Leukemia is the most common cancer in pediatric patients, particularly in the Caucasian and Hispanic population. There are main types of leukemia, Acute Lymphocytic Leukemia (ALL) and Acute Myelogenous Leukemia (AML). Leukemia accounts for more than 33% of all pediatric cancers. This is why is particularly important to be aware of the risk factors that could predispose a child to develop leukemia .
A risk factor is something that increases the risk of somebody developing a disease. Risk factors for leukemia differ in children and adults. There are many known risk factors that are associated with leukemia in children, however, most of them are not things that can be changed. The risk factors can be categorized as those that have been
- shown through research to have a definite link with leukemia in children and
- those that may have a possible connection but it is not conclusive .
Definite Risk Factors
There are many genetic diseases that can predispose children to develop leukemia. As genetic diseases occur due to the presence of a DNA mutation, these can lead to the development of other disorders as well.
- Children with Down’s syndrome, which is an intellectual disability and is characterized by a number of birth defects including restricted growth and poor muscle tone, have a higher chance of developing a variety of cancers, one of which is leukemia.
- Another disease that can lead to leukemia is Bloom syndrome, which occurs due to a high number of abnormal chromosomes and can lead to a high incidence of osteosarcoma and Wilms tumor, in addition to leukemia .
- Fanconi anemia is a disease that affects the bone marrow as it does not make enough healthy blood cells or platelets . Due to lower immunity in patients with fanconi anemia, these children have a higher risk of developing of leukemia.
- Ataxia-telangiectasia, which affects the nervous and immune system, leads to lower immunity in children and a higher risk of developing cancer, particularly leukemia.
- Children with the disease neurofibromatosis type 1 have a higher chance of developing leukemia and brain cancers.
- Children with Wiskott-Aldrich syndrome also have a higher chance of developing symptoms of leukemia in children as this disease is characterized by the improper functioning of immune cells such as T cells and B cells.
- Klinefelter syndrome is a disease that affects male sexual development and has also been linked with leukemia.
- Children with Li-Fraumeni syndrome also have an increased risk of many cancers, including breast cancer, brain cancer, and leukemia.
- Finally, Schwachman-Diamond syndrome, which has been found to affect many parts of the body from the bone marrow to the skeletal system, has also been linked to leukemia as it is characterized by decreased amounts of all types of blood cells .
Children that have been exposed to high doses of radiation, usually due to radiation therapy for a different type of cancer, also have a higher risk of developing leukemia. Most children that develop leukemia due to radiation therapy develop AML, though some do also develop ALL. Furthermore, patients that have undergone chemotherapy for the treatment of previous cancer also have a higher risk of developing leukemia.
In addition to different diseases, having a sibling with leukemia also predisposes children to develop leukemia. In fact, children with a brother or sister with leukemia, have an overall 2-3% higher risk of developing leukemia than the general population. The risk is even higher in identical twins. Higher birth weight, particularly greater than 8.9 pounds, has also been linked to a higher risk of developing leukemia, particularly ALL .
Inconclusive risk factors
There are certain risk factors that have been associated or linked to leukemia that have been shown to exist through some research but there is not enough evidence to conclusively classify them as risk factors.
- One of these risk factors is the exposure of the pregnant mother or a small child to low-level radiation through imaging tests such as x-rays, CT scans, or MRI scans . This particular risk factor has been shown to lead to ALL in some studies, however, the possibility of developing leukemia from such an exposure is very low.
- A few studies have also shown that exposure to the electromagnetic field, or EMFs, have been linked to increased incidence of developing signs of leukemia in children, but this is controversial .
- Furthermore, if a child or the pregnant mother are exposed to pesticides then the child may have a higher chance of developing pediatric leukemia. However, there are a number of chemicals that compose pesticides and only some of them may cause leukemia.
- There is also a mild association between a parent’s history of smoking and developing leukemia as well as exposure to second-hand smoke during pregnancy. Second-hand smoking seems to have a particular relationship with the development of ALL.
- Some studies have also demonstrated that drinking while pregnant can be related to the incidence of pediatric AML .
- Exposure to benzene for adults, particularly in the workplace, has also been associated with being a risk factor for pediatric leukemia in their offspring.
- Finally, the mother’s exposure to paint has been linked to pediatric leukemia, though more studies that need to be conducted on this subject .