Chronic lymphocytic leukaemia - Diagnosing chronic lymphocytic leukaemia

Most cases of chronic lymphocytic leukaemia are discovered during unrelated routine blood tests.

However, you should visit your GP if you display the typical symptoms of leukaemia. They will ask about your symptoms, as well as your medical and family history.

Your GP will also carry out a physical examination to check for swollen glands, a swollen spleen and any signs of abnormal bleeding. You may also be asked to have a blood test.

Full blood count

If your GP suspects leukaemia, they'll refer you to a haematologist (a doctor who specialises in conditions that affect the blood).

A blood sample will be taken and sent to a laboratory for a full blood count. Here, the different types of blood cells will be counted and the appearance of the cells checked.

An abnormally high number of lymphocytes (white blood cells) will suggest you have chronic lymphocytic leukaemia.

However, to confirm the diagnosis, the haematologist will need to carry out a procedure known as immunophenotyping. This involves examining the lymphocytes in detail to distinguish chronic lymphocytic leukaemia from other conditions that can also cause a high lymphocyte count.

This test is often carried out in a specialist laboratory and the results will usually be available in one to two weeks.

X-ray and ultrasound scan

You may also need to have some other tests, such as a chest X-ray, ultrasound scan or computerised tomography (CT) scan (see below).

A chest X-ray can be used to see whether there are any changes in your tissues or organs, and to rule out other possible causes of your symptoms.

Your doctor will also give you a physical examination to check the size of your spleen, and you may need to have an ultrasound scan to see the spleen in more detail.

Bone marrow biopsy

In some cases, the haematologist may want to look at a sample of your bone marrow.

A bone marrow biopsy involves taking a small sample of bone marrow to examine under a microscope. It is usually carried out under a local anaesthetic.

The haematologist will numb an area of skin at the back of your hip bone, before removing a sample of bone marrow using a needle. You may experience some discomfort during the procedure and have some bruising and discomfort in the area where the sample was taken for a few days afterwards.

The procedure will take around 15 minutes to complete and you shouldn't need to stay in hospital overnight.

The bone marrow sample will be examined for cancerous cells. If these are present, the specific type of chronic leukaemia can also be determined.

Genetic tests

Genetic tests can also be carried out on blood and bone marrow samples. A test known as a fluorescence in situ hybridisation (FISH) test can be used to help identify abnormalities in the leukaemia genes.

Gene abnormalities are easy to identify because the affected genes glow. Doctors are able to use FISH to identify abnormal genes in the cells of about 80% of people with chronic lymphocytic leukaemia.

Identifying gene abnormalities in this way is very useful because it allows treatments to be targeted more effectively.

Further tests

A number of additional tests may be recommended to provide more information about the progress and extent of the leukaemia.

For example, if you've been diagnosed with chronic leukaemia, further biopsies may be carried out on any enlarged lymph nodes you have.

This is known as a lymph node biopsy and it can help determine whether the leuakemia is a more active variant, sometimes called a Richters transformation, or whether any other conditions are present.

Sometimes, your haemotologist may recommend that you have a CT scan, where a series of X-rays are taken and a computer is used to create detailed three-dimensional (3D) images of the inside of your body.

A CT scan can be used to check your lymph nodes and organs for abnormalities.