Chronic myeloid leukaemia information

Chronic myeloid leukaemia (CML) is a cancer of the blood. The leukaemia is termed ‘chronic’ because it develops very slowly.

In this section

When a patient develops CML, too many white blood cells are produced within their bone marrow. These cells, which are known as blast cells, are released into the blood before they have developed properly and so they do not behave in the way healthy white blood cells do. The over-production of blast cells in the bone marrow also means that other types of blood cells normally found in the blood are not produced.

The information on the following pages relates to adults with CML.


The signs and symptoms of CML vary from patient to patient but may include the following:

  • a feeling of exhaustion
  • pale skin
  • increased bruising of the skin
  • a feeling of fullness in the abdomen or a tender lump on the left-hand side of the abdomen due to an enlarged spleen

Many of these symptoms are caused by the increased numbers of abnormal white blood cells and a decrease in the amount of normal blood cells in the blood stream and the bone marrow.

Feeling tired and looking pale is a sign of a lack of red blood cells (anaemia). Bruising of the skin is a sign of a lack of blood cells called platelets.


A series of tests or investigations will be done to confirm or rule out a diagnosis of chronic myeloid leukaemia (CML) and to check on your general health. These tests may include:

Bone marrow sample

In order to confirm what type of leukaemia you have and to plan your treatment, it is necessary to examine a small sample of bone marrow. This is normally taken from your hip bone and is examined to determine whether abnormal white blood cells are present and if so what type they are.

The process is conducted under local anaesthetic and is not painful, although some patients find it uncomfortable. The procedure will be explained to you before it is carried out and you will be able to ask any questions or raised any concerns you might have.

Blood tests

Blood tests will be taken throughout your treatment to monitor how you are responding and how effective your treatment is.


There are several ways of treating chronic myeloid leukaemia (CML) and your treatment will be planned individually for you. Don't be concerned if you talk to other people who are receiving similar, but different, treatments. The aim of treatment is to control the leukaemia and its symptoms so that your quality of life is good.


Chemotherapy means treatment with anti-cancer drugs which destroy cells by damaging them so that they can't divide and grow. Normal cells recover quickly, the leukaemia cells do not. As the drugs circulate in the blood, they reach leukaemia cells all over the body.

Your treatment plan will be fully explained to you by your consultant or clinical nurse specialist. Please ask any questions you have about the drugs and why they have been chosen. Chemotherapy drugs may be given by mouth or intravenously.

You will need to be admitted to hospital for a period of three or four weeks.

Chemotherapy is normally given at intervals over several weeks or months. During this time you will have regular blood tests and bone marrow transplants to monitor your progress.

Other drugs

There are specialist drugs used in the treatment of CML. They are used in conjunction with chemotherapy. If these will form part of your treatment, your consultant and clinical nurses specialist will explain why they are being given to you and what the benefits and side effects may be.

Stem cell transplant

You may be offered high-dose chemotherapy which is intensive treatment. In addition to destroying leukaemia cells, this treatment will also destroy healthy bone marrow cells. A peripheral stem cell transplant will give you a source of healthy bone marrow that will produce normal white blood cells.

If a transplant forms part of your treatment, your consultant and clinical nurse specialist will explain the procedure in more detail and discuss the benefits and side effects with you.

After treatment

Having chronic myeloid leukaemia (CML) and being treated for it will have an effect on your life.


Treatment for CML, as with other leukaemia, is very effective and can control the condition and the symptoms you experience for many years.

After your treatment is finished you will continue to be monitored with regular checkups and blood tests. If you notice new symptoms or have any concerns about your health between appointments, contact your doctor.

Sex and fertility

Some chemotherapy drugs can damage the ovary or testes, leading to an increased risk of infertility and, in women, early menopause.

Chemotherapy may affect sexual organs or functions in various ways. You may experience changes in your desires or desired level of sexual activity or you may notice no difference. Loss of libido (sex drive) is not uncommon in both women and men. However, chemotherapy in itself doesn’t usually affect sexual performance or cause impotence.


During your treatment you may start to feel tired and listless. This may be general fatigue or it may be that you become tired more easily after normal activities. This is quite normal and usually occurs with leukaemia and its treatments.

Do talk about how you are feeling with your consultant or clinical nurse specialist. They will be able to suggest ways of conserving your energy or may be able to treat the causes of your tiredness, such as not being able to sleep or anaemia.

If you are at home, try to plan your day so that light activities are spaced between more energetic activities. Do get enough rest and only do what you feel you can cope with.

People will often be willing to lend their support. If you get tired easily, limit your activities and conserve your energy for the things that mean the most to you. Ask your family and friends to help with household chores.