Being diagnosed with CML

CML usually causes very few symptoms in its early stages. So people are often diagnosed by chance when they have a blood test for another reason.

If your doctor suspects you have CML, they’ll arrange for you to see a haematologist – a doctor who specialises in treating blood diseases. You’ll have more blood tests and, if the results of these show leukaemia cells in your blood, the haematologist will organise different tests to find out more about the leukemia. These will also help your specialist plan your treatment. 

You will usually have a bone marrow sample to check for abnormal white blood cells in your bone marrow. You blood and bone marrow will also be examined to see if you have the Philadelphia chromosome. This is called cytogenetic testing.

You may also have:

  • a chest x-ray to check your heart and lungs
  • an ultrasound scan to build a picture of your organs.

At the hospital

The haematologist will ask you about any illnesses or health problems you’ve had. They will also examine you to check whether your lymph nodes, spleen or liver are enlarged. You will also have more blood tests to check the number of different cells in your blood (a full blood count) and to look for leukaemia cells.

If the blood test shows there are leukaemia cells in your blood, the haematologist will arrange further tests to find out which type of leukaemia you have and its extent. The results of these tests will help them plan your treatment.


Having tests

Bone marrow sample

A doctor or nurse takes a small sample of bone marrow from the back of the hip bone (pelvis), or occasionally the breast bone (sternum). The sample is sent to a laboratory to be checked for abnormal white blood cells. A haematologist can tell which type of leukaemia you have by identifying the type of abnormal white cell.

Bone marrow sampling
Bone marrow sampling

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The procedure can be done on the ward or in the outpatients department. It takes about 20–30 minutes in total, but taking the bone marrow sample only takes a few minutes.

Before the bone marrow sample is taken, you’ll be given a local anaesthetic injection to numb the area. You may also be offered a short-acting sedative to reduce any pain or discomfort during the test.

The doctor or nurse passes a needle through the skin into the bone. They then draw a small sample of liquid from inside the bone marrow into a syringe. This is called a bone marrow aspirate. It can feel uncomfortable for a few seconds when the liquid marrow is drawn into the syringe.

You may also have small core of marrow taken (a trephine biopsy). The doctor or nurse passes a thicker needle through the skin into the bone marrow. When they take the needle out, it contains a small core of bone marrow.

You may feel bruised after having a sample of bone marrow taken, and have an ache for a few days. You can ease this by taking mild painkillers.

Cytogenetic tests

These are tests that look at chromosomes through a microscope:

Philadelphia chromosome test

The blood and bone marrow sample will be analysed to look for the Philadelphia chromosome. This will help doctors decide on the best treatment for you.

Polymerase chain reaction (PCR) test

This is a blood test that detects the BCR-ABL gene, which is usually present in CML. It’s a very sensitive test and can detect tiny amounts of leukaemia that can be missed by other tests. Doctors use the PCR test to see how you are responding to treatment.


Further tests

Chest X-ray

This uses X-rays to take a picture of your chest, to check your lungs and heart.

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