Cause

Experts don't know what causes thyroid cancer. Like other cancers, changes in the DNA of your cells seem to play a role. These DNA changes may include changes that are inherited as well as those that happen as you get older.

One rare type of thyroid cancer, which is called medullary thyroid cancer (MTC), runs in families. You can inherit a specific gene that increases your risk for MTC.

Symptoms

Thyroid cancer can cause many symptoms, including:

• A lump or swelling in your neck. This is the most common symptom.
• Pain in your neck and sometimes in your ears.
• Difficulty swallowing.
• Difficulty breathing or constant wheezing.
• Hoarseness that is not related to a cold.
• A cough that continues and 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.

What Happens

Thyroid cancer is a disease that occurs when abnormal cells begin to grow in the thyroid gland. You may notice a lump in your neck and then go to your doctor. Or your doctor may notice a lump during a routine physical exam or on an imaging test that you are having for another health problem.

Thyroid cancer is usually found before the cancer has spread very far. This means that most people who are treated for thyroid cancer do very well. After it is treated, thyroid cancer may come back, sometimes many years after treatment.

Before starting your treatment, your doctor needs to find out which type of thyroid cancer you have. A biopsy can identify your type of cancer. During a biopsy, a small piece of thyroid tissue is removed, usually with a fine needle. The thyroid tissue cells are then examined under a microscope.

It is also important to find out the stage of your cancer. Staging is a way for your doctor to tell how far, if at all, the cancer has spread. It also helps your doctor decide what kind of treatment you need. Staging generally depends on the results of your radioactive iodine scan.

If you have your thyroid gland surgically removed, you will probably need to take thyroid hormone medicine for the rest of your life to replace the hormones that were made by your thyroid. Taking it will help regulate your metabolism and other body functions.