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Most cases of chronic lymphocytic leukaemia (CLL) are detected during blood tests carried out for another reason.

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

Your GP may:

  • ask about your symptoms and your medical and family history
  • carry out a physical examination to check for problems such as swollen glands and a swollen spleen
  • send off a blood sample for testing

If your GP thinks you could have CLL, you'll be referred to a hospital doctor called a haematologist, a specialist in blood disorders, for further tests.

Some of the tests you might have are outlined below.

The main test used to help diagnose CLL is a type of blood test called a full blood count.

This is where the number and appearance of the different blood cells in a sample of your blood are checked in a laboratory.

An abnormally high number of unusual white blood cells (lymphocytes) can be a sign of CLL. A detailed examination of these cells can usually confirm the diagnosis.

You may also have: 

These tests can check for problems caused by CLL, such as swollen glands or a swollen spleen, and help rule out other possible causes of your symptoms.

Sometimes the haematologist may recommend removing a sample of your bone marrow (bone marrow biopsy) so they can examine it under a microscope to check it for cancerous cells.

The sample is removed using a needle inserted into your hip bone. Local anaesthetic is normally used to numb the area where the needle is inserted, although you may experience some discomfort during the biopsy.

The procedure will last around 15 minutes and you should not need to stay in hospital overnight. You may have some bruising and discomfort for a few days afterwards.

In some cases, removing and examining a swollen lymph gland can help confirm a diagnosis of CLL. This is known as a lymph node biopsy.

The gland is removed during a minor operation carried out under either local or general anaesthetic, where you're asleep. You will not usually need to stay in hospital overnight.

After the operation, you'll be left with a small wound that will be closed with stitches.

Tests may also be carried out on your blood and bone marrow samples to check for any unusual genes in the cancerous cells.

Identifying unusual genes in these cells can help your doctors decide how soon you should start treatment and which treatment is best for you.

Some treatments for CLL do not work as well in people with certain abnormal genes in the affected cells.