Symptoms and Diagnosis
More than 90 percent of thyroid nodules are not harmful or cancerous. An individual may not be aware of the nodule’s presence until it starts to grow, resulting in an enlarged thyroid. A doctor may feel it, however, when he or she carefully examines the thyroid gland.

Nodules should be checked by a doctor. Tests can usually tell if a nodule is harmless or harmful and which treatment would be best. A nodule may be cancerous if the lymph nodes under the jaw are swollen and if it grows quickly, feels hard, and causes pain. Cancerous nodules also tend to cause hoarseness or difficulty with swallowing or breathing.

If a patient has had radiation treatment around the head or neck areas, he or she should tell his or her doctor because this can increase an individual’s chances of having nodules and cancer.
Among people who have thyroid nodules, thyroid cancer is found in about 8 percent of men and 4 percent of women. To determine whether a nodule may be harmful and whether the patient should undergo thyroid cancer treatment, the doctor may perform any number of tests. These include the following:
  • Ultrasound (sonogram). Technicians use a machine to show sound waves that map out a picture of the thyroid gland and any nodules contained within it.
  • Fine-needle aspiration biopsy. In this test, a thin needle is inserted into the nodule to remove cells and/or fluid samples from the nodule for examination under a microscope.
  • Thyroid scan. This is a radiation detector that scans over the neck, after a tiny amount of radioactive substance is administered, to reveal whether the nodule is functioning (producing hormones).
  • Blood and other laboratory tests. Tests include those that measure levels of thyroid-stimulating hormone, as well as antibodies and possibly calcitonin. Calcitonin is a hormone known to participate in calcium and phosphorus metabolism. The major source of calcitonin is from the parafollicular cells in the thyroid gland. High calcitonin levels may indicate medullary thyroid cancer, a cancer originating from the parafollicular cells.
Treatments
Again, only about 5 percent of thyroid nodules are cancerous. If you have thyroid cancer, please remember that most patients recover well with proper thyroid cancer treatment. Thyroid cancers need to be removed by surgery, after which radioactive iodine therapy may be needed to destroy any remaining thyroid cells.
Other types of nodules, even if they are not cancerous, may also need to be removed. Most specialists recommend a total rather than partial removal of the thyroid gland. The thyroid gland and the nodules within it are removed by surgery (thyroidectomy) with use of thyroid hormone replacement treatment afterward.
Following surgery and subsequent radioactive iodine therapy, patients with thyroid cancer require monitoring for many years. The monitoring varies among patients but typically includes tests for thyroid function and serum thyroglobulin levels (a tumor marker), as well as possibly radiologic studies to include sonograms, CT scans, MRI scans and radioactive scans. The tests will vary based on the type of tumor.
Some nodules when scanned will show that they are collecting greater than normal amounts of radioactive iodine. These nodules are overfunctioning nodules, are referred to as “hot” on a scan, and are usually not cancerous. They can, however, produce extra amounts of thyroid hormones and cause hyperthyroidism. Such overfunctioning nodules may be surgically removed or treated with radioactive iodine.
If a nodule has fluid in it, it is called a cyst. To treat it, the doctor will probably drain it or monitor it for change. If these nodules return, then they may need to be removed. Nodules that have only fluid are usually non-cancerous, but nodules that have some fluid and some solid matter can be cancerous and need to undergo thyroid cancer treatment.