About 70-75% of all thyroid cancers diagnosed in the United States are papillary carcinoma. It is more common in females than in males.

The cause of this cancer is unknown. However, mutations that effect cell growth in the thyroid may play a role.

Exposure to external radiation to the neck increases the risk of developing thyroid cancer. The risk for developing thyroid cancer continues for approximately twenty years after the thyroid is exposed to high-doses of radiation. Intravenous exposure to radiation for medical tests and treatments, however, does not increase the risk of developing thyroid cancer.

Thyroid cancer usually presents as a nodule in the thyroid gland. The diagnosis is made by fine needle aspiration. However, it should be emphasized that most thyroid nodules (90%) are benign.

A thyroid nodule should be evaluated by blood work and a thyroid ultrasound. Any nodule which is greater that 1.0 cm on ultrasound should be further evaluated with fine needle aspiration (FNA).

FNA is used to determine if a nodule in the thyroid gland is cancerous or benign. A needle is inserted into the nodule, and a small amount of tissue is taken into the needle. The procedure can be done in the office or with ultrasound guidance.

Thyroid function tests are usually normal in patients with thyroid cancer.

There are 3 parts to the treatment of thyroid cancer -- surgery, radioactive iodine, and medication. The hospitals best equipped to treat thyroid cancer are the large academic centers.

The surgeons and endocrinologists see many patients with thyroid cancer and are experts in operating and treating this cancer. They are also up to date on the latest developments for treatment of cancer.

• Surgery should be performed to remove as much of the tumor as possible. The size of the tumor will dictate how much of the thyroid gland is removed. Frequently, the entire thyroid gland is removed.
• After the surgery, most (but not all) patients are treated with radioactive iodine, which targets any leftover thyroid tissue and destroys it. This also helps in imaging to look for additional cancer.
• If surgery is not an option, external radiation therapy can be useful.
• If the cancer has spread to other parts of the body, it can be treated with surgery to alleviate compression on bones or nerves by large tumors.
• After surgery, the patient will need to take thyroid hormone for life. This medication is called levothyroxine sodium.

Routine follow-up after curative treatment involves blood tests every 3 to 6 months, and a radioactive iodine (I-131) scan at 9 to 12 months and then yearly.

Ten-year prognosis for papillary cancer of the thyroid is good. About 95% of adults with this cancer survive 10 years. The prognosis is better for patients younger than 40 years of age and for patients with smaller tumors. Soft tissue invasion, large tumors, older patients, and the presence of distant metastases are poor prognostic signs.

• After the thyroid gland has been removed, replacement of thyroid hormone with a drug called levothyroxine is required. One must take this for life. Other complications include accidental removal of the parathyroid glands (a gland involved in regulating calcium levels), and damage to a nerve that controls the vocal cords.
• Rarely, spreading of cancer to lymph nodes or through blood vessels to other sites (metastasis) occurs.

Call for an appointment with your health care provider if symptoms of this disorder occur.

Call for an appointment with your health care provider if you have had a thyroidectomy and new symptoms develop, including muscle twitching, cramps, or changes in your voice.