Diagnostic tests for AML
A combination of blood and bone marrow tests will help your doctor confirm the diagnosis and work out the subtype of acute myeloid leukaemia (AML) you have.
Learn more about these tests to diagnose AML:
- Blood tests
- Bone marrow tests
- Further tests
Your doctor will take a sample of blood and send it to a laboratory for a full blood count (FBC). This will show whether leukaemia cells are present in the blood and whether the levels of blood cells are different from what would be expected in a healthy person.
Blood cells develop in your bone marrow, so your doctor will want to check your bone marrow for signs of leukaemia. Samples of bone marrow are usually collected in two ways:
- bone marrow aspiration – the doctor uses a thin needle to remove a small amount of fluid (aspirate) from the bone marrow, usually from the hipbone (pelvic bone)
- bone marrow biopsy or trephine – the doctor uses a slightly larger needle to remove a small amount of bone and marrow.
You will be given a local anaesthetic to numb the area, pain relief that you inhale (commonly known as the green whistle) or light sedation to help you relax. Pain medicine may make you feel drowsy, so ask a family member or friend to drive you home afterwards. Although it can take up to 30 minutes to prepare for a bone marrow test, the actual procedure takes only a few minutes.
The bone marrow samples (biopsy) are sent to a laboratory. A specialist called a pathologist will do tests on the samples to work out the subtype of acute leukaemia. These tests may include:
This test looks for markers or signals called antigens that are found on the surface of cells. Looking at the patterns of antigens can help your doctor work out whether you have AML and what subtype it is.
Cancer changes the genes of affected cells. These gene changes do not pass through families. They are only in the structure of the leukaemia cells, not in normal cells.
Tests looking for changes in the genes involved in leukaemia are becoming more standard. The commonly tested genes are known by abbreviations such as FLT3, NPM1, CEBPA, IDH1 and IDH2. The results of these genetic tests help doctors decide on suitable treatment options and work out the chance of the AML coming back (recurring) after a period of improvement (remission).
Tests known as FISH (fluorescence in situ hybridisation) and PCR (polymerase chain reaction) are used to look for the most common gene changes in AML. The PCR test may also be used to check how well treatment has worked and if further treatment is needed.
You may have other tests to find out more about the AML, your general health and how well your organs are working.
A chest x-ray is taken to check the heart and lungs, and to see whether there are enlarged lymph nodes in the chest. Enlarged lymph nodes are sometimes seen in people with AML.
Lactate dehydrogenase (LDH)
This enzyme is released into the blood when cells are damaged or destroyed. A blood test can check LDH levels, which will usually be raised in people with AML.
Human leukocyte antigen (HLA) typing
If having a stem cell transplant may be an option, your blood or bone marrow sample will be tested for human leukocyte antigen (HLA). HLA is found on most cells in your body – it helps your immune system recognise which cells belong in your body. A transplant can usually only go ahead if the stem cell donor is a close match to your HLA type. This is why your close relatives may also have an HLA test.
A blood test to check for infections such as HIV (human immunodeficiency virus) or hepatitis.
Gated heart pool scan
This scan is used to see how well the heart is working. A small amount of your blood is taken, mixed with some radioactive material and injected back into your body. A special camera known as a gamma camera takes pictures of the blood being pumped by your heart.
A computerised tomography (CT) scan uses x-rays and a computer to create cross-sectional pictures of the body. It can show if your lymph nodes are affected and if your spleen is enlarged. A dye (contrast) may be injected beforehand to make the pictures clearer.
This scan uses echoes from soundwaves to create a picture of the body’s organs on a screen.
A magnetic resonance imaging (MRI) scan uses a large magnet and radio waves to take detailed cross-sectional pictures of the body. Tell your doctor if you have a pacemaker, as the magnetic waves can interfere with some pacemakers. In some cases, a dye (contrast) is injected beforehand to make the pictures clearer.
Before having scans, tell the doctor if you have any allergies or have had a reaction to contrast during previous scans. You should also let them know if you have diabetes or kidney disease, or if you arepregnant or breastfeeding.
A/Prof John Moore (Conjoint UNSW), Senior Staff Specialist Haematology, Department of Haematology and Bone Marrow Transplant, Kinghorn Cancer Centre, St Vincent’s Hospital; Glynda Blomson, Consumer; Kevin Bloom, Senior Social Worker, Haematology and Bone Marrow Transplant, Royal North Shore Hospital; Sharon Frazer, Consumer; Prof Angela Hong, Radiation Oncologist, Chris O’Brien Lifehouse, and Clinical Professor, The University of Sydney; Yvonne King, 13 11 20 Consultant, Cancer Council NSW; Karen Maddock, Clinical Nurse Consultant – Haematology, Westmead Hospital.
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