Acute myeloid leukemia (AML) is a cancer of the blood and bone marrow – the spongy tissue inside the bones where blood cells are formed.
The word “acute” means that the disease is progressing quickly. It affects a group of white blood cells called myeloid cells which normally develop into different types of mature blood cells such as red blood cells, white blood cells and thrombocytes.
Symptoms
General signs and symptoms of early-stage acute myeloid leukemia can mimic the symptoms of flu or other similar diseases. Signs and symptoms can vary depending on the type of blood cell that is affected. Signs and symptoms of acute myeloid leukemia:
- Fever
- Bone pain
- Lethargy and fatigue
- Shortness of breath
- Pale skin
- Frequent infections
- Easy bruising
- Unusual bleeding, such as frequent nosebleeds and bleeding gums
When to See a Doctor
If you notice any signs or symptoms that seem unusual or worry you, see a doctor. Acute myeloid leukemia gets worse quickly if not treated, so prompt diagnosis is helpful.
Causes
Acute myeloid leukemia is caused by DNA damage in cells that develop in the bone marrow. Bone marrow produces immature cells that develop into leukemic white blood cells. These abnormal cells are not able to function properly and can build up and overpower the healthy cells.
Risk Factors
Factors that may increase the risk of acute myeloid leukemia include:
- Age- The risk of acute myeloid leukemia increases with age. Acute myeloid leukemia is most common in adults aged 65 years and older.
- Sex- Men are more likely to develop acute myeloid leukemia than women.
- Previous cancer treatment- People who have had certain types of chemotherapy and radiation therapy, or treatment for pediatric acute lymphocytic leukemia (ALL), may have a higher risk of developing AML.
- Radiation exposure- People exposed to very high levels of radiation, such as survivors of accidents in nuclear reactors, have an increased risk of AML.
- Hazardous chemical exposure- Exposure to certain chemicals, such as benzene, which is found in unleaded gasoline and is used in the chemical industry, is also associated with an increased risk of AML.
- Smoking- AML is associated with tobacco smoke, containing benzene and other known cancer-causing chemicals.
- Other diseases of blood- People who have had another blood disorder, such as myelodysplastic syndrome, polycythemia vera or thrombocythaemia, have a higher risk of AML.
- Genetic disorders-Certain genetic disorders, such as Down’s syndrome, are associated with an increased risk of AML.
Many people with AML have no known risk factors, and many people who have risk factors do not develop this form of cancer.
Tests and Diagnosis
If you have signs or symptoms of acute myeloid leukemia, the doctor may recommend diagnostic tests:
Blood tests
In most people with acute myeloid leukemia, there are too many white blood cells, insufficient red blood cells and insufficient thrombocytes. The presence of immature cells that are normally found in the bone marrow, but not yet circulating in blood, is another indicator of acute myeloid leukemia,
Marrowbone
A blood test can indicate leukemia, but usually bone marrow test is needed to confirm the diagnosis. During a bone marrow biopsy, a sample of bone marrow is taken by a needle. Usually, the sample is taken from the thigh. The sample is then sent to a laboratory for testing.
Lumbar puncture
In some cases, it may be necessary to remove some of the fluid around the spinal cord to check leukemic cells. If your doctor suspects leukemia, you may be referred to a doctor who specializes in cancer (oncologist) or a doctor who specializes in blood disorders (hematologist).
Treatments and Drugs
Treatment of acute myeloid leukemia depends on several factors, including disease subtype, age, your overall health and your desires. Generally, treatment falls into two phases:
Induction therapy
The purpose of the first stage of treatment is to kill the leukemia cells in blood and bone marrow. However, induction usually does not destroy all the leukemic cells, so further treatment is required to prevent recurrence of the disease.
Consolidation therapy
Consolidation therapy does not differ significantly from the induction therapy in this phase of treatment and is aimed at destroying the remaining leukemia cell. It is considered crucial to reducing the risk of recurrence.
Chemotherapy
Chemotherapy is the main form of induction therapy, although it can also be used for consolidation therapy. Chemotherapy uses chemicals to kill cancer cells in the body. Generally stay in hospital is required during chemotherapy because it destroys many normal blood cells in the process of killing leukemic cells. If the first cycle of chemotherapy does not cause remission, it can be repeated.
Other drug therapy
Arsenic trioxide and retinoic acid are drugs used alone or in combination with chemotherapy. These drugs cause the leukemia cells to mature and die, or to cease to multiply.
Stem cell transplantation
Transplantation of stem cells, also called bone marrow transplant, helps to re-establish healthy stem cells to replace unhealthy cells. Before the stem cell transplant, you will receive very high doses of chemotherapy or radiation therapy to destroy the bone marrow that produces cancerous cells. Then you will receive an infusion of stem cells from a compatible donor. You can also receive your own stem cells if you have been in remission and removed healthy stem and stored them for future transplantation.