Etiology and risk factors of AML
Like many kinds of cancers, the
etiology for most cases of AML is unclear, and currently there is no known major
cause of AML. However, there are multiple risk factors that are associated with
AML. Generally, known risk factors account for only a small number of observed
cases. These risk factors are explained and listed below.
Smoking is
the only proven lifestyle-related risk factor for AML. It is known that smoking
is linked to multiple types of cancer, specifically lung, mouth, throat and
larynx cancers, but few people realize that smoking affects cells that don’t
come into direct contact with tobacco. The tobacco that is absorbed by the
lungs can spread into the bloodstream to many parts and cells of the body.
Genetic disorders and constitutional genetic defects are important risk factors associated
with AML. For example, children with Down syndrome have a 10-fold to 20-fold
increased likelihood of developing acute leukemia.
Certain chemical exposures increases the risk of developing AML. Long-term
exposure to high levels of benzene, a solvent used in oil and gasoline-related
industries, rubber industries, and chemical plants.
Certain chemotherapy drugs can also increase the risk of developing AML. Many
patients are diagnosed with secondary AML, which is often developed after
receiving chemotherapy for separate cancers different from AML.
Radiation exposure in high doses, such as being exposed to nuclear reactor accidents or
atomic bombs increases the risk of developing cancer. Radiation treatment for
cancer has also been linked to an increased risk in developing AML.
Certain blood disorders and myelodysplastic syndrome
(MDS) are also linked to the
development of AML. The blood disorders include chronic myeloproliferative
disorders such as polycythemia vera, essential thrombocythemia, and idiopathic
myelofibrosis. Sometimes treatment of these disoders include radiation or
chemotherapy, which further increases the risk of developing AML. Patients with
MDS have low blood cell counts and abnormal cells in the blood and bone marrow,
which can evolve overtime into AML.
Family history and having a close relative, such as a parent or sibling with AML
increases your risk of developing AML. However, most cases of AML are not
thought to have a strong genetic link.
Older age is
considered to be more common in diagnoses of AML, although AML can even be
diagnosed in childhood.
Male gender
has been found to be more of a risk factor than female gender, even though the
cause of this is unclear.
Disease progression and morbidity of AML
The word “acute” in acute
myeloid leukemia denotes to the disease’s rapid progression. As discussed in
the first blog post, myeloid leukemia involved the myeloid cells in white blood
cells located in the bone marrow. When these cells are abnormal and fail to
develop into proper mature white blood cells, patients’ immune systems are incredibly
compromised, and regular colds or preventable illnesses become serious fast.
Pneumonias can be fatal in patients with AML.
Sources
1. Deschler,
B., & Lubbert, M. (2006, October 1). Acute myeloid leukemia: Epidemiology
and etiology. Retrieved from
http://onlinelibrary.wiley.com/doi/10.1002/cncr.22233/full
2. American
Cancer Society. (2014, December 1). What are the risk factors for acute myeloid
leukemia?