Risks for chronic leukemia

Last medical review: February 2024

Some things can affect your risk, or chance, of developing cancer. Certain behaviours, substances or conditions can increase or decrease the risk. Most cancers are the result of many risks. But sometimes cancer develops in people who don't have any risks.

Chronic leukemia includes 2 types of leukemia – chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML). Some risks may be different for CLL and CML, and some may be the same.

The risk of developing chronic leukemia increases with age. CLL usually occurs in people older than 50 and CML usually occurs in people older than 65.

Men develop chronic leukemia more often than women. We need more research and can't say at this time what the risk is for transgender, non-binary and gender-diverse people.

The following can increase your risk for chronic leukemia.

Family history of CLL

There is convincing evidence that having a family history of CLL increases your risk of developing the disease. Your risk is higher if one of your first-degree relatives (your parents, siblings or children) has been diagnosed.

High levels of radiation

There is convincing evidence that coming into contact with high levels of radiation, such as radiation from nuclear reactor accidents, is a risk for CML.

Possible risks

There are some things that may increase your risk for chronic leukemia. More research is needed to know for sure that they are risks. The following have been linked with CLL, CML or both:

coming into contact with pesticides over a long period of time (CLL)
coming into contact with Agent Orange, a mixture of herbicides used during the Vietnam War (CLL)
farming (CLL)
having obesity (CLL and CML)
breathing in benzene (CLL and CML)
breathing in formaldehyde (CML)
previous radiation therapy (CML)
coming into contact with radiation at work (CML)

Understanding your cancer risk

To make the decisions that are right for you, ask your doctor questions about risks. Learn how cancer can be prevented and what you can do to reduce your risk.

Canadian Cancer Society | Société canadienne du cancer

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