Doctors often can’t explain why a person gets cancer. But we do know what makes some cancers more likely.
Having a diet low in iodine
increases risk of thyroid cancer, but this is rare in Australia as iodine is added to salt and other foods.
Other factors that increase the risk of thyroid cancer include:
Radiation - this is a very important risk factor for thyroid cancer, either because of medical treatment (particularly low dose radiation treatment in childhood), or from environmental exposure such as atomic explosions or nuclear fallout
Having a non-cancerous (benign) thyroid disease - like an enlarged thyroid (goitre), thyroid nodules (adenomas) or inflammation of the thyroid (thyroiditis), or having one of these conditions in your family
A family history of thyroid cancer or an inherited gene change (mutation) in the RET oncogene (a protein coding gene)