Medical Edge Newspaper Column

Most Causes Of An Enlarged Thyroid Are Benign

July 10, 2006
DEAR MAYO CLINIC:
What problems are associated with an enlarged thyroid?

ANSWER:
The thyroid gland, a small butterfly-shaped gland just below your Adam's apple, is responsible for producing thyroid hormone. Many aspects of metabolism -- including heart rate, body temperature and the speed at which you burn calories -- are regulated by thyroid hormone. When faced with a thyroid problem, your physician has two concerns:

Thyroid gland size. Normally weighing just an ounce, the thyroid may become enlarged for several reasons -- some serious, some not.

Most causes of an enlarged thyroid are benign. Thyroid cancer does not commonly cause the entire gland to become enlarged. Because of its location near the windpipe and esophagus, an enlarged thyroid could create difficulties with coughing, hoarseness, breathing or swallowing.

For people older than 65, benign nodules on the thyroid often cause the enlargement. Although most nodules are benign, your physician may elect to perform a simple biopsy to ensure there is no reason for concern.

If symptoms are bothersome or worrisome, nodules can be surgically removed or, in some cases, treated with radioactive iodine. This therapy is taken orally and destroys thyroid cells, reducing thyroid size. This approach is safe, but may result in an underactive thyroid, necessitating hormone replacement therapy.

If you have symptoms of an enlarged thyroid, work with your doctor to confirm a diagnosis and determine if treatment is needed. Even when the gland is enlarged, it could still be working properly. If symptoms aren't bothersome, your doctor may suggest a wait-and-see approach.

Thyroid function. The gland can overproduce or underproduce hormones. Both can cause health concerns. Underproduction or overproduction of hormones could be related to an enlarged thyroid or inflammation of the thyroid. Blood tests can confirm the diagnosis.

Treatment could include hormone replacement for an underactive thyroid or medication including radioactive iodine to normalize hormone levels for an overactive thyroid. If the thyroid is inflamed, aspirin or corticosteroid medications may help.

-- Michael Whitaker, M.D., FRCPC, Endocrinology, Mayo Clinic, Scottsdale, Ariz.