Causes and prevention of thyroid cancer

The exact cause of thyroid cancer in most people is unknown. Some risk factors can increase your chance of developing it.

These include:

  • If you get certain benign thyroid diseases. These are not cancer but include an enlarged thyroid (goitre), thyroid nodules (adenomas) or an inflamed thyroid (thyroiditis)
  • If you eat very little iodine in your diet, you are at risk
  • If you have been exposed to radiation, you can develop thyroid cancer many years later. For example, this happened to people who lived near the nuclear plant at Chernobyl in the Ukraine, after it exploded in 1986
  • If you had radiotherapy as a child, you may be more at risk in later life of developing thyroid cancer
  • If you have a faulty gene known as RET gene, it may cause medullary thyroid cancer. This is very rare and inherited from your family

Remember an overactive or underactive thyroid does not increase your risk of developing thyroid cancer. If you think you may be at risk, first talk to your family doctor (GP) about your concerns. He or she may advise you to visit a specialist.

Call our National Cancer Helpline

Freephone 1800 200 700 to talk to a specialist cancer nurse
It's open Monday-Thursday from 9am to 7pm and Friday from 9am to 5pm