Thyroid cancer is a disease that you get when abnormal cells begin to grow in your thyroid gland . The thyroid gland is shaped like a butterfly and is located in the front of your neck. It makes hormones that regulate the way your body uses energy and that help your body work normally.
Thyroid cancer is an uncommon type of cancer. Most people who have it do very well, because the cancer is usually found early and the treatments work well. After it is treated, thyroid cancer may come back, sometimes many years after treatment.
What causes thyroid cancer?
Experts don't know what causes thyroid cancer. But like other cancers, changes in the DNA of your cells seem to play a role. These DNA changes may include changes that are inherited as well as those that happen as you get older.
People who have been exposed to a lot of radiation have a greater chance of getting thyroid cancer.
A dental X-ray now and then will not increase your chance of getting thyroid cancer. But past radiation treatment of your head, neck, or chest (especially during childhood) can put you at risk of getting thyroid cancer.
Researchers from Brighton (England), Cambridge (England) and Kuwait have demonstrated that thyroid cancer risk increases as the number of dental x-rays taken grows. The researchers report that the incidence rates of thyroid cancer have doubled from 1.4 per 100,000 in 1975 to 2.9 per 100,000 in 2006 in the UK.
They stress that several factors are probably involved in the thyroid cancer increase, and that sensitive diagnostic techniques should not be considered to account for all of it. Further research is needed.
The research team was led by Dr Anjum Memon, senior lecturer and consultant in public health medicine at Brighton and Sussex Medical School (England), a partnership between Brighton and Sussex universities, and NHS (National Health Service) Brighton and Hove (England).
This study has been published in the medical journal Acta Oncologica.
The thyroid gland, which is located in the neck, is exposed to radiation from many dental x-rays. This gland is sensitive to ionizing radiation, especially in children. The researchers inform that dental radiography, a source of low-dose diagnostic radiation, is frequently ignored as a potential risk to the thyroid gland.
The scientists studied 313 patients in Kuwait, they all had thyroid cancer. In Kuwait dental treatment is free. Compared to other countries, such as the UK, the incidence of thyroid cancer in Kuwait is high.
They said the results of their study, although the largest case-control study on the subject, "should be treated with caution because the data were necessarily based on self-reporting by the participants. Comprehensive historical dental x-ray records were not available from the clinics."
The researchers believe their study provides good evidence to warrant further research in settings where historical dental x-ray records are available and where radiation doses can be estimated.