Benign Thyroid Conditions
Thyroid nodules are solid lumps arising in the thyroid gland. The thyroid gland, at the base of the neck, produces thyroid hormone, which regulates body growth and metabolism.
Nodules usually grow slowly over many years. They appear singularly or in clusters (benign nodular goiter) and usually are not detectable until they have grown to at least one centimeter in size.
The greatest concern of a solitary nodule is the possibility of cancer, although this is uncommon. The vast majority of solitary nodules are cysts or benign tumors (adenomas), which affect about 4 percent of the adult population.
Nodules are classified according to their production of thyroid hormone. "Warm" nodules mimic normal thyroid cells in this regard. "Hot" nodules overproduce thyroid hormone and are virtually always benign. "Cold" nodules underproduce thyroid hormone.
What Causes Thyroid Nodules?
- The cause of thyroid nodules is unknown, but incidence is higher among people who received x-ray treatment to the thyroid area in infancy or childhood. Women are affected more often than men.
Symptoms of Thyroid Nodules
- A solid, usually painless lump in the front of the neck, near the windpipe or Adam’s apple
- Feelings of nervousness, weight loss and heartbeat irregularity
- Having a feeling of fullness
- Muscle weakness/tremors
- A throaty harshness
- Sleep disturbances
- Enlargement of the thyroid gland (Goiter)
- Increased appetite
- Redness of the skin
- Heat sensitivity
- Infrequent, scant menstrual periods
- Vision problems or eye irritation
- Intolerance to cold
- Bounding pulse
- Clammy skin
- Dry, coarse skin and hair
- Frequent, heavy menstrual periods
- Possibly, in the case of “hot” nodules, symptoms of hyperthyroidism
- Substantial swelling in the neck in cases of benign nodular goiter
- Rarely, breathing or swallowing difficulty, if nodules grow large enough to become obstructions
Prevention of Thyroid Nodules
- There is no known way to prevent thyroid nodules.
Diagnosis of Thyroid Nodules
- Patient history including any radiation treatments in infancy or childhood.
- Physical examination to determine whether the lump is solitary or in a cluster.
- Thyroid function tests to measure thyroid hormone levels. Patients with hyperthyroidism usually need a scan to determine whether their nodule(s) are hyperfunctioning or not.
- Ultrasound scans to identify cysts.
- Fine-needle biopsy (use of a small-gauge needle and syringe to take a tissue sample for examination under a microscope) is used to rule out cancer.
- Blood and other laboratory tests that determine the thyroid-stimulating hormone level, and antibodies, and possibly calcitonin.
How to Treat Thyroid Nodules
- If a needle biopsy shows no evidence of cancer and thyroid function tests are normal, regular follow-up examinations and thyroid function tests are all that is required.
- If the nodule is a fluid-filled cyst, needle drainage may be done.
- Hot nodules associated with hyperthyroidism are treated with radioactive iodine or surgery.
- Thyroidectomy is recommended if cancerous cells are detected in a needle biopsy.
- Treatment for hypothyroidism may subsequently be needed if excess thyroid tissue is removed or destroyed by radioactive iodine therapy.
- If the findings are equivocal on fine-needle biopsy, thyroid hormone may be administered to observe whether the nodule shrinks over the ensuing six to 12 months.
When to Call a Doctor
- Call a doctor as soon as possible if you detect an unusual lump in your neck. A complete evaluation is imperative.
Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference
Simeon Margolis, M.D., Ph.D., Medical Editor
Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50
Updated by Remedy Health Media