Thyroid nodules are abnormal “growths” within the substance of the thyroid gland. They are very common – occurring in about 10% of people in the United States. Most individuals with thyroid nodules are not even aware that the nodules are present. However, some people are able to feel nodules in their thyroid on self-examination, while others are diagnosed during physical examination by a physician. Sometimes thyroid nodules are found incidentally during a study such as a CT scan, PET scan, or even a chest x-ray. Once found, they require additional work-up to make sure there is no sign of malignancy.
Initial testing of thyroid nodules will usually involve laboratory tests of the blood (TSH level, T4 level, T3 level) and an ultrasound examination of the neck. The lab tests, called thyroid function tests, will tell the physician how well the thyroid gland is functioning – within the normal range (euthyroid), underactive (hypothyroid), or overactive (hyperthyroid). The ultrasound examination is the most revealing exam for the thyroid gland. It will tell the physician the size of the nodule, whether it is cystic (fluid filled) or solid, and whether there are multiple nodules present. It will also give the physician information about the character of the nodule – shape, calcifications, and blood flow pattern. Ultrasound can also detect surrounding lymph nodes and determine whether they are enlarged or not.
Thyroid nodules which are larger than 15 mm in size and are primarily solid, or any nodule with worrisome features, will need to be biopsied. This is a straightforward procedure usually performed by a radiologist with ultrasound guidance. A fine needle, smaller than the needle used to draw blood, is employed. While visualizing the needle and nodule in the ultrasound image, the tip of the needle is advanced through the skin and into the thyroid nodule. Several dozen cells are aspirated (sucked up) into the needle and placed on a microscope slide for analysis by a pathologist skilled in this type of study. The procedure is done while the patient is awake, with local anesthesia, and the patient may drive themselves home after the procedure.
The results of a fine needle aspiration (FNA) biopsy will usually fall into one of three categories – benign, malignant, or indeterminant due to atypia. These results with help guide treatment, and assist your surgeon in deciding whether or not an operation is required, and if so, what type of surgical procedure would be best in this particular case. Most nodules undergoing FNA biopsy turn out to be benign (75%). A relatively small number are definitely malignant when examined by the pathologist (5%). In about 20% of cases, the results are indeterminant and a decision will need to be made with your surgeon as to whether the nodule should be removed, or if it can be safely monitored.
At times, other studies may be needed to further evaluate nodules in the thyroid. These may include laboratory tests for thyroid antibodies, nuclear thyroid scans, CT scans of the neck and chest, and even MRI scans. Your physician will help determine whether any of these additional studies are necessary in further evaluating a thyroid nodule.
Our thyroid patients come to us from Winston-Salem, Burlington, High Point, Greensboro, Kernersville and adjacent communities.