What increases my risk of thyroid cancer?

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The cause of thyroid cancer is unknown. But there are certain things called risk factors that can increase your chance of developing the disease. These include:

  • Age: Most cases occur in people over 40. 
  • Gender: Women are more at risk than men.
  • 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 have very little iodine in your diet, you are at risk.
  • Radiation: If you have been exposed to radiation from a nuclear plant, you can develop thyroid cancer many years later.
  • If you had radiotherapy as a child, you may be more at risk in later life of developing thyroid cancer.
  • Family history of  thyroid cancer: You are more at risk if a family member has had medullary thyroid cancer.
  • Inherited faulty gene: You may be at risk if you inherit faulty genes. For example, the RET gene may cause medullary thyroid cancer. Also, the bowel condition called familial adenomatous polyposis (FAP) may lead to thyroid cancer.

An overactive or underactive thyroid does not increase your risk of developing thyroid cancer. 

Having a risk factor doesn’t mean you will get cancer. Sometimes people with no risk factors get the disease. If you’re worried, talk to your GP or talk to one of our cancer nurses. Call our Support Line on 1800 200 700 or visit a Daffodil Centre.

Reducing your risk of thyroid cancer

The most important thing you can do to reduce your risk of thyroid cancer is to:

  • Get checked with your GP if you have a family history of medullary thyroid cancer.

Read more about cancer risk-reduction tips

For more information

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1800 200 700

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