What causes thyroid cancer, and what are risk factors of thyroid cancer?
No one knows the exact causes of thyroid cancer. Doctors can seldom explain why one person gets this disease and another does not. However, it is clear that thyroid cancer is not contagious. No one can “catch” cancer from another person. Research has shown that people with certain risk factors are more likely than others to develop thyroid cancer. A risk factor is anything that increases a person’s chance of developing a disease. The following risk factors are associated with an increased chance of developing thyroid cancer: • Radiation. People exposed to high levels of radiation are much more likely than others to develop papillary or follicular thyroid cancer. One important source of radiation exposure is treatment with x-rays. Between the 1920s and the 1950s, doctors used high-dose x-rays to treat children who had enlarged tonsils, acne, and other problems affecting the head and neck. Later, scientists found that some people who had received this kind of treatment developed thyroid