What are thyroid tumors?
The thyroid gland is located in the front of the neck at the base
of the throat. Thyroid tumors are either benign (noncancerous) or
malignant (cancerous) growths. Examples of benign tumors are adenomas,
which may secrete thyroid hormone. Malignant tumors are more rare and
are more common in women than in men. According to the American Cancer
Society (ACS), over 56,000 cases of thyroid cancer are expected to be
diagnosed in the U.S. in 2012.
What are thyroid adenomas?
Thyroid adenomas are small growths (nodules) that start in the cell
layer that lines the inner surface of the thyroid gland. The adenoma
itself may secrete thyroid hormone. If the adenoma secretes enough
thyroid hormone, it may cause hyperthyroidism. Thyroid adenomas may be
treated if they cause hyperthyroidism. Treatment may include surgery to
remove part of the thyroid (the overactive nodule).
What are cancerous thyroid tumors?
Cancer of the thyroid occurs more often in people who have
undergone radiation to the head, neck, or chest. However, it may occur
in people without any known risk factors. Most thyroid cancer can be
cured with appropriate treatment. Thyroid cancer usually appears as
nodules within the thyroid gland. Some signs that a nodule may be
Presence of a single nodule rather than multiple nodules
Thyroid scan reveals the nodule is not functioning
Nodule is solid instead of filled with fluid (cyst)
Nodule is hard
Nodule grows fast
What are the symptoms of thyroid cancer?
The first sign of a cancerous nodule in the thyroid gland is usually a painless lump in the neck.
Other symptoms may include:
Hoarseness or loss of voice as the cancer presses on the nerves to the voice box
Difficulty swallowing as the cancer presses on the throat
Throat or neck pain that does not go away
A cough that does not go away
However, the symptoms of thyroid cancer may resemble other
conditions or medical problems. Always consult your doctor for a
How is thyroid cancer diagnosed?
In addition to a complete medical history and medical examination, diagnostic procedures for thyroid cancer may include:
Are there different forms of thyroid cancer?
There are four main forms of thyroid cancer:
Papillary thyroid cancer
Papillary thyroid cancer is the most common form of thyroid
cancer, accounting for about 80 percent of all cases. This form of
thyroid cancer affects more women than men.
Treatment for papillary cancer may include:
Surgery. This is done to remove part or all of the thyroid (called a thyroidectomy) and sometimes nearby lymph nodes
Thyroid hormone therapy. This is done to suppress
the pituitary gland from secreting more thyroid-stimulating hormone,
which may stimulate a recurrence of papillary cancer.
Administration of radioactive iodine. This is done to destroy any remaining thyroid tissue.
Follicular thyroid cancer
Follicular thyroid cancer accounts for about 10 percent of
thyroid cancer cases. This type of thyroid cancer is more aggressive and
tends to spread through the bloodstream to other parts of the body.
Still, the prognosis (outlook) is very good in most cases.
Treatment for follicular cancer may include:
Anaplastic thyroid cancer
Anaplastic thyroid cancer tends to occur most often
among women and accounts for about 2 percent of thyroid cancer cases.
This quick-growing cancer usually results in a large growth in the
neck. It has often spread to other parts of the body by the time it is
found and is very hard to treat effectively.
Treatment for anaplastic thyroid cancer may include:
Surgery. This is done to remove the thyroid gland (thyroidectomy) if it has not spread extensively, although this is rare.
Chemotherapy (for example, anti-cancer drugs)
Medullary thyroid cancer
Medullary thyroid cancer accounts for about 4 percent of
thyroid cancers. It tends to spread through the lymphatic system (which
consists of a system of vessels that connect lymph nodes throughout the
body) and the bloodstream to other parts of the body. This type of
cancer produces excessive amounts of calcitonin, a hormone also produced
by the thyroid gland itself.
Treatment for medullary thyroid cancer may include:
Surgery. This is done to remove the thyroid gland (thyroidectomy) and sometimes nearby lymph nodes.
Targeted therapy drugs, such as vandetanib
Additional surgery or other treatments may be necessary if the cancer has spread.
Because medullary cancer tends to run in families, screening
tests for genetic abnormalities in the blood cells may be conducted.