Thyroid Cancer/Thyroid Carcinoma

The thyroid gland is located in the lower front of the neck, below the voice box (larynx) located in the upper part of the neck, and above the collarbones. Thyroid cancer (carcinoma) usually appears as a painless lump in this area. In most cases, the lump affects only one side, and the results of thyroid function tests (blood tests) are usually normal.

Over 35,000 new cases of thyroid cancer are expected in the United States every year. Women are 2 to 3 times more likely to have thyroid cancer than men. Thyroid cancer is most common after 30, but it can develop at any age.

There are four types of thyroid cancer tumors:

Papillary Tumors

They account for about 80 percent of thyroid cancers.
Papillary tumors develop more often during 30-60 years of age.
They occur three times more often in women than in men.
The cure rate is usually 97 percent or better.
Papillary tumors often spread to lymph glands in the neck (metastasis), but rarely spread to distant organs.
The lungs, liver and bones are typically the most common sites of distant metastasis.

Follicular Tumors

The second most common thyroid cancer.
Metastasis to distant organs, (lungs, bones, brain, liver, bladder, skin) is more common than with papillary carcinoma.
Metastasis to the lymph glands is less common than in papillary tumors.
Follicular tumors usually develop during 40-60 years of age.
They occur three times more often in women than men.
The cure rate is typically 90 percent or better.

Medullary Tumors

Metastasis to the lymph nodes occurs in the early stage of the tumor.
After surgery, the hormone calcitonin is measured every four to six months to check for recurrence of the disease.
The survival rate is 90 percent if the disease has not spread outside of the thyroid gland. Survival is 70 percent if disease has spread to lymph glands in the neck, and 20 percent if the disease has spread to distant organs.

Anaplastic Tumors

The least common type of thyroid cancer, but the most dangerous.
Three years after diagnosis and treatment, only 10 percent of patients are alive.
More than 90 percent of anaplastic cancers spread to the lymph glands in the neck and distant organs.
The tumors grow rapidly.
The average age of onset is 65 years of age and older.
Men are two times more likely than women to have anaplastic cancer.
Many patients require a tracheostomy (breathing tube placed into the neck) because the tumor presses against the trachea and inhibits breathing.
This cancer must be detected early.
The cure rate is very low.

Symptoms

Many patients with thyroid cancer have no symptoms whatsoever, and are found by chance to have a lump in the thyroid gland on a routine physical exam or an imaging study of the neck done for unrelated reasons (CT or MRI of spine or chest, carotid ultrasound, etc). Some patients with thyroid cancer become aware of a gradually enlarging lump in the front portion of the neck, which usually moves with swallowing. Occasionally, the lump may cause a feeling of pressure. Obviously, finding a lump in the neck should be brought to the attention of your physician, even in the absence of symptoms.

Causes and Risk Factors

The exact reason nodules grow in the thyroid gland is not known. But these factors increase the risk:

Heredity. If a parent or sibling had a thyroid nodule, the chance of developing a nodule is increased.
Age. The risk of developing a nodule increases as you age.
Gender. Woman develop nodules more often than men
Thyroiditis. Nodules are more likely to form in people who have chronic inflammation of the thyroid gland.
Radiation exposure to the head or neck. Babies, children, and teenagers were treated with radiation for birthmarks, acne or enlarged tonsils in the 1940s and 1950s. People who had these treatments have an increased risk. Exposure to nuclear power plant accidents, or radioactive particles released into the air during atomic weapons testing also increases the risk.

Diagnosis

A combination of symptoms, medical history, physical exams, and tests are used to determine a diagnosis. Thyroid nodules are often found during a routine physical examination. Your doctor might feel an abnormal lump on the front of your neck.

The TSH blood test measures a pituitary gland hormone that stimulates the thyroid gland. If the TSH level is increased, the thyroid gland may not be functioning properly. Additional blood tests are needed to measure other thyroid hormones. Both pituitary and thyroid tests are required to confirm that the problem is located in the thyroid gland.
T4 by RIA and T3 by RIA are blood tests also used to measure thyroid function.
A thyroid scan measures the amount of iodine the thyroid can absorb.
Fine Needle Aspiration Biopsy (FNA). A needle is placed into the thyroid nodule, the cells are aspirated, and then examined under a microscope to determine if a nodule is cancerous.
Thyroid ultrasound uses painless sound waves to create an image of the thyroid gland and identify nodules. Ultrasound can show if a nodule is solid or a fluid-filled cyst, but it cannot determine if a nodule is benign or malignant.

Treatments

Thyroid tumors require surgical removal of part or all of the thyroid gland (thyroidectomy). The surgeons in the Thyroid Cancer Center are experts in the treatment of thyroid tumors.

Radioactive iodine treatments are given to many patients with thyroid cancer after the tumor is removed.