A thyroidectomy is the total or partial removal of the thyroid gland. This surgical procedure may be performed to remove all or part of a goiter, which is an enlargement of the thyroid gland. This is especially necessary if the enlargement interferes with respiratory function or swallowing. In addition, thyroidectomy may be used to trat increased thyroid function (hyperthyroidism).

Thyroidectomy also may be used to remove thyroid nodules or cancerous and noncancerous thyroid tumors. It is a common form of treatment in patients who have been diagnosed with thyroid cancer.

Located in the lower part of the thyroid cartilage in the front section of the neck, the thyroid gland is part of the endocrine system, a network of glands that produce and secrete hormones. The thyroid gland is shaped like a butterfly, with two lobes, one on the right side and one on the left side – connected in the center by the thyroid isthmus.

The gland is responsible for absorbing iodine from an individual’s blood and using the iodine to produce thyroid hormones. Thyroid hormones play a major role in regulating the body’s metabolism, the body’s process of using food for energy and growth.

The amount of the thyroid gland removed depends on the reason for the surgery. When cancer has been diagnosed, surgery is typically used to remove as much of the tumor as possible. A thyroidectomy is the most effective way to keep thyroid cancer from spreading further and to prevent it from returning. Thyroidectomies are commonly used to treat cases of two types of thyroid cancer: papillary carcinoma and follicular carcinoma. Options for surgery include:

• Total thyroidectomy. Removes the entire thyroid. It may be recommended in cases where the tumor is located in both lobes of the thyroid gland (multifocal) or when the cancer is aggressive.
  
  
• Near-total thyroidectomy. Leaves a small part of the thyroid intact. The advantage of this procedure is that it leaves small rims of tissue around the parathyroid glands (small glands near the thyroid that help regulate calcium levels), reducing the risk of damage to these glands during surgery. In some cases, professionals distinguish between subtotal thyroidectomy (leaving a small amount of thyroid tissue on each side) and near-total thyroidectomy (leaving a small amount of thyroid tissue on one side).

In addition to near-total or total thyroidectomy, there are other forms of surgery that are sometimes used to treat thyroid cancer. These include:

• Lobectomy. Removes only the side of the thyroid where the cancer is located. It generally is used to treat papillary cancers smaller than a half-inch (1 centimeter) that have not spread beyond the thyroid gland. This procedure is common in cases of thyroid cancer known as medullary thyroid carcinoma and anaplastic carcinoma.
  
  
• Lymph node dissection. Removes lymph nodes in the neck near the thyroid. This procedure is called a central compartment neck dissection and is performed when cancer has spread beyond the thyroid into the lymph nodes. It is often performed when a patient’s tumor is bigger than a half-inch (1.5 centimeters).

In some cases, an endoscopic thyroidectomy may be used instead of more invasive surgery. This procedure uses several small incisions in the neck and special instruments to remove small cysts or benign nodules. However, endoscopic thyroidectomy is not used to treat multiple nodules or thyroid cancer.

Other thyroid cancer treatments that may be used in addition to surgery to reduce the risk of cancer recurrence or to treat metastasized cancer include:

• Radioactive iodine therapy. Used to destroy the remaining thyroid gland tissue after surgery and treat any undetected microscopic cancer remaining in the body.
  
  
• Hormone therapy. Many patients experience hypothyroidism (low levels of thyroid hormones) after surgery and treatment with thyroid hormones helps to replace their loss. Doses are typically high to prevent any recurrence of thyroid cancer cells.
  
  
• Radiation therapy.
  
  
• Chemotherapy.