Factors that may increase the risk of acute lymphocytic leukemia include the following:
Previous cancer treatments. Children and adults who have undergone certain types of chemotherapy and radiation therapy for other types of cancer may have a higher risk of developing acute lymphocytic leukemia.
Radiation exposure. People exposed to very high levels of radiation (such as survivors of nuclear reactor accidents) have a higher risk of developing acute lymphocytic leukemia.
Genetic disorders. Certain genetic disorders, such as Down syndrome, are associated with an increased risk of developing acute lymphocytic leukemia.
Having a sibling with acute lymphocytic leukemia. People who have a brother or sister (whether twins or not) with acute lymphocytic leukemia have a higher risk of developing the disease.
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