Acute myeloid leukaemia (AML) is a form of leukaemia, that starts in the bone marrow (which is the inner soft part of the bone that produces the new blood cells), but can advance into the blood and some other parts of the body like the central nervous system, liver, lymph nodes, spleen, and testicles.
Acute myeloid leukaemia affects the development of the myeloid cells (a group of white blood cells) the generally mature into red blood cells, white blood cells, and platelets.
AML is the most common type of acute leukaemia. There are 8 subtypes of acute myeloid leukaemia which makes it one of the main aspects that differentiate it from other types of leukaemia. The subtypes are differentiated based on the cell that leukaemia is developed from, which include
- M0- Undifferentiated acute myeloblastic leukemia (Myeloblastic)- start in immature forms of white blood cells.
- M1- Acute myeloblastic leukemia with minimal maturation (Myeloblastic)- start in immature forms of white blood cells.
- M2- Acute myeloblastic leukemia with maturation (Myeloblastic)- start in immature forms of white blood cells.
- M3- Acute promyelocytic leukemia (Promyeloctic)- start in immature forms of white blood cells.
- M4- Acute myelomonocytic leukemia (Myelomonocytic)- start in immature forms of white blood cells.
- M5- Acute monocytic leukemia (Monocytic)- start in immature forms of red blood cells.
- M6- Acute erythroid leukemia (Erythroleukemia)- start in immature forms of red blood cells.
- M7- Acute megakaryoblastic leukemia (Megakaryocytic)- starts in immature forms of cells that make platelets.
The symptoms of acute myeloid leukaemia include fever, frequent infections, anaemia, easy bruising or bleeding, joint & bone pain.
If you observe any of the above symptoms or signs, your doctor will prescribe the diagnostic procedure to determine the condition. The diagnostic procedure like sample tests, lab tests, and imaging tests that include,
- Blood sample: Generally the first test done, the blood is drawn from the vein in arm.
- Bone marrow sample: the sample can be obtained from 2 methods, by bone marrow aspiration is where a hollow needle is inserted into the bone, and the bone marrow is removed. Where as in bone marrow biopsy a small part of bone is removed along with bone marrow.
- Spinal fluid: This procedure is also called as lumbar puncture or spinal tap. In this method the cerebro spinal fluid (CSF) is removed from the spinal cord. This procedure is only recommended when there are signs of acute myeloid leukaemia spreasind to CNS system. Also, lumbar puncture procedure is used a treatment procedure to deliver the chemotherapy drugs.
- Complete blood count (CBC) & Peripheral blood smear: CBC test measures the amounts of different cells in the blood, such as the RBCs, WBCs, and platelets. Peripheral blood smear, helps in identifying the changes in the numbers and the appearance of different types of blood cells.
- Routine cell exams under microscope: Samples of blood, bone marrow, or CSF are observed under a microscope to look and classify the WBC according to their size, shape, and other traits.
- Cytochemistry: The cells in the sample are exposed to chemical stains (dyes) that react with only some types of leukemia cells. These stains induce change in colour that can be observed under a microscope, to differentiate.
- Flow cytometry & Immunohistochemistry: The cells in the samples are treated with antibodies (proteins), that fasten to specific proteins on cells. These methods are used for immunophenotyping leukaemia cells, that helps in classification of acute myeloid leukaemia. In Flow cytometry the cells are observed under microscope where as a special equipments are used in Immunohistochemistry.
- Chromosome tests: These tests observe the chromosomes. Cytogenetics test is a type of the chromosome tests, where the chromosomes are observed under microsome to observe changes in chromosome, which include deletion, inversion, addition or duplication, and translocation. Fluorescent in situ hybridization (FISH) observes for specific changes in certain parts of the DNA with the help of dyes. Polymerase chain reaction (PCR) is a sensitive test that can also find the changes that are too small to be observed under a microscope. It is helpful in finding gene changes that are in only a few cells, making it good for finding small numbers of leukemia cells in a sample, it is prescribed after or during the treatment to evaluate the treatment and making any further changes in the treatment also.
- X-ray: A regular x-ray are suggested if any infection to other organs is suspected.
- Computed tomography (CT) scan: Geenerally CT scans uses x-ray to get the cross-sectional image of the focused organ. Sometimes CT scan can also be used to guide a biopsy needle if abscess is suspected. Also, sometimes PET scan is used along with CT scan for more precise diagnosis as PET use radioactive sugars to capture a picture of the regions of high radioactivity as the cancer cells absorb large amounts of sugar, then a CT scan is used to obsereve the region more detailed.
- Magnetic resonance imaging (MRI) scan: MRI scan gives precise images of the soft tissues like the CT scan, but instead of usinf x-rays like for CT scan, radio-wavws are used for MRI scan.
- Ultrasound: This procedure uses sound waves to make the image of the internal organs or masses. Ultrasound can be used to obsereve at lymph nodes near the surface of the body or to look inside your abdomen for enlarged lymph nodes or organs such as the liver, spleen, and kidneys. Also, it is sometimes used to guide the needle inside swollen or enlarged lymph nodes for a biopsy.
If you are diagnosed with acute myeloid leukaemia (AML), your oncologist/ doctor will discuss the treatment options that can be based on the acute myeloid leukaemia subtype, other prognostic factors, age and your overall health status.