Causes and Risk Factors
For most people who have acute myeloid leukemia (AML), there are no obvious reasons (risk factors) why they developed the disease.
Researchers have identified potential risk factors, including:
- repeated exposure to the chemical benzene, which damages the DNA of normal marrow cells. According to the Agency for Toxic Substances and Disease Registry, despite the fact that petroleum products contribute to the majority of benzene in the atmosphere, half of the total national personal exposure to benzene comes from cigarette smoke. Benzene is also found in certain industrial settings; however, the strict regulation of its use has decreased benzene exposure in the workplace.
- certain genetic disorders such as Down syndrome, Fanconi's anemia, Shwachman syndrome and Diamond-Blackfan syndrome
- past chemotherapy or radiation treatments for other cancers
- a history of other blood cancers or disorders, such as polycythemia vera, myelofibrosis, primary thrombocythemia and myelodysplastic syndromes
You can't catch AML from someone else.
Age and AML
People aged 60 years and older are more likely to develop the disease than younger adults.
How Does AML Develop?
AML results from acquired changes in the DNA (genetic material) of a developing marrow cell. Once the marrow cell becomes a leukemic cell, it multiplies into 11 billion or more cells. These cells, called "leukemic blasts," do not function normally. However, they grow and survive better than normal cells.
The presence of the leukemic blasts blocks the production of normal cells. As a result, when AML is diagnosed, the number of healthy blood cells (red cells, white cells and platelets) is usually lower than normal.
Several things can happen if AML isn't treated:
- Low numbers of red cells mean they can no longer supply an adequate amount of oxygen, leading to anemia.
- The immune system can't guard against infection effectively because of a lack of neutrophils (a type of white cell), a condition called neutropenia.
- Low numbers of platelets can cause bleeding and easy bruising with no apparent cause, a condition called thrombocytopenia.
AML progresses rapidly without treatment.