Thyroid nodules are growths or lumps that develop within the thyroid gland, which is a butterfly-shaped gland located in the neck that produces hormones that regulate metabolism. Most thyroid nodules are benign (non-cancerous), but some can be cancerous.

The relationship between thyroid nodules and cancer is that about 5% of thyroid nodules are malignant, meaning they are cancerous. Thyroid cancer is a relatively rare type of cancer, but it is important to have thyroid nodules evaluated by a doctor to determine if they are cancerous or not.