Thyroid Cancer

What is Thyroid CancerThyroid cancer occurs in the cells of the thyroid — a butterfly-shaped gland located at the base of your neck, just below your Adam's apple. Your thyroid produces hormones that regulate your heart rate, blood pressure, body temperature and weight.

Thyroid cancer isn't common in the United States. About 37,000 people are diagnosed with thyroid cancer each year, according to the National Cancer Institute. Thyroid cancer rates seem to be increasing, which doctors think may be due to new technology that allows them to find small thyroid cancers that may not have been found previously.

Symptoms
Thyroid cancer typically doesn't cause any signs or symptoms early in the disease. As thyroid cancer grows, it may cause:

A lump that can be felt through the skin on your neck
Changes to your voice, including increasing hoarseness
Difficulty swallowing
Pain in your neck and throat
Swollen lymph nodes in your neck
When to see a doctor
If you experience any signs or symptoms that worry you, make an appointment with your doctor. Thyroid cancer isn't common, so your doctor may investigate other causes of your signs and symptoms first.

Cause
It's not clear what causes thyroid cancer. Thyroid cancer occurs when cells in your thyroid undergo genetic changes (mutations). The mutations allow the cells to grow and multiply rapidly. The cells also lose the ability to die, as normal cells would. The accumulating abnormal thyroid cells form a tumor. The abnormal cells can invade nearby tissue and can spread throughout the body.

Types of Thyroid Cancer
Papillary thyroid cancer. The papillary type of thyroid cancer is the most common, making up about 80 percent of all thyroid cancer diagnoses. Papillary thyroid cancer can occur at any age, but is most commonly diagnosed in people ages 30 to 50.
Follicular thyroid cancer. Follicular thyroid cancer also includes Hurthle cell cancer. Follicular thyroid cancer typically occurs in people older than 50.
Medullary thyroid cancer. Medullary thyroid cancer may be associated with inherited genetic syndromes that include tumors in other glands. Most medullary thyroid cancers are sporadic, meaning they aren't associated with inherited genetic syndromes.
Anaplastic thyroid cancer. The anaplastic type of thyroid cancer is very rare, aggressive and very difficult to treat. Anaplastic thyroid cancer typically occurs in people age 60 or older.
Thyroid lymphoma. Thyroid lymphoma begins in the immune system cells in the thyroid. Thyroid lymphoma is very rare. It occurs most often in adults age 70 or older.