Thyroid nodules are very common, occurring in 15 to 65 percent of people of all ages. They occur in both women and men but are especially common in women (50 percent of women ages 50 or older have had a thyroid nodule).
Usually patients and their physicians first notice thyroid nodules during a routine physical exam of the neck area, and sometimes they are found incidentally during a radiographic evaluation of the neck (such as a CT scan, X-ray, MRI, or ultrasound). These studies are usually ordered to evaluate the patient for another condition—perhaps for whiplash after a motor vehicle accident, for a chronic cough, or for patients having a carotid artery ultrasound.
Although the vast majority of thyroid nodules are benign, the physician should evaluate a significant thyroid nodule, as approximately 5 to 10 percent of thyroid nodules are cancerous. In general, a thyroid nodule is considered “significant” if it is 1 cm or larger and/or presents concerning features on ultrasound.
Large nodules are often removed for a number of reasons. Benign large thyroid nodules may cause pressure symptoms and can lead to the formation of goiter. Thyroid nodules that produce excess thyroid hormone also need to be removed. Lastly, some thyroid nodules are large enough that standard diagnostic approaches prevent accurate assessment of the possibility of cancer; and therefore, they also need to be surgically removed.
Diagnosing Thyroid Nodules
The typical workup for thyroid nodules includes an initial ultrasound and a blood test to assess TSH (thyroid stimulating hormone, produced by the pituitary gland). For nodules that are greater than 1 cm and/or appear suspicious on the initial ultrasound, a fine needle biopsy will be ordered.
If the nodule cannot be felt during the office physical exam, an ultrasound-guided biopsy will be performed by a radiologist who will localize the nodule and obtain a good sample. These biopsies help the physician gain a better understanding of the cytologic (cell make-up), biomarker, and molecular makeup of the nodule and help to determine whether surgery is needed. These studies are performed by our Radiology Department and the results are analyzed by the Cytopathology Department at Mass. Eye and Ear/Mass General.
At the conclusion of this workup, our surgeons will determine if surgery is recommended and also the extent of surgery needed.
Surgery may include removing one side of the thyroid or the entire thyroid, and it may also include removal of affected lymph nodes in the neck around the thyroid. In thyroid nodules that are either suspicious for cancer or show definite evidence of thyroid cancer, thyroid surgery is the recommended treatment. Some thyroid nodules without definite evidence of cancer may also require surgical treatment. The surgeon will individualize the treatment plan after a thorough review of all the data.
The workup described for thyroid nodules follows the national guidelines set by the American Thyroid Association (ATA). Division Director Dr. Gregory Randolph plays a significant role in the leadership of the ATA and served on the 2014 American Thyroid Association guidelines taskforce writing group for thyroid nodules and differentiated thyroid cancer.
There is no medical treatment for thyroid nodules. If a decision is made that the thyroid nodule needs to be removed, surgical treatment is recommended.
Typically surgery is performed through a small incision at the base of the neck and involves removal of one lobe of the thyroid or the entire thyroid gland. The surgery usually takes 2 to 3 hours, and most patients are watched carefully in the hospital overnight. The pain is often minimal and most patients take 4 to 7 days off from work to recuperate.
Some patients will need to take thyroid replacement medication long-term after surgery. This medication promotes normal thyroid function and normal metabolism after surgery so that patients are able to return to normal. Additionally, if there is evidence of cancer, some patients may require the administration of postoperative radioactive iodine treatment. The thyroid surgeon and medical endocrinologist will communicate and make a decision together after surgery regarding these potential postoperative interventions.
An important risk to consider with any type of thyroid surgery is the potential loss of voice, swallowing, and, sometimes, breathing function. Surgeon experience and measures taken to preserve the nerves in this complex area are imperative to a good outcome. These measures include fiber-optic preoperative laryngeal exam, voice analysis, and intraoperative nerve monitoring.
Another risk of surgery is a potential compromise of parathyroid function. The parathyroid glands are very small glands that sit at the periphery of the thyroid gland and should be handled carefully during thyroid surgery, as they have an important role in calcium metabolism. Our surgeons are experts on parathyroid anatomy and preservation. Occasionally patients experience a temporary loss of parathyroid function from surgical manipulation and may require short-term supplementation with calcium pills until the function of these glands recovers.