While medical researchers are unsure of the exact causes of acute myelogenous leukemia (AML), certain risk factors have been identified that increase the chances of an individual developing AML during his or her lifetime. Although the following risk factors have been associated with increased risk for AML, they do not guarantee that the disease will develop. In fact, some people develop AML without any identified risk factors.
Genetic Disorders:
Certain inherited disorders can increase the risk for developing AML. These conditions are quite rare, and include:
- Ataxia-telangiectasia. This is an inherited disorder that appears first in early childhood with symptoms of increased infections, lack of balance, and slurred speech. This disorder also weakens the immune system in about 70% of cases.
- Blackfan-Diamond syndrome. Also referred to as Blackfan-Diamond anemia, this disorder is a form of progressive anemia that is observed in the first year of life.
Chronic Myeloproliferative Disorders:
"Myeloproliferative" means the abnormal production of large numbers of bone marrow cells that produce red blood cells, granulocytes, or platelets. All myeloproliferative disorders can progress to leukemia. These disorders include:
- Idiopathic myelofibrosis. Myelofibrosis is a condition in which fibroblasts in the bone marrow produce too much fibrous connective tissue and crowd out blood-producing stem cells.
- Polycythemia vera. Polycythemia vera is a condition in which the body produces too many red blood cells, thickening the blood and increasing the risk of blood clots leading to heart attack and stroke.
Smoking:
According to the American Cancer Society, as many as 1 in 5 cases of AML are caused by smoking. Smoking introduces toxic, cancer-causing substances to the body through the lungs, and these substances are then spread throughout the body in the bloodstream. Smoking is the only known lifestyle factor that increases the risk of developing AML.
Chemical Exposure:
Exposure to certain toxic chemicals can increase the risk of developing AML. This includes long-term workplace exposure to the industrial solvent benzene, and exposure through chemotherapy to drugs such as mechlorethamine, procarbazine, chlorambucil, etoposide, teniposide and anthracylines. A case of AML that is determined to be caused by prior chemotherapy is referred to as a "secondary" leukemia, and these usually occur within 10 years of the initial treatment.
Radiation Exposure:
Although the risks of developing chemotherapy-related AML are increased when chemotherapy is combined with radiation therapy, low-dose radiation such as that used in scans, x-rays, or radiation therapy has not been proven to significantly increase the risk of developing AML. However, high-dose radiation exposure (such as the radiation associated with an atomic bomb or a nuclear reactor accident like Chernobyl) are associated with a greatly increased risk of developing AML within the 6 to 8 years following the exposure.
Sources:
"Acute Myelogenous Leukemia." UCSD Medical Center. Accessed: 15 November 2008. http://health.ucsd.edu/cancer/patcare/leuk_lymph/leukemia/acute-myelogenous.htm.
"What Are the Risk Factors for Acute Myeloid Leukemia (AML)?" American Cancer Society. Accessed: 14 November 2008. http://www.cancer.org/docroot/CRI/content/CRI_2_4_2x_What_Are_the_Risk_Factors_for_Acute_Myeloid_Leukemia_AML.asp?sitearea=. "What Are Thrombocythemia and Thrombocytosis?" National Heart, Lung, and Blood Institute. Accessed: 14 November 2008. http://www.nhlbi.nih.gov/health/dci/Diseases/thrm/thrm_what.html
"What Is Fanconi Anemia?" National Heart, Lung, and Blood Institute. Accessed: 14 November 2008. http://www.nhlbi.nih.gov/health/dci/Diseases/fanconi/fanconi_whatis.html
"What Is Polycythemia Vera?" National Heart, Lung, and Blood Institute. Accessed: 14 November 2008. http://www.nhlbi.nih.gov/health/dci/Diseases/poly/poly_whatis.html
