The thyroid is a butterfly-shaped gland located at the base of the front of the neck. It produces thyroid hormone, which controls your metabolism, temperature regulation, and keeps your muscles and organs working properly. Thyroid cancer is very common, particularly in women. It is now one of the most common cancers found in women. Most forms of thyroid cancer are slow-growing and well-treated with surgery and sometimes other therapies.
Thyroid cancers are often found within nodules that are either felt by the patient or their doctor. These nodules are also frequently found incidentally, for example, when the patient has an imaging test not related to the thyroid.
Many patients with thyroid cancer do not report any symptoms, though the following symptoms may be present:
There are several types of thyroid cancer including:
Papillary—This is the most common form of thyroid cancer. This type of cancer, which tends to grow slowly, has a good prognosis. It often spreads to neck lymph nodes.
Follicular—This type of thyroid cancer also typically has a good overall prognosis except when significant invasion of other tissues is present.
Medullary—This form of thyroid cancer develops from cells in the thyroid gland that are different from papillary and follicular thyroid cancers. While the prognosis with medullary cancer is not as favorable when compared with those types of thyroid cancers, it is also much less common (between five- and 10-percent of all thyroid cancers). While medullary thyroid carcinoma can be associated with several inherited syndromes, more often it occurs in patients without any family history.
Anaplastic—This is the least common type of thyroid cancer, but it is very aggressive, and the prognosis is poor. It presents as a rapidly enlarging neck mass.
A biopsy with a needle (called fine needle aspiration or FNA) may be performed based on physical exam and ultrasound, or radiographic findings. In some patients, a biopsy may show a cancer, and surgery will be recommended. In others, biopsies may be indeterminate, and a cancer diagnosis is confirmed only after surgical removal. At times, a genetic analysis may be added to the biopsy, to help further clarify the risk of cancer and guide treatment decision-making.
The primary treatment for thyroid cancer is surgery. This surgery involves removing the thyroid gland and sometimes enlarged lymph nodes. Surgical treatment is determined on a case-by-case basis and is determined by the patient’s biopsy and imaging, as well as other factors. Treatment options include:
Papillary—This type of cancer is treated with thyroid surgery and, in selected cases, radioactive iodine.
Follicular—This type of thyroid cancer is treated similarly to papillary carcinoma, with thyroid surgery and, in selected cases, radioactive iodine.
Medullary—Treatment for medullary thyroid cancer is primarily surgical. If the cancer is found to be inherited then family members of the patient may need genetic screening testing.
Anaplastic—This cancer often grows very quickly and requires a medical team comprised of several specialists to determine the best treatment plan.
Copyright 2021. American Academy of Otolaryngology–Head and Neck Surgery Foundation. Last reviewed April 2020.