent treatment.
What is chronic lymphocytic leukaemia (CLL)?
Chronic lymphocytic leukaemia (also called chronic lymphatic leukaemia) is a type of blood cancer.
- 'Chronic' means it develops slowly.
- 'Lymphocytic' means it affects cells called lymphocytes.
Chronic lymphocytic leukaemia (CLL) is the most common form of leukaemia diagnosed in Australia. It usually develops slowly. You may live with CLL for many years without noticing any symptoms or needing treatment.
What are the symptoms of CLL?
Some people with CLL have no symptoms. You might only find out you have it after a blood test done for another reason.
If you do have symptoms, they may include:
- fatigue (feeling very tired)
- shortness of breath
- bruising or bleeding more easily than usual
- fever
- night sweats
- unintentional weight loss
- swollen lymph nodes (glands) in your neck, armpit or groin
It's important to remember these symptoms can be caused by many other conditions. If you're worried about any of them, see your doctor.
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What causes CLL?
CLL affects B-lymphocytes (B-cells), which are part of your immune system. If you have CLL, your body makes too many abnormal B-cells. These abnormal cells crowd out the normal blood cells and can cause symptoms.
Most people who develop CLL are adults over the age of 60 years. The chance of getting it increases as you get older. It is more common in males than in females.
When should I see my doctor?
If you have symptoms and are worried it might be CLL, see your doctor. If you already have a CLL diagnosis and start feeling unwell, see your doctor straight away.
If you notice side effects from your CLL medicine, talk to your doctor about ways to manage them.
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How is CLL diagnosed?
To diagnose CLL, your doctor will:
- ask about your symptoms
- examine you
- arrange blood tests
If your doctor thinks you may have CLL, they may refer you to a haematologist. This is a doctor who specialises in blood disorders.
You might also need other tests, including:
- imaging tests — such as CT scans, x-rays or ultrasound
- a bone marrow biopsy — a needle is used to take a sample of the marrow inside a bone, usually the hip bone
- a lymph node biopsy — a fine needle is used to take a sample from a lymph node for testing
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How is CLL treated?
Many people with CLL do not need treatment straight away — and some people never need treatment. Your doctor may suggest 'active monitoring'. This means having regular check-ups and blood tests to watch your health and pick up any problems early.
If there are signs the disease is getting worse or your symptoms are causing you problems, you might need treatment. This may include:
- chemotherapy
- targeted therapies, such as monoclonal antibodies that help your immune system fight the cancer
- a combination of these treatments
These treatments can cause side effects, such as:
- tiredness
- nausea
- a higher chance of infections
You and your doctor can discuss medicines or treatments to help manage any side effects.
On rare occasions, a stem cell transplant may be an option. This is usually for younger people with aggressive CLL. This is because the risks may be greater than the benefits for most people.
Alongside main treatments, you may choose supportive therapies to help manage symptoms. These may include antibiotics, blood transfusions and extra immunisations.
Living with CLL
If you have been diagnosed and treated for CLL, you might choose to take some time to adjust to any physical and emotional changes. You might also re-evaluate certain aspects of your life, such as your workload, and establish a new routine.
Once you are diagnosed with CLL, you will need to have the condition monitored for the rest of your life.
Maintaining a healthy lifestyle can support your overall health and help you cope better with the condition. Some things you can do to maintain a healthy lifestyle include:
- quitting smoking
- eating a balanced diet
- staying physically active
- managing fatigue
- caring for your mental wellbeing
Staying informed and connected with your healthcare team helps you make decisions and live well with CLL.
What are the complications of CLL?
In some people with CLL, the disease can change into a type of lymphoma called diffuse large B-cell lymphoma. This is a fast-growing type of cancer that needs to be treated quickly.
When you have CLL, you are at a higher risk of some other conditions such as skin cancer and infections. Regular check-ups with your doctor are important.
Can CLL be prevented?
While you can't prevent CLL itself, you can lower your chance of complications once you have been diagnosed. This includes:
- keeping up to date with immunisations
- attending cancer screenings (for skin, breast, prostate, bowel and lung cancer if you are at risk)
- avoiding infections by washing your hands regularly, practising good hygiene and seeking early care for fevers or other signs of infection
- following a healthy lifestyle
Resources and support
- Contact your local Cancer Council for more information.
- Leukaemia Foundation provides blood cancer information and practical support.
- Lymphoma Australia educates and supports people diagnosed with lymphoma.
- Cancer Australia has information on leukaemia, and can help you find support.
- Call Quitline on 13 7848 (13 QUIT) for support to quit smoking.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.
Languages other than English
Cancer Council has information on CLL in many community languages.
Information for Aboriginal and/or Torres Strait Islander peoples
Cancer Council NSW and Cancer Council Victoria have resources for Aboriginal and/or Torres Strait Islander peoples.
Our Mob and Cancer has information about cancer, including cancer types and living with cancer for Aboriginal and/or Torres Strait Islander peoples.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: August 2025