The thyroid is a butterfly-shaped gland that is located in the lower neck and rests in front of the trachea (windpipe). One of the largest endocrine organs in the body, the thyroid produces hormones that help regulate growth and metabolism (how the body processes energy). Diseases of the thyroid gland typically include abnormalities in the production of thyroid hormone (either too much or too little hormone), or abnormalities in the anatomy or structure of the thyroid (such as a thyroid nodule).
Hypothyroid and Hyperthyroid
The most common functional abnormality of the thyroid gland is hypothyroidism. This occurs when the thyroid gland makes too little thyroid hormone. Common symptoms of hypothyroidism may include fatigue, unexplained weight gain, intolerance of cold, constipation, dry skin, brittle hair, joint and muscle pains, or difficulty with concentration.
A less common abnormality of the thyroid gland is hyperthyroidism. This occurs when the thyroid gland makes too much thyroid hormone. Common symptoms of hyperthyroidism may include racing heart, hand tremor, intolerance of heat, unexplained weight loss, anxiety, or insomnia. There are many different reasons why the thyroid gland might make too much or too little thyroid hormone.
Often, the thyroid gland functions normally, but there might be a structural or anatomical abnormality such as a thyroid nodule. These nodules are lumps that arise in an otherwise normal thyroid gland. Thyroid nodules are typically discovered by a physician during a routine office visit, or by imaging scans (ultrasound, CT scan, MRI) performed for other health reasons.
Thyroid nodules are very common, and are seen in up to 60 percent of women over the age of 50 years. The vast majority of thyroid nodules are noncancerous. In a small percentage of patients, the nodule may be cancerous. Thyroid cancer is uncommon and is typically a very treatable form of cancer, particularly when diagnosed early.
Some benign thyroid nodules make excessive amounts of thyroid hormone, and are referred to as “toxic nodules.” These nodules are almost never cancerous, but they can cause symptoms of hyperthyroidism and need to be treated. In addition to surgery, we offer radiofrequency ablation (RFA) as a treatment option.
An enlarged thyroid gland is called a goiter. Thyroid nodules are often present in enlarged thyroid glands, a condition referred to as a multinodular goiter. Goiters can sometimes cause pressure on other structures within the neck, including the esophagus and trachea. When severe, this can cause difficulty with swallowing and breathing. For some patients, the presence of a goiter can also be less desirable for cosmetic reasons. For all of the above reasons, surgery can be recommended.
Thyroid Disorder Diagnosis
There are a number of tests used to detect thyroid disease.
- Thyroid function testing is a blood test to determine the level of thyroid hormones TSH (thyroid stimulating hormone), T4 (thyroxine) and T3 (triiodothyronine). The levels of thyroglobulin and calcitonin (markers for thyroid cancer) and antibodies associated with autoimmune diseases may also be determined.
- Thyroid ultrasound imaging involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body. The sound waves are emitted from a small hand-held transducer that is passed over the thyroid. Ultrasound images show the structure and movement of the internal organs in real time. An ultrasound exam of the thyroid is typically done to help diagnose a lump in the thyroid or a thyroid that is not functioning properly. Ultrasound can also be used to assess lymph nodes in the neck in cases of suspected thyroid cancer. The use of thyroid ultrasound facilitates an immediate answer regarding the size and characteristics of a thyroid nodule, and allows the endocrinologist to determine the need for a biopsy.
- Ultrasound-guided fine needle aspiration biopsy is a method of removing a small tissue sample from a nodule using a thin, hollow needle. The placement of the needle is guided with ultrasound imaging. The tissue sample is examined in a laboratory to determine if the cells are benign or malignant (cancerous). For patients with a positive biopsy or suspicious cells, an appointment with a surgeon is arranged.
- Thyroid uptake/scan is a nuclear medicine test that uses a radioactive iodine tracer to see how well the thyroid is working. A patient is given a pill that contains radioactive iodine. After the radioactive iodine has been absorbed by the thyroid (in a few hours), the scanner detects the location and intensity of the rays given off by the radioactive material. A computer displays images of the thyroid gland. This test is done to check for hyperthyroidism, thyroid cancer and thyroid nodules or other growths.
- CT and MRI may be used to capture images of thyroid abnormalities and diagnose thyroid disease.
- Thyrogen stimulation is a synthetic form of thyroid stimulating hormone (TSH) given to patients to assist in the diagnosis and treatment of thyroid cancer.
Thyroid Disease Research
Our physicians and scientists continually search for new ways to diagnose and treat a wide range of diseases and disorders. In thyroid disease, current research involves:
- Looking at molecular pathways that lead to the development of thyroid cancer
- Investigating diagnostic strategies for thyroid cancer
- Conducting clinical drug trials for thyroid cancer