Chronic lymphocytic leukaemia (CLL): symptoms, diagnosis and treatment

The NHS says many people who have CLL do not have any symptoms, and that symptoms are not always obvious at first and can be similar to other conditions. Cancer Research UK says many people are diagnosed because they have a routine blood test for something else. Symptoms are usually mild at first, may feel like flu, and get worse slowly.

The NHS lists the main symptoms below. Cancer Research UK adds that anaemia and bleeding or bruising are generally later symptoms of CLL, and that bone pain and night sweats occur in some people whose CLL has changed (transformed) into a higher-grade disease.

• Swollen glands, usually in your neck or under your arms. Cancer Research UK says an enlarged spleen can also cause discomfort in the tummy, on the left under the ribs.

• Losing weight. Cancer Research UK says CLL itself uses up energy that your body would otherwise use or store.

• Getting ill a lot, or infections that will not get better, because the abnormal white blood cells cannot fight infection as well as healthy ones.

• Feeling tired even though you have had a good night's sleep, and looking unusually pale and feeling breathless, which may be anaemia.

• Bleeding or bruising for no reason, or a rash that looks like small bruises and does not fade when you roll a glass over it.

• A high temperature even though you are not unwell, aches and pains that will not go away, and sweating at night.

Leukaemia is a blood cancer. Cancer Research UK explains that in most types, abnormal white blood cells are made in the bone marrow, get into the bloodstream and do not work normally. They can build up in the lymph nodes and spleen and cause swelling, and can crowd out the bone marrow so that not enough healthy blood cells are made.

Leukaemias are divided into acute, which develop quickly and get worse rapidly without treatment, and chronic, which develop slowly and tend to get worse slowly over a long time. In chronic leukaemia the white blood cells are almost fully developed but not completely normal, so they still work, but not as well as they should.

In CLL it is the B lymphocytes that are cancerous. Cancer Research UK also describes small lymphocytic lymphoma (SLL), which is very similar: the abnormal B cells are mainly in the lymph nodes rather than the blood and bone marrow, so doctors call it a lymphoma, and treatment for CLL and SLL is the same.

The NHS says it is not clear what causes CLL. It is rare, but more common as you get older (very rare in people under 40), if you are male, and if someone in your family has had it. The NHS says having a close family member who has had it may mean you have a slightly higher risk.

Cancer Research UK says it does not know what causes most cases, although some factors may increase risk. It also says chronic leukaemia in children is very rare, as childhood leukaemia is nearly always acute.

Cancer Research UK says you usually start by seeing your GP if you have symptoms or an abnormal blood test result, and your GP decides whether to refer you for further tests or to a hospital specialist. It says your GP should refer you for an urgent blood test if your symptoms could be due to CLL. The NHS says the GP may examine any swollen or painful areas and arrange a blood test, and that an urgent referral, usually within 2 weeks, may be made if you have certain symptoms. This does not definitely mean you have cancer.

The NHS says the main tests are blood tests to check your blood cells and look for signs of leukaemia. Cancer Research UK says doctors can usually diagnose CLL by checks on the cells in a blood sample (immunophenotyping), then do other tests to find out more, including tests on blood and bone marrow for changes in certain genes. There is no screening programme for CLL in the UK.

After diagnosis the NHS says you will usually need more tests, such as scans (CT or ultrasound), a chest X-ray, and blood and bone marrow tests. These help the specialists work out how much the cancer has developed (the stage), which guides whether you need treatment now. Cancer Research UK says there are 3 stages, A, B and C.

The NHS says it is not possible to cure CLL, but treatment can control it, and you can live with CLL for years and may need to repeat treatment several times. When treatment starts depends on your symptoms, the stage of the cancer and your general health.

The main treatments are targeted medicines, which aim to stop the cancer growing or help your immune system fight it. The NHS says you will usually have them on their own, or sometimes with chemotherapy. Cancer Research UK says they can be given as tablets or as a drip into a vein.

Cancer Research UK says you might not need treatment straight away or ever, and that doctors monitor you with regular check-ups and tests, called watch and wait, active monitoring or active surveillance. The NHS says you will usually be seen by a doctor or nurse regularly, and how often depends on the stage of your cancer, whether you are having treatment and how you are feeling.

Being told you have a cancer and that no treatment is needed yet can be hard. The NHS says to talk to your specialists if you have symptoms or side effects that worry you, and that you do not need to wait for your next check-up. It also points to support from family, friends or a support organisation if you feel anxious between appointments, and mentions CLL Support and Blood Cancer UK.

The NHS says that when symptoms come back this is called a relapse. It may happen slowly, you may not need treatment straight away, and you may have several relapses while you live with CLL. More tests then help doctors decide which treatments will work best. When symptoms are under control this is called remission, which can last for years.

Cancer Research UK says CLL can rarely change over time into prolymphocytic leukaemia, and that advanced CLL can sometimes develop into a lymphoma called Richter's syndrome, which affects between 2 and 10 out of every 100 people with CLL.

The NHS says to see a GP if you have symptoms of CLL, noting that these symptoms are very common and can be caused by many other conditions, and having them does not definitely mean you have CLL. Getting them checked matters because if they are caused by cancer, finding it early can mean it is more treatable.

The NHS includes a rash of small bruise-like spots that does not fade when a glass is rolled over it, similar to meningitis, among the symptoms to get checked. If you are acutely unwell, for example severely breathless, bleeding heavily or with a high temperature and feeling very ill, call NHS 111 or 999 as you would for any emergency. If you are already being treated for CLL, ask your team who to call out of hours, as infections can become serious quickly.

On the NHS, a GP can arrange blood tests and refer you to a haematology team. The NHS says a group of specialists will look after you, including a clinical nurse specialist who is your main point of contact. Macmillan Cancer Support runs a free helpline, open every day from 8am to 8pm, which the NHS lists as a source of support.

Some people choose a private haematology consultation for tests or a second opinion. If you do, ask for the results to be shared with your NHS team so that monitoring stays in one place.