Overview

Chronic myeloid leukaemia (CML) is a type of cancer that affects the white blood cells and tends to progress slowly over many years.

It can occur at any age, but is most common in older adults around 60-65 years of age.

In CML, the spongy material inside some bones (bone marrow) produces too many myeloid cells – immature white blood cells that aren't fully developed and don't work properly.

Title
Chronic Myeloid Leukaemia(CML)

Types

CML is different to other types of leukaemia, including chronic lymphocytic leukaemia, acute myeloid leukaemia and acute lymphoblastic leukaemia.

Symptoms

CML doesn't usually have any symptoms in its early stages and may only be picked up during tests carried out for another reason.

As the condition develops, symptoms can include:

  • tiredness
  • weight loss
  • night sweats
  • tenderness and swelling in the left side of your tummy
  • feeling full after small meals
  • pale skin and shortness of breath
  • a high temperature (fever)
  • bruising and bleeding easily
  • frequent infections
  • bone pain
Causes

CML is caused by a genetic change (mutation) in the stem cells produced by the bone marrow.

The mutation causes the stem cells to produce too many underdeveloped white blood cells. It also leads to a reduction in the number of other blood cells, such as red blood cells.

The change involves bundles of DNA called chromosomes. Within each stem cell, a section of DNA from one chromosome swaps with a section from another.

This change is known as the "Philadelphia chromosome’’It's not known what causes this to happen, but it's not something you're born with and you can't pass it on to your children.

Diagnosis

Some cases of chronic myeloid leukaemia (CML) are detected during blood tests carried out for another reason.

But you should visit your GP if you have worrying symptoms of CML, such as persistent tiredness, unusual bleeding or bruising, unexplained weight loss or night sweats.

Seeing your GP

Your GP will ask about your symptoms and may carry out a simple examination to check for other problems, such as swelling in one side of your tummy.

They may also send a sample of your blood to a laboratory so it can be checked for possible causes of your symptoms.

A very high level of white blood cells in your blood could be a sign of leukaemia. If this is detected, you'll be referred to a haematologist (specialist in blood conditions) for further tests.

Confirming the diagnosis

To confirm a diagnosis of leukaemia, a sample of your bone marrow will need to be removed during a procedure called a bone marrow biopsy.

During a biopsy:

  • an area of skin at the back of your hip is numbed with local anaesthetic
  • a needle is used to remove a small sample of bone marrow
  • you may experience some discomfort while it's carried out, but it shouldn't be painful

The procedure usually takes around 15 minutes and you won't normally need to stay in hospital overnight. You may have some bruising and discomfort for a few days afterwards.

Your bone marrow will be checked for cancerous cells and the cells will be analysed to identify which type of leukaemia you have and how advanced it is.

This can help your doctors determine the best treatment for you

Treatment

With modern treatments, it's often possible to control chronic myeloid leukaemia (CML) for many years. In a small number of cases, it may be possible to cure it completely.

The main treatments are described below.

Imatinib

A medicine called imatinib is now the main treatment for CML. It's usually given soon after a diagnosis is made to slow the progression of the cancer and stop it reaching an advanced phase.

Imatinib works by reducing the production of abnormal white blood cells. It's taken as a tablet once a day.

The side effects of imatinib are usually mild and should improve with time.

They can include:

  • feeling and being sick
  • swelling in the face and lower legs
  • muscle cramps
  • a rash
  • diarrhoea

Regular blood tests and occasional tests of your bone marrow will be carried out to check whether the treatment is working. If it does work, it will usually be taken for life.

Nilotinib

If you can't take imatinib or it doesn't work for you, a medicine called nilotinib may be recommended instead. It's also sometimes used as the first treatment for CML.

Nilotinib works in a similar way to imatinib and is taken as a capsule twice a day. If blood and bone marrow tests show the treatment is working, it's also usually taken for life.

Common side effects of nilotinib include:

If the side effects become particularly troublesome, temporarily stopping treatment usually helps to bring them under control. Treatment can then be resumed, possibly at a lower dose.

Dasatinib

If you can't take imatinib or nilotinib, or they don't work for you, a similar medicine called dasatinib may be recommended.

This is taken as a tablet once a day and is taken for life if blood and bone marrow tests show it's working.

Side effects of dasatinib can include:

  • an increased chance of picking up infections
  • tiredness
  • shortness of breath
  • diarrhoea
  • headaches
  • a rash

 

 

Bosutinib

Bosutinib is a similar medication to imatinib, nilotinib and dasatinib. It may be recommended if you can't take these medications, or you've tried them and they haven't helped.

Bosutinib is taken as a tablet once a day and is taken for life if blood and bone marrow tests show it is working.

Common side effects of bosutinib include:

  • diarrhoea
  • feeling and being sick
  • abdominal pain
  • a high temperature (fever)
  • a rash.

Ponatinib

Ponatinib is a similar medication to those mentioned above, but it's only recommended for people with a specific genetic change (mutation) called the T315I mutation.

It's taken as a tablet once a day and is taken for life if blood and bone marrow tests show it's working.

Side effects of ponatinib can include:

  • an increased risk of picking up infections
  • tiredness
  • shortness of breath
  • headaches
  • a rash
  • aching joints
  •  

Chemotherapy

 

Chemotherapy may be recommended if you can't take the medications above, or if CML has progressed to a more advanced stage. It may also be used while you're awaiting tests results to confirm you have CML.

Chemotherapy involves taking medication to kill the cancerous cells. Tablets are usually used first because they have fewer and milder side effects than chemotherapy injections.

Side effects can include:

  • tiredness
  • a rash
  • increased vulnerability to infection

If your symptoms persist or get worse, chemotherapy injections may be used. These have more side effects than tablets and they tend to be more severe.

In addition to the side effects mentioned above, side effects of chemotherapy injections can include:

  • feeling and being sick
  • hair loss
  • infertility
  • The side effects should pass after your treatment has finished, although there's a risk that infertility could be permanent.

Stem cell or bone marrow transplants

A stem cell or bone marrow transplant is the only potential cure for CML, but it's a very intensive treatment and isn't suitable for many people with the condition.

This is where donated cells called stem cells (which produce white blood cells) are transplanted into your body so you start to produce healthy white blood cells.

A stem cell transplant involves:

  • having high-dose chemotherapy and radiotherapy to destroy the cancerous cells in your body
  • removing stem cells from the blood or bone marrow of a donor – this will ideally be someone closely related to you, such as a sibling
  • transplanting the donor stem cells into one of your veins

The high doses of chemotherapy and radiotherapy can put an enormous strain on the body and can cause significant side effects and life-threatening complications.

Transplants are generally only considered in younger people with CML, people in good general health and ideally those with a sibling who can provide a donation, as it's more likely to be successful in these cases.

But in many cases of CML, the potential risks of transplantation far outweigh the potential benefits, particularly now that treatment with imatinib can often keep the condition under control for many years.

Self-help

Living with a serious, long-term condition such as CML can be very difficult.

You may find it useful to find out as much as you can about the condition and speak to others affected by it.