What is a thyroid nodule?
A thyroid nodule is a growth or mass within the thyroid gland. The vast majority of thyroid nodules do not cause any problems with swallowing, foreign body sensation, or pain. If there are multiple nodules it is known as a multinodular goiter. A multinodular goiter is fairly common and often causes no problems and many times only gets diagnosed if there is some type of ultrasound or scan performed of the head and neck for some other reason. Thyroid nodules need to be of a certain size to be felt in the neck, usually larger than a centimeter and often around 2 centimeters to be easily felt, but they still may not be felt if the patient is overweight or a nodule is lower in the neck, behind the collar bones (clavicles) or breast bone (sternum).
Single Thyroid Nodule or Dominant Thyroid Nodule
If a single nodule or dominant nodule in a multinodular goiter is identified, this is a case where more investigation is necessary to make sure it is not cancerous. Patients would typically be referred to an otolaryngologist with experience in head and neck surgery to evaluate the nodule and to determine if a biopsy and possibly surgical removal is appropriate. Sometimes, though, this will be done by an endocrinologist who would then refer the patient to an otolaryngologist or general surgeon in cases requiring removal of the nodule.
How are thyroid nodules evaluated?
The evaluation of a thyroid nodule typically consists of laboratory tests, a thyroid ultrasound, and possibly a fine-needle aspiration biopsy (FNA) of the nodule. Laboratory tests measure the overall function of the thyroid gland to determine if it is hyper (too high) or hypo (too low) active. A thyroid ultrasound can help identify the size and location of the nodule as well as whether it is solid or filled with fluid (cystic).
The fine-needle aspiration is a procedure where a small needle is inserted into the nodule and some of the cells from the thyroid nodule are pulled back into a syringe to be evaluated under the microscope by a pathologist. This test is sometimes performed in the office, if the nodule can be easily felt, but in many cases it is done under ultrasound guidance by a radiologist.
Usually the fine-needle aspiration is performed only for solid nodules over 1 cm in diameter or nodules over 1 cm in diameter that contain both a solid and cystic (fluid filled component). While the fine-needle aspiration biopsy is a great tool, it is not perfect. Because it samples only a small amount of thyroid tissue, sometimes the results are indeterminate which means the pathologist is not quite sure whether the nodule is benign or malignant (cancer) and the test may then need to be repeated.
Benign Thyroid Nodules
If the nodule is found to be benign by FNA, then in most cases the patient only needs to be observed over time either with regularly scheduled physical examinations or ultrasound exams. If the nodule enlarges, the FNA may be repeated or possibly surgery may be advised if it is increasing rapidly in size.
Malignant Thyroid Nodules
If the diagnosis of a malignant thyroid nodule is obtained, then the patient would typically be advised to undergo removal of the entire thyroid gland, possibly along with removal of some of the lymph nodes in the area of the front of the neck. Future treatment may also be needed depending on the type of thyroid cancer. Patients with a family history of thyroid cancer or a personal history of radiation exposure have a higher chance of having malignant thyroid nodules. Worrisome signs and symptoms include rapid increase in size, hoarseness, compression of the esophagus causing dysphagia (problems swallowing) or compression of the trachea causing breathing problems.
If thyroid surgery is indicated, what should I expect?
If thyroid surgery is indicated, there are risks involved. As with any type of surgery bleeding and infection are always a possibility, but the likelihood of a serious complication from either is very low in the hands of an experienced surgeon. The particular risks of thyroid surgery are injury to the surrounding structures. There are two nerves called the recurrent laryngeal nerves that control the movement of the vocal cords. These nerves lie just beneath the thyroid gland capsule and must be clearly identified and preserved during the surgery. Occasionally there may be some temporary hoarseness after surgery due to the manipulation of these nerves during removal of the thyroid gland, but the frequency of permanent hoarseness should be extremely low.
Another important surrounding structure is the parathyroid glands which are located near the thyroid gland, and could also potentially be injured during the surgery. The parathyroid glands control the body’s calcium levels in the blood. Sometimes these glands become temporarily shocked by the surgical procedure which results in a temporary drop in blood calcium levels. The patient may require some temporary calcium supplements during this time as the parathyroid glands recover.
Post Surgery Expectations
Depending on the health of the patient and the amount of surgery required, some thyroid surgery can be done on an outpatient basis, though the patient may need to have blood tests done and a small rubber drain in placed in the neck for the first few days after surgery. Recovery time can typically be 1-2 weeks of light activity and there will be an the patient would expect to have incision in the lower neck that will continue to heal and become a thin relatively unnoticeable scar over the course of 6 to 12 months and typically will be well camouflaged in a natural skin crease.