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Risk factors for Hodgkin lymphoma
A risk factor is something that increases the risk of developing cancer. It could be a behaviour, substance or condition. Most cancers are the result of many risk factors. But sometimes Hodgkin lymphoma develops in people who don’t have any of the risk factors described below.
Hodgkin lymphoma affects men slightly more often than women. It is most common in younger adults (mid-teens through the 30s) and in people age 55 and older.
The following are risk factors for Hodgkin lymphoma. Most of the known risk factors are not modifiable. This means that you can’t change them. Until we learn more about these risk factors, there are no specific ways you can reduce your risk.
Risk factors are generally listed in order from most to least important. But in most cases, it is impossible to rank them with absolute certainty.
Research shows that there is no link between exposure to radiation and a higher risk of Hodgkin lymphoma.
Known risk factors
There is convincing evidence that the following factors increase your risk for Hodgkin lymphoma.
Long-term infection with the Epstein-Barr virus (EBV) is a risk factor for Hodgkin lymphoma. Many people are infected with EBV, but only some of them develop a long-term infection.
First-degree relatives (parent, brother, sister or child) of a person with Hodgkin lymphoma have an increased risk of developing the disease. Siblings of the same sex may have a greater risk than people in the general population. It is unclear whether the increase in risk is due to genetics alone or a combination of genetics and being exposed to factors in the environment.
The human immunodeficiency virus (HIV) is the virus that causes AIDS. HIV weakens the body’s immune system and may leave people vulnerable to certain types of cancer, including Hodgkin lymphoma. The risk of developing Hodgkin lymphoma is 10 times higher in people with HIV than in people without the virus.
Find out more about HIV.
The following factors have been linked with Hodgkin lymphoma, but there is not enough evidence to show they are known risk factors. More research is needed to clarify the role of these factors for Hodgkin lymphoma.
A number of studies have suggested that genetics may play a role in developing Hodgkin lymphoma. But little is known about the genetics of Hodgkin lymphoma. Although close relatives of people with Hodgkin lymphoma are at increased risk of the disease, the reasons for this higher risk are not known.
Epstein-Barr virus can cause infectious mononucleosis (mono). Researchers in some parts of the world have found a connection between infectious mononucleosis and the risk of Hodgkin lymphoma, particularly in young adults. Studies have shown that young adults who have had infectious mononucleosis have a 2-4 times greater risk of developing Hodgkin lymphoma than those who have not had it. Experts are not sure whether infectious mononucleosis is an independent risk factor or a sign of infection with EBV.
People with certain autoimmune diseases have an increased risk of Hodgkin lymphoma. These diseases include:
- rheumatoid arthritis
- systemic lupus erythematosus
- ulcerative colitis
- immune thrombocytopenic purpura
People with poor immunity may have a higher risk for Hodgkin lymphoma. Poor immunity may be caused by conditions such as:
- severe combined immunodeficiency (SCID)
- hyperimmunoglobulin M syndrome
- congenital (present at birth) immunodeficiency
- organ transplant or allogeneic (from a donor) bone marrow transplant
Studies suggest that current smokers have a higher risk of developing Hodgkin lymphoma. They may also have an increased risk of tumours that contain the Epstein-Barr virus.
Socio-economic status and types of families
There is an increased risk of Hodgkin lymphoma in young adulthood through middle age linked to the following factors:
- higher social class
- fewer siblings and playmates
- early birth order
- less crowded housing
Some researchers suggest that the reason for this may be linked to getting a common childhood infection at a later age than usual because they were not exposed to the infection during childhood.
It isn’t known whether or not the following factors are linked with Hodgkin lymphoma. It may be that researchers can’t show a definite link or that studies have had different results. More research is needed to see if the following are risk factors for Hodgkin lymphoma.
- previous surgery to remove the tonsils or the appendix
- education level of the mother
- physical activity
- exposure at work to wood dust or chemicals, including trichloroethylene (TCE) and farming chemicals
Questions to ask your healthcare team
To make the decisions that are right for you, ask your healthcare team questions about risks.
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