Common Thyroid Cancer Symptoms
A painless lump in the neck is the most common of the thyroid cancer symptoms. Fortunately less than 10% of lumps in the thyroid gland are cancerous, and usually a needle biopsy of the lump will help determine whether a lump is cancer or not. Rarely thyroid cancers can be diagnosed at advanced stage, and can spread to the neck, lungs, bones or other organs.
The exact causes of thyroid cancer in most people are not known. The presence of benign thyroid diseases slightly increases an individuals risk of thyroid cancer. This includes an enlarged thyroid (goitre), thyroid nodules (adenomas), or inflammation of the thyroid gland (thyroiditis). The more common thyroid conditions of an over- or under-active thyroid (hyperthyroidism and hypothyroidism) do not increase your risk.
A poor diet that contains large amounts of butter, cheese and meat may increase your risk of thyroid cancer. Large amounts of fresh fruit and vegetables may help to reduce your risk. People who eat very little iodine in their diet are more likely to develop thyroid cancer.
In a very small number of people, medullary thyroid cancer may be due to an inherited faulty gene called the RET oncogene. Family members of someone with medullary thyroid cancer can be tested to see if they have inherited an abnormal RET gene.
Exposure to radiation also increases your thyroid cancer risk. This may be due to radiotherapy given in childhood, or to unusually high levels of radiation in the environment; for example, in the areas surrounding Chernobyl in the Ukraine, following the nuclear power explosion of 1986. Thyroid cancer can develop many years after exposure. However, only a small number of thyroid cancers are caused by radiation exposure.