Thyroid and Parathyroid Disorders
The thyroid gland, located at the base of your neck, produces hormones that regulate metabolism, heart rate and body temperature. Every cell in your body depends on the thyroid hormones. The thyroid gland is prone to many very distinct problems, some of which are very common. These problems include:
- Hyperthyroidism: overproduction of thyroid hormone
- Hypothyroidism: underproduction of thyroid hormone
- Benign goiter: enlarged thyroid
- Thyroid nodules (benign and cancerous)
Goiter is often caused by a diet deficient in iodine and is not common in the United States of America. When goiter does occur among Americans, a more common cause is an increase in thyroid stimulating hormone (TSH) that is a result of hypothyroidism. This condition may be medically managed by providing thyroid hormone in the form of a pill.
If the goiter continues to grow, patients may be referred for surgery, especially if it begins to compress on other structures in the neck, such as the trachea and esophagus. The suspicion of malignancy is also cause to surgically remove the thyroid. It should be noted, however, that the incidence of malignancy within a multi-nodular goiter is very small.
Nodules, which can often be felt as a lump in the neck, may occur within the thyroid gland. More than 90 percent of all thyroid nodules are benign (non-cancerous) growths.
Risk factors for thyroid cancer include exposure to radiation (including previous treatment for head and neck cancers), personal or family history of goiter (enlarged thyroid) and certain inherited genetic syndromes. In addition to a lump in the neck, symptoms may include changes to the voice, difficulty swallowing, and a pain in the neck and throat. Patients may also have swollen lymph nodes in the neck.
Physicians diagnose thyroid cancer in a number of ways, including a physical exam, blood tests to measure levels of thyroid stimulating hormone, a fine needle biopsy to examine cells in the thyroid and imaging tests such as a thyroid ultrasound.
A multi-disciplinary team made up of thyroid surgeons, endocrinologists, radiologists, and nuclear medicine physicians convene to provide comprehensive thyroid cancer care. Highly skilled surgeons at GW Hospital remove the cancer while preserving a patient’s laryngeal nerves and parathyroid glands.
One of these surgeries available for some patients who have thyroid nodules is a minimally invasive, video-assisted thyroidectomy. In this procedure, surgeons use an endoscope to remove all or part of the thyroid. By using an endoscope and other special instruments, surgeons can make smaller incisions. Some patients may also have radioactive iodine treatments (or internal radiotherapy) after their surgery.
Parathyroid glands are four small glands in the neck that make a hormone that helps regulate the level of calcium in the body. Disorders of the parathyroid include:
- Hyperparathyroidism: overactivity by one or more of the parathyroid glands
- Parathyroid Tumors
Hyperparathyroidism is a common disease of the parathyroid gland caused by overactivity of one or more of the parathyroid glands. As a result, the glands make too much of the parathyroid hormone and can cause a serious calcium imbalance. Hyperparathyroidism can be caused by tumors that elevate the level of parathyroid hormone, which then causes a rise in the level of Ca2+ (calmodulin-dependent protein kinase) in the blood, at the expense of calcium stores in the bones. Over time, patients may develop osteopenia, in which the bones become brittle and there is an increased risk of fracture.
Treatment for hyperparathyroidism involves the removal of the abnormal gland or glands. In about 90 percent of cases, only one of the four glands has been affected by a benign tumor and that gland is the only one that is hypersecreting. This condition is called parathyroid adenoma.
In only about 10 percent or fewer cases, patients with hyperparathyroidism have had all four glands grow large (hyperplasia) and secrete too much parathyroid hormone (PTH). This condition is called parathyroid hyperplasia.
A parathyroid adenoma is a noncancerous (benign) tumor found in the parathyroid glands, and can be caused by a genetic problem. The most common cause of parathyroid adenoma is hyperparathyroidism, which leads to increased blood calcium levels.
There is a rare cancer that sometimes forms in tissues of one or more parathyroid glands. That cancer can be treated with surgery and/or radiation therapy. Surgeons at GW Hospital offer minimally invasive parathyroidectomy, with and without video assistance. In the video-assisted surgery, physicians use targeted incisions and endoscopes to provide more precise localization of parathyroid tumors and remove the affected gland.
When patients have hyperplasia, in which all four glands are enlarged, all hypersecreting glands are typically removed surgically. Then, part of one gland is either re-implanted in a muscle in neck or forearm, or part of one gland is left in place if it is not enlarged.