Chronic Lymphocytic Leukaemia (CLL) is the most common type of leukaemia but it's rare in people under the age of 40. It appears gradually and develops slowly over months to years.
- It is a cancer of the lymphocytes (a type of white blood cell). It affects a particular lymphocyte, the B cell, which originates in the bone marrow, develops in the lymph nodes, and normally fights infection.
- When CLL is present, the DNA of a B cell is damaged, and it can no longer fight infection. These damaged cells grow out of control and crowds out the healthy blood cells.
What causes chronic lymphocytic leukaemia?
The cause of CLL isn’t known, but research is going on all the time to try to find out. Like other leukaemias, it’s not infectious and can’t be passed on to other people.
In some cases – about one in 10 – other people in the family will also have CLL. This is known as familial CLL. If you know that other family members have CLL, it is important to let your specialist know.
What are the symptoms?
Many people have no symptoms in the early stages of CLL and it may be discovered only when a blood test is taken for a different reason.
As it advances, however, CLL can result in the following symptoms:
- Frequent infections, as without enough mature, healthy white blood cells it’s a lot harder to fight off bacteria and viruses.
- Tiredness and sometimes breathlessness, caused by a lack of red blood cells (also known as anaemia). There are often not enough red blood cells because the abnormal lymphocytes are taking up too much space in the bone marrow.
- Unexplained bruising or bleeding, such as nosebleeds, caused by a lack of platelets in the blood.
- Abnormal lymphocytes may collect in lymph glands and cause swellings in the neck, armpits or groin.
- The spleen may become enlarged and cause a tender lump in the upper left-hand side of the stomach.
- Some people will have sweating or a high temperature at night.
- Some people lose weight.
How is it diagnosed?
CLL is relatively easy to diagnose.The GP will perform a complete blood count (CBC) test and if it shows an unusually high level of one type of white blood cell, a referral will be made to a haematologist (blood specialist), for advice and treatment.
The haematologist will ask about the patients full medical history and do a physical examination to check for any enlargement of the lymph nodes, spleen or liver.
They will also need to have more blood tests. If the tests show leukaemia cells, the patient may need to have a bone marrow biopsy for a clear diagnosis, and to help with planning the best treatment for them.
The tests on the blood and bone marrow sample may include:
- Cytogenetic tests: a chromosome analysis to look for any particular changes in the chromosomes. People with CLL often show changes in the chromosomes and finding exactly what those changes are helps the doctor work out how well the leukaemia will respond to treatment.
- Immunophenotyping: where samples are examined to see exactly which white blood cells are abnormal. Knowing this helps the doctors to plan the best treatment for the patient.
- Tests to look at the levels of antibodies in the blood and whether particular proteins are present that may damage the red blood cells.
- It may be necessary to remove an enlarged lymph gland to look at the cells under a microscope. This is called a lymph node biopsy.
- A chest x-ray is usually taken to check that the lungs are healthy. They may also have a CT scan to see how many lymph glands are affected by the CLL and whether the patients spleen is enlarged.
How is it treated?
At the moment, CLL is not regarded as curable. However, treatments are very successful in getting most people into remission, and this can last for a number of years. The aim of treatments is to allow people with CLL to have a normal life with no symptoms, for as long as possible.
The type of treatment depends on the stage of CLL, as follows:
Many people with stage A CLL do not need to have treatment unless their leukaemia progresses. This is because stage A CLL doesn’t cause any symptoms and develops very slowly. Early treatment at this stage does not help people to live longer and can cause unpleasant side effects.
Note: even if you’re not having treatment, it’s still important to have regular check-ups and blood counts, as this is the best way of monitoring leukaemia. Treatment is only started if the CLL starts to progress or if symptoms become troublesome.
Stage B and C:
Treatment at these stages may include:
- Steroids, to help the chemo work more effectively
- High-dose chemotherapy and stem cell transplant may be suggested for younger patients as it has been shown to result in a long period of remission in some people. This is a more aggressive type of treatment and often not suitable for older patients.
- Radiotherapy is sometimes used to treat enlarged lymph nodes, or an enlarged spleen.
- Surgery is occasionally used to remove an enlarged spleen. This is known as a splenectomy.
- People who have infections may need to have antibiotics to treat them.
- People who have very low levels of red blood cells (anaemia) may need to have a blood transfusion.
- Occasionally, people who are very prone to infection may need to have antibodies (immunoglobulins) given by drip (infusion).