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Information about Chronic lymphocytic leukaemia

What is it?

This is a summary of information about this condition. For more detailed information we recommend using the NHS Choices website, A link to this can be found in the External Resources tab above.

Chronic lymphocytic leukaemia (also known as lymphoid leukemia - CLL) is a type of blood cancer that affects the white blood cells and tends to progress slowly over many years.

It mostly affects people over the age of 60 and is rare in people under 40. Children are almost never affected.

In CLL, the spongy material found inside some bones (bone marrow) produces too many white blood cells called lymphocytes that aren't fully developed and don't work properly.

Over time this can cause a range of problems, such as an increased risk of picking up infections, persistent tiredness, swollen glands in the neck, armpits or groin, and unusual bleeding or bruising.

CLL is different from other types of leukaemia, including chronic myeloid leukaemia, acute lymphoblastic leukaemia and acute myeloid leukaemia.

What causes it?

it's not clear what causes CLL. there's no proven link with radiation or chemical exposure, diet or infections. It cannot be caught it from anyone else or be passed on.

However, having certain genes can increase the chances of developing CLL. Individuals may be at a slightly higher risk of it if they have a close family member with it, although this risk is still small.

What are the symptoms and signs?

CLL doesn't usually cause any symptoms early on and may only be picked up during a blood test carried out for another reason.

When symptoms develop, they may include:
  • getting infections often
  • anaemia – persistent tiredness, shortness of breath and pale skin
  • bleeding and bruising more easily than normal
  • a high temperature (fever)
  • night sweats
  • swollen neck, armpit or groin glands
  • swelling and discomfort in the abdomen
  • unintentional weight loss

What tests are used to diagnose it?

Most cases of chronic lymphocytic leukaemia (CLL) are detected during blood tests carried out for another reason.

Some of the tests used are:
  • Blood tests - The main test used to help diagnose CLL is a type of blood test called a full blood count. An abnormally high number of unusual white blood cells (lymphocytes) can be a sign of CLL. A detailed examination of these cells can usually confirm the diagnosis.
  • X-rays and scans - usually chest X-ray , an abdominal ultrasound scan or a computerised tomography (CT) scan
These tests can check for problems caused by CLL, such as swollen glands or a swollen spleen, and help rule out other possible causes of the symptoms.

Other tests include:
  • Bone marrow biopsy - removing a sample of bone marrow (bone marrow biopsy) so it can be examined under a microscope to check it for cancerous cells.
  • Lymph node biopsy - removing and examining a swollen lymph gland can help confirm a diagnosis of CLL. This is known as a lymph node biopsy.
  • Genetic tests - tests may also be carried out on blood and bone marrow samples to check for any unusual genes in the cancerous cells.

What treatments are available?

As CLL progresses slowly and often has no symptoms at first, treatment may not needed immediately.

If CLL starts to cause symptoms, or isn't diagnosed until later on, the main treatments are:
  • chemotherapy – where medication taken as a tablet or given directly into a vein is used to destroy the cancerous cells
  • a stem cell or bone marrow transplant – where donated cells called stem cells are transplanted into the body so the patient starts to produce healthy white blood cells
Treatment can't usually cure CLL completely, but can slow its progression and lead to periods where there are no symptoms. Treatment may be repeated if the condition comes back.

More information

Chronic lymphocytic leukaemia (CLL) can sometimes cause a number of further complications.

Some of the main problems people with the condition may experience are outlined below.

People with CLL usually have a weakened immune system and are more vulnerable to infections because they have a lack of healthy, infection-fighting white blood cells.

Treatment with chemotherapy can also further weaken the immune system.

If you have CLL, it's a good idea to:
  • report any possible symptoms of an infection to your GP or care team immediately – things to look out for include a high temperature (fever), aching muscles, diarrhoea or headaches 
  • ensure your vaccinations are up-to-date – speak to your GP or care team for advice about any additional vaccines you might need, as some aren't safe if you have a weak immune system 
  • avoid close contact with anyone who has an infection – even if it's an infection to which you were previously immune, such as chickenpox 

You may also be prescribed regular doses of medications such as antibiotics to help reduce the risk of infection.

Richter's syndrome
In up to 1 in every 20 people with CLL, the condition will change to become very similar to an aggressive form of non-Hodgkin lymphoma. This is called Richter's transformation or Richter's syndrome.

Symptoms of Richter's syndrome include:
  • sudden swelling of your lymph glands 
  • a high temperature (fever) 
  • night sweats 
  • unintentional weight loss 
  • tummy (abdominal) pain 

Richter syndrome is usually treated with a combination of chemotherapy and other powerful medicines.

The Cancer Research UK website has more information on Richter's syndrome.

Autoimmune haemolytic anaemia
Around 1 in every 10 people with CLL will develop a condition called autoimmune haemolytic anaemia.

This is where the immune system starts to attack and destroy red blood cells. It can cause severe anaemia, making you feel breathless and easily tired.

It is usually treated with steroid medication.

Psychological effects
Being diagnosed with CLL can be very distressing and difficult to take in at first, particularly as it can't necessarily be cured and you may be advised to wait for it to get worse before starting treatment.

Having to wait years to see how the condition develops can also be very stressful and make you feel anxious or depressed. Speak to your GP or care team if You're finding it difficult to cope.

You may also find it useful to talk to other people who are living with leukaemia. Your GP or care team will be able to provide you with the details of support groups in your area.


NHS Choices website accessed on 23/10/17
Link to the NHS Choices website available in External Resources
Please check NHS Choices website for links to patient organisations if relevant
Contains public sector information licensed under the Open Government Licence v3.0.

The medicines listed below have been approved for use in the UK. Medicines are listed by brand name and the active ingredient shown in brackets. An inverted black triangle (▼) against the name denotes that the medicine is being tracked for adverse events.

If the medicine you are interested in is not shown you can request it to be included by emailing the name of the medicine to

Medicines for this condition

Arzerra (ofatumumab)

Gazyvaro ▼ (obinutuzumab)

Hizentra (human normal immunoglobulin)

HyQvia ▼ (human normal immunoglobulin)

Imbruvica ▼ (ibrutinib)

Leustat (cladribine)

Venclyxto ▼ (venetoclax)

Zydelig ▼ (idelalisib)

Flebogamma DIF (human normal immunoglobulin)

MabThera (rituximab)

Kiovig (human normal immunoglobulin)

Privigen (human normal immunoglobulin)

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