Your doctor will ask you about your medical history, risk factors, symptoms if you have any. He/she will also perform a physical examination.
If your doctor thinks that you may have AML, then he/she will want to obtain some of the following tests in order to confirm the diagnosis:
- Complete blood count:
A complete blood count (or CBC for short) provides information about the number of red blood cells, white blood cells, and platelets present in the blood. As explained earlier, it is very common for patients with AML to present with low red cell, white cell and/or platelet counts. However, having low blood cell counts does not necessarily mean that someone has AML. Other blood diseases such as myelodysplastic syndrome (MDS) or aplastic anemia can also cause low blood cell counts.
A “peripheral blood smear” is also done using a small sample of the blood collected for a CBC test. The blood sample is spread on a glass slide and visually inspected under the microscope to look specifically for the presence of myeloblasts or leukemia cells.
- Bone marrow aspiration and biopsy:
This procedure consists of removing a small amount of blood from the bone marrow (this is the “aspiration” part) followed by removing a small piece of the bone marrow (this is the “biopsy” part).
Usually, this procedure is done in the doctor’s office or the patient’s room (if the patient is already in the hospital) using local anesthesia to numb the skin and bone underneath.
The back of the hipbone (also known as “pelvic bone”) is the preferred site for performing bone marrow aspiration and biopsy. On very few occasions, the breastbone can be used instead of the hipbone to collect a bone marrow aspirate. However, a bone marrow biopsy is NEVER collected from the breastbone marrow because of the risk of damaging blood vessels or the heart located right behind the breastbone.
- Flow cytometry:
Blood collected from the bone marrow aspirate is sent for a test called “flow cytometry”. This test checks for the presence specific markers on the surface of leukemia cells. Because leukemia cells (myeloblasts) have some resemblance to normal myeloid precursor cells, they have some markers in common. By checking the presence of these markers, doctors can make sure that leukemia cells belong to the myeloid lineage, thus confirming the diagnosis of AML.
- Cytogenetic evaluation:
In the nucleus of each cell, DNA is tightly packaged into thread-like structures called chromosomes. Our chromosomes carry our genetic information in the form of genes. Cytogenetic evaluation in AML consists of several tests used to determine whether leukemia cells have any abnormalities in their chromosomes. For example, some leukemia cells can lose a part of or even an entire chromosome. Other types of leukemia cells can have one or more extra chromosomes. Sometimes, a part of a chromosome can break and reattach to another chromosome and this is referred to as “translocation”.
You may hear several terms such as “Karyotype analysis”, “Polymerase Chain Reaction” (PCR) or “Fluorescent In Situ Hybridization” (FISH). These are all different methods we can use to look for potential chromosomal abnormalities in leukemia cells.
Performing a cytogenetic evaluation is very important because it helps doctors know what is the prognosis (or outlook) of someone with AML AND it helps them decide what is the best treatment for that person.
The use of cytogenetic evaluation to determine the prognosis (outlook) of AML will be discussed in more detail in the “Classification” section
The use of cytogenetic evaluation for treatment decision-making is further discussed in “Treatment” section of this booklet.
- Molecular analysis:
This test looks for abnormalities (mutations) in specific genes found in leukemia cells. Such genes include FLT3, NPM1, CEBPA and c-KIT. Like changes in the chromosomes of leukemia cells, mutations in these genes detected can also determine the prognosis (outlook) and guide the choice of treatment for someone with AML.
- Lumbar puncture (or spinal tap):
This procedure is not routinely done in patients with AML. It is only performed if the doctor suspects that leukemia cells may have spread to the brain or spinal cord. During this procedure, a small sample of the fluid surrounding the brain and spinal cord called Cerebrospinal fluid (or CSF) is collected. The test can be done in the doctor’s office or the patient’s room (if the patient is already in the hospital) using local anesthesia to numb the skin. A needle is inserted between two bones in the spine and into the CSF around the spinal cord. A sample of the fluid is collected through the needle into a syringe and is then visually inspected under the microscope to look for the presence of myeloblasts or leukemia cells.
Human leukocyte antigen (HLA) typing/matching is another test that the doctor may request once the diagnosis of AML is made. It is usually obtained if an allogeneic hematopoietic stem cell transplantation is being considered as an option for AML treatment (more details on HLA typing/matching can be found in the “Treatment” section of this booklet).