Acute myeloid leukemia (AML) is a cancer that occurs in the blood and the marrow of the bones. Marrow is sponge-like material inside the bones that produces blood cells. AML specifically affects the white blood cells of the body, causing them to form abnormally. The numbers of abnormal cells grows rapidly. According to the National Bone Marrow Program, there are nearly 11,900 new cases of AML each year.
AML is caused by abnormalities in the DNA that controls the development of the cells in your bone marrow. In AML, the bone marrow creates white blood cells that are immature. These abnormal cells eventually become leukemic white blood cells called myeloblasts. The abnormal cells build up and replace healthy cells. This causes the bone marrow to stop functioning properly, making the body more susceptible to infections. It is not clear exactly what causes the DNA mutation. Some doctors believe it may be related to exposure to certain chemicals, radiation, and even drugs used for chemotherapy.
Your risk for developing AML goes up as you age. AML is most common in those over the age of 65. It is also more common in men than women. Cigarette smoking is thought to increase your risk of developing AML. If you work in an industry where you may have been exposed to chemicals like benzene you are also at risk. Your risk also goes up if you have a blood disorder like myelodysplasia or a genetic disorder like Down syndrome.
These risk factors do not mean you will necessarily develop AML. At the same time, it is possible for you to develop AML without having any of these risk factors.
In its early stages, the symptoms of AML may resemble the flu, and you may have a fever and fatigue. Other symptoms include:
- bone pain
- frequent nosebleeds
- bleeding and swollen gums
- shortness of breath
- unexplained weight loss
- heavier than normal periods in women
Your doctor will perform a physical exam and check for swelling of the liver, lymph nodes, and spleen. Your doctor will also order blood tests to check for anemia and to determine your white blood cell levels.
While a blood test may help your doctor determine whether there is a problem, a bone marrow test or biopsy is needed to fully diagnose AML. A sample of bone marrow is taken by inserting a long needle into the hipbone. The sample is sent to a lab for testing. Your doctor may also do a spinal tap, or lumbar puncture, which involves withdrawing fluid from the spine with a small needle. The fluid is checked for the presence of leukemia cells.
Treatment for AML occurs in two phases:
Remission Induction Therapy
Remission induction therapy uses chemotherapy to kill leukemia cells in the body. Most patients stay in the hospital during treatment because chemotherapy also kills healthy cells, raising your risk for infection and abnormal bleeding. In a rare form of AML called promyelocytic leukemia, anti-cancer drugs like arsenic trioxide or all-trans retinoic acid may be used to target specific mutations in leukemia cells. These drugs kill the leukemia cells and stop the unhealthy cells from dividing.
Consolidation therapy is crucial for keeping AML in remission and preventing a relapse. The goal of consolidation therapy is to destroy any remaining leukemia cells. You may require a stem cell transplant for consolidation therapy. Stem cells are often used to help the body generate new and healthy bone marrow cells. The stem cells may come from a donor. But if your leukemia has previously gone into remission, your doctor may have removed and stored some of your own stem cells for a future transplant, known as an autologous stem cell transplant.
Stem cells from a donor have a higher risk for complications than a transplant comprised of your own stem cells. A transplant of your own stem cells however, has a higher risk for relapse because some old leukemia cells may be present in the sample retrieved from your body.
If you work around hazardous chemicals or radiation, make sure to wear any and all available protective gear to limit your exposure.
With prompt treatment, remission is highly likely in most patients. Once all signs and symptoms of AML have disappeared, you are considered to be in remission. If you are in remission for more than five years, you are considered cured of AML.
If you find that you have symptoms of AML, schedule an appointment with your physician to discuss them. You should also seek immediate medical attention if you have any signs of infection or a persistent fever.