A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, exposing the skin to strong sunlight is a risk factor for skin cancer. Smoking is a risk factor for lung cancer and many others.
But risk factors don’t tell us everything. Having a known risk factor, or even several risk factors, does not mean that you will get the disease. And many people who get the disease may not have had any known risk factors.
No specific inherited, environmental, or lifestyle risk factors have been strongly linked to thymoma or thymic carcinoma. Some studies have suggested a possible link with exposure to radiation to the upper chest area, but this has not been confirmed. The only known risk factors are age and ethnicity.
The risk of this type of cancer goes up with age. This type of cancer is rare in children and young adults, is seen more often in middle-aged adults, and is most common in those in their 70s.
In the US, this cancer is most common in Asian Americans and Pacific Islanders and least common in White and Latino people. It is more common in African American than in White people.