What is thyroid cancer?

Thyroid cancer is a disease that you get when abnormal cells begin to grow in your thyroid gland. The thyroid gland is shaped like a butterfly and is located in the front of your neck. It makes hormones that regulate the way your body uses energy and that help your body work normally.

Thyroid cancer is an uncommon type of cancer. Most people who have it do very well, because the cancer is usually found early and the treatments work well. After it is treated, thyroid cancer may come back, sometimes many years after treatment.

What causes thyroid cancer?

Experts do not know the exact cause of thyroid cancer. But they do know that people who have been exposed to a lot of radiation-either from the environment or from medical treatment-have a greater chance of getting thyroid cancer.

A dental X-ray now and then will not increase your chance of getting thyroid cancer. But past radiation treatment of your head, neck, or chest (especially during childhood) can put you at risk of getting thyroid cancer. Radiation was used from the 1920s to the 1950s to treat problems such as acne or enlarged tonsils, but it is no longer used to treat health problems other than cancer.

What are the symptoms?

Thyroid cancer can cause several symptoms:

• You may get a lump or swelling in your neck. This is the most common symptom.
• You may have pain in your neck and sometimes in your ears.
• You may have trouble swallowing.
• You may have trouble breathing or have constant wheezing.
• Your voice may be hoarse.
• You may have a frequent cough that is not related to a cold.

Some people may not have any symptoms. Their doctors may find a lump or nodule in the neck during a routine physical exam.

How is thyroid cancer diagnosed?

If you have a lump in your neck that could be thyroid cancer, your doctor may do a biopsy of your thyroid gland to check for cancer cells. A biopsy is a simple procedure in which a small piece of the thyroid tissue is removed, usually with a needle, and then checked.

Sometimes the results of a biopsy are not clear. In this case, you may need surgery to remove all or part of your thyroid gland before you find out if you have thyroid cancer.

How is it treated?

Thyroid cancer is treated with surgery and radioactive iodine treatment. It rarely needs radiation therapy and chemotherapy. What treatment you need depends on your age, the type of thyroid cancer you have, and the stage of your disease. Stage refers to how severe the disease is and how far, if at all, the cancer has spread.