Thyroid nodules are abnormal growths or lumps in the thyroid gland. Most nodules are not cancerous and do not cause problems. Many do not even need treatment.
Only about 5% of thyroid nodules are cancerous. Cancerous nodules have to be surgically removed.
In rare cases, thyroid nodules cause thyroid problems. Hyperthyroidism can develop when a nodule makes too much thyroid hormone and causes the thyroid gland to be overactive or work too hard.
Experts do not know the exact cause of thyroid nodules. But, they doknow that people who have been exposed to radiation have a greater chance of developing thyroid nodules. Theyknow that thyroid nodules tend to run in families.
Most thyroid nodules are so small that you do not know you have one. If you have a big nodule, you may be able to feel it or you may notice that your neck is swollen. In rare cases, you:
Feel pain in your throat or feel like you throat is full
Have a hard time swallowing
Have a hard time breathing
Feel nervous, have a fast heartbeat, sweat a lot, lose weight or have other symptoms of hyperthyroidism
Feel tired or depressed, have memory problems, be constipated, have dry skin, feel cold or have other symptoms of hypothyroidism