A thyroid nodule is a growth (lump) in the thyroid gland. The thyroid gland is located at the base of the neck.
Overview, Causes, & Risk Factors
Thyroid nodules are growths of cells in the thyroid gland. These growths can be noncancerous (benign) or cancerous (malignant). Some nodules are fluid-filled (cysts), while others are made of thyroid gland cells. Sometimes, what feels like one nodule will actually be a collection of small nodules.
Thyroid nodules are more common in women than in men. A person’s chance of a thyroid nodule increases with age.
Only a few thyroid nodules are cancerous. (See: Thyroid cancer)
The following characteristics increase the chances that a thyroid nodule is cancerous:
- A hard nodule
- A nodule that is stuck to nearby structures
- Family history of multiple endocrine neoplasia type II
- Family history of thyroid cancer, especially medullary thyroid carcinoma
- Hoarse voice due to vocal cord paralysis
- Age — younger than 20 years or older than 70
- History of radiation exposure to the head or neck
- Male gender
Causes of thyroid nodules are not always found, but can include:
- Hashimoto’s disease
- Iodine deficiency
Review Date : 4/29/2009 Reviewed By : David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Deborah Wexler, MD, Assistant Professor of Medicine, Harvard Medical School, Endocrinologist, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. © 1997- 2010 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.