Bone marrow test
You may have this test to find out more information about the CML. Bone marrow is spongy tissue and fluid that is inside some of your bones. It makes blood cells.
A doctor or specialist nurse removes an area of bone marrow from your hip bone. A specialist doctor looks at the tissue under a microscope.
You usually have the test in the outpatient department of the hospital. You are awake for the test but you have a local anaesthetic to numb the area.
Some people may have medicine to make them drowsy (sedation). Some hospitals may use gas and air (Entonox) to help relax you instead of sedation.
Types of biopsy
There are 2 main types of bone marrow test:
- bone marrow aspiration
- bone marrow trephine biopsy
Aspiration means the doctor or nurse sucks some liquid bone marrow up into a syringe.
A bone marrow trephine means that they remove a 1 or 2cm core of bone marrow in one piece.
You usually have both of these tests done at the same time. They give some of the same information to the doctor, but there are differences. The bone marrow trephine shows the structure of the bone marrow inside the bone, whereas the aspiration takes just the bone marrow cells.
Preparing for your bone marrow test
Your nurse or doctor will tell you how to prepare for the bone marrow test if you are in hospital. If you are an outpatient your appointment letter will explain what you need to do.
You are usually able to eat and drink beforehand if you aren't having sedation.
Take your medicines as normal unless told otherwise. If you are taking any blood thinning medicines, you might need to stop these before the test. Your doctor will tell you when to stop taking them.
What happens?
Your doctor gives you information about the procedure and asks you to sign a consent form. This is a good time to ask any questions you have.
You change into a hospital gown and lie on your side with your knees tucked up into your chest.
Your doctor or nurse cleans the area with some antiseptic fluid, which can feel cold. You then have an injection into the skin over the biopsy site to numb the area. They put a thin needle through the skin into the hip bone. This might be uncomfortable but this only lasts a short time.
Your doctor or nurse sucks a small amount of liquid bone marrow into the needle, using a syringe. You feel a pulling sensation when they start drawing the bone marrow cells out.
They take the needle out and put in a second one if you're having a trephine biopsy as well. The aim is to get a small amount of marrow out in one piece.
The whole test takes around 30 minutes.
What to expect when you have a bone marrow test
Your bone marrow is the spongy substance in the centre of the bones where the blood cells are made.
You may have a bone marrow test if you have a cancer which affects the bone marrow such as leukaemia, lymphoma or myeloma. if your doctor thinks your bone marrow may contain cancer cells that have spread from another type of cancer or you have a non-cancerous condition.
There are two types of tests. A bone marrow aspiration which takes some bone marrow cells and a bone marrow biopsy which takes samples of the bone marrow and gives more information about its structure.
Usually your doctor takes the sample from the back of your hip bone but you can have a bone marrow aspiration from your breast bone.
You have the test lying on a couch. You may have a sedative beforehand to make you sleepy. The doctor then injects some local anaesthetic to numb the area.
For a bone marrow aspiration they put a needle through your skin and into your bone. Then using a syringe they draw out some liquid bone marrow. You may feel a pulling sensation as they do this.
For a biopsy your doctor uses a slightly bigger needle to take the sample of bone marrow. They turn and push this needle to get the sample. This can be painful as the needle goes in but it doesn’t last for long.
You usually go home about half an hour after the test. If you had sedation you need to wait until you are fully awake. This can take a few hours.
Afterwards your hip will ache for a few days. Taking painkillers helps.
You may also have some bruising. Rarely you may have some slight bleeding from the site. Press on it if you do and if it doesn’t stop contact the hospital.
There is a small risk of infection. Tell your doctor if you have a temperature or the biopsy area becomes red and sore.
You may have some tingling in your leg which will also wear off with time.
After your bone marrow test
If you have sedation, you need to stay at the hospital for a few hours until it has worn off. And you need someone to take you home and stay with you overnight.
You usually go home the same day if you're feeling well enough.
You have a dressing over the site, which you should keep on for 24 hours.
Possible risks from bone marrow test
A bone marrow test is very safe and any risks are small.
During the procedure there is a very small risk of damage to nearby structures, but this is very rare.
Bleeding
It's not unusual to have a small amount of bleeding from the area where the needle went in. If you notice any heavy bleeding, apply pressure to the area. If it doesn't stop, contact the hospital.
Bruising
Sometimes blood leaks out of the vein and collects under your skin. This can look like a small dark swelling under the skin (haematoma). Pressing hard once the needle is removed can help
Infection
There is a small risk of getting an infection in the wound. Tell your doctor if you have a temperature or if the area becomes red and sore.
Pain
Some people feel uncomfortable and have pain after the local anaesthetic has worn off. Your nurse will tell you what painkillers to take. If you have severe pain or it's getting worse then you should contact the hospital.
Tingling in your leg
You may have some tingling in your leg which wears off with time.
Getting your results
You should get your results within 1 or 2 weeks at a follow up appointment.
Waiting for test results can be a worrying time. You can contact your specialist nurse if you’re finding it hard to cope. It can also help to talk to a close friend or relative about how you feel.
Contact the doctor that arranged the test if you haven't heard anything after a couple of weeks.
DNA analysis
Some further laboratory tests may be carried out on your bone marrow sample. These tests are also called chromosome analysis. Your haematologist may order these tests to look for changes (abnormalities) in your chromosomes. The tests are called cytogenetic tests or molecular analysis.
About 95 out of every 100 people with CML (95%) have an abnormality called the Philadelphia chromosome. This is when a gene called the ABL1 gene on chromosome 9 breaks off and sticks to a gene called the BCR gene on chromosome 22. It produces a new gene called BCR-ABL1. Testing for this genetic change can diagnose CML. Doctors also use it to see how well treatment for CML is working.
The BCR-ABL1 gene causes the cell to make too much of a protein called tyrosine kinase. This protein encourages leukaemia cells to grow and multiply. The main treatment for CML works by blocking this protein.
