Chronic lymphocytic leukaemia (CLL) is a serious condition, but it develops slowly. If you’re diagnosed with CLL, you might not need treatment right away. CLL can’t usually be permanently cured, but treatment can often keep the cancer cells under control for a while, often for years.

The name explains a couple of things about this condition. ‘Chronic’ means CLL can take a long time to progress, and ‘lymphoid’ tells you that it affects a particular group of white blood cells.

CLL happens because your body’s process for making white blood cells, called haematopoiesis, isn’t working correctly. There are too many lymphocytes (a type of white blood cell) and many of them are not fully mature. Over time, the lymphocytes can start crowding out your red blood cells and platelets.

You can learn more about blood cells and haematopoiesis, in our general information about leukaemia.

What are the symptoms of CLL?

Many people with CLL don’t feel unwell at first. It’s often picked up by chance, when you have a blood test for another reason.

The main symptom is usually swollen glands in your armpits, neck or groin.

Other symptoms of CLL can include:

  • Swelling in your abdomen
  • Feeling very tired
  • Pale skin
  • Feeling breathless
  • Unusual bleeding
  • Bruises
  • Getting lots of infections
  • Fever
  • Losing weight
  • Night sweats.

What causes CLL?

We don’t know what causes CLL. Most commonly, it appears between the ages of 60 and 80. It occurs more often in men than in women.

CLL is more likely to happen when you have a close relative with the condition, but we can’t identify a specific gene that explains it. If someone in your family has CLL, the risk that you will also have it is still small.

How is CLL diagnosed?

A blood test that shows high levels of lymphocytes is often the first sign of CLL. If CLL is suspected, you’ll be offered further blood tests to confirm the diagnosis.

You may also be offered a bone marrow biopsy.

The cancer cells in your blood and bone marrrow can be tested for abnormal genes, to find out what type of CLL you have. This information is important because it gives an idea of the outlook, and which treatment might work best for you.

You may also be offered a chest X-ray, ultrasound scan or CT scan.

You’ll have regular check-ups and blood tests to monitor your condition if you don’t need treatment right away, or to check how well it is working if you do start treatment.

You can read more in our information about tests for leukaemia.

What are the stages of CLL?

Your test results will show how far the CLL has advanced. This information, called staging, gives an idea of the outlook and helps in choosing the best treatment.

The Binet staging system is the one that is used most in the UK. It has two parts, based on:

  • How many lymph glands are enlarged, and whether your spleen or liver is enlarged.
  • How many white blood cells there are, and how much they have crowded out your other blood cells.

The stages are ranked by the letter A (least advanced cancer), B or C (most advanced).

What is the treatment for CLL?

The choice of treatment depends on how advanced the cancer is, the type of CLL you have, and your overall health.

If the CLL is at an early stage, your doctor may recommend simply keeping an eye on it with reguar blood tests and check-ups. That’s because CLL progresses slowly, and in this situation the drawbacks of treatment might outweigh the benefits.

When treatment is needed, it may combine chemotherapy with a drug that works on your immune system.

Some of the chemotherapy drugs for CLL are:

  • Fludarabine (also called Fludara)
  • Cyclophosphamide (Cytoxan)
  • Chlorambucil
  • Bendamustine (Levact)

These are usually given alongside a drug that works on your immune system, such as:

  • Rituximab (MabThera, Rixathon, Truxima)
  • Obinutuzumab (Gazyvaro)
  • Ofatumumab (Arzerra)

Other new drugs for CLL include:

  • Ibrutinib (Imbruvica)
  • Idelalisib (Zydelig)

A few people are offered a stem cell transplant for CLL (also known as a bone marrow transplant). It’s tough on your body, so it’s not the right choice for everyone.

Guidelines on CLL say that everyone with this condition should be offered the chance to join a clinical trial if one that suits your circumstances is available.

Supportive care can also help you avoid infections and stay as well as possible.

What is the outlook (survival) for CLL?

The outlook depends on your age, how advanced the cancer is, and your general health. Overall, about 7 in 10 people with CLL live for 5 years or more after their diagnosis.

For information about what happens after treatment for CLL, and places to find extra support whatever your situation, read our section on living with leukaemia.