Treatment

The treatment of thyroid cancer depends on the size and location of the tumor, the type of thyroid cancer, whether the cancer has spread, and the person’s overall health. In many cases, a team of doctors will work with the patient to determine the best treatment plan, including a surgeon, endocrinologist (a doctor specializing in problems with glands and the endocrine system), medical oncologist, and radiation oncologist.

This section outlines treatments that are the standard of care (the best treatments available) for this specific type of cancer. Patients are also encouraged to consider clinical trials as a treatment option when making treatment plan decisions. A clinical trial is a research study to test a new treatment to prove it is safe, effective, and possibly better than standard treatment. Your doctor can help you review all treatment options. For more information, visit the Clinical Trials section.

Cancer treatment is often selected based on guidelines recommended by panels of expert physicians. Although most thyroid cancers are curable, there can be different opinions in how to treat thyroid cancer, particularly in which combination of treatments to use. Patients are encouraged to seek a second opinion before starting treatment because they should be comfortable with the treatment plan they choose and should ask about clinical trials.

Thyroid cancer is treated by one or a combination of treatments, including surgery, radioactive iodine, hormone treatment, external-beam radiation therapy, and/or chemotherapy.

Descriptions of the most common treatment options for thyroid cancer are listed below followed by an outline of common cancer treatments given at which stage of disease.

Surgery

Surgery is the main treatment for most thyroid cancers. A surgical oncologist is a doctor who specializes in treating cancer using surgery. Depending on the size of the nodule, the surgeon will perform a total thyroidectomy (surgery to remove the entire thyroid gland), a near-total thyroidectomy (surgery to remove the thyroid gland except for a small part), or a lobectomy (surgery to remove the lobe with the cancerous nodule). Total or near-total thyroidectomies are the most common operations for thyroid cancer; lobectomies are performed on some patients with papillary or follicular thyroid cancer. If there is evidence or risk of spread of cancer to the lymph nodes in the neck, the surgeon may also perform a neck dissection (surgery to remove the lymph nodes in the neck; also called a lymphadenectomy).

Complications of surgery may include damage to the parathyroid glands (which help regulate blood calcium levels), excessive bleeding, or wound infections. If the nerves to the larynx are damaged during surgery, this may cause temporary or permanent hoarseness or a “breathy” voice. Learn more about cancer surgery.

Without the thyroid gland, the body stops producing thyroid hormone, which is essential to a body’s functioning. Hormone replacement (see below), usually given by a daily pill, is the best solution. The patient may also have to take vitamin D and calcium supplements if the parathyroid gland function is impaired after surgery.

Hormone treatment

Patients who are treated for papillary, follicular, and medullary thyroid cancers by surgery require thyroid hormone therapy. In addition to replacing the hormone that is needed by the body, the thyroid hormone medication will slow down the growth of any remaining differentiated cancer cells, an important double purpose.

Thyroid hormone replacement is levothyroxine (Levothroid, Levoxyl, Synthroid, Unithroid). Levothyroxine typically comes as a pill that should be taken daily, at the same time each day so that the body receives a consistent supply. Thyroid pills have few side effects. Occasionally, some patients develop a rash or lose some hair during the first months of treatment. The doctor will monitor the patient’s thyroid hormone levels through regular blood tests. Hyperthyroidism (too much hormone) may cause weight loss, chest pain, rapid heart rate or arrhythmias (irregular heartbeat), cramps, and diarrhea; patients may also feel hot and sweaty. Hypothyroidism (too little hormone) may cause fatigue, weight gain, and dry skin and hair; patients may also feel cold. The amount of thyroid hormone required is different for every patient and tumor type, and it can change as a person ages.

Radioactive iodine (radioiodine) therapy

The thyroid absorbs almost all iodine that enters a body. Therefore, radioactive iodine (also called I-131 or RAI) is given as a way to find and destroy thyroid cells not removed by surgery and those that have spread beyond the thyroid.

Not all patients require this treatment. Patients with medullary or anaplastic thyroid cancer are not treated with I-131.

I-131 therapy is given in either liquid or pill form. Patients receiving I-131 to kill cancer cells may or may not be hospitalized for two to three days, depending on several factors including the dose given.

Patients are encouraged to drink fluids to help the I-131 pass quickly through the body. Within a few days, most of the radiation is gone. Talk with your doctor about ways to limit radiation exposure to other people, including children, who may be around you during this treatment and the days following it.

In preparation for radioactive iodine treatment after surgery, patients are usually asked to avoid an iodine-rich diet for two to three weeks beforehand. In addition to the low-iodine diet, patients will be asked to either stop taking thyroid hormone replacement pills temporarily or will receive injections of recombinant TSH (Thyrogen) while taking the hormone replacement.

It is important to discuss the possible short-term and long-term effects of I-131 therapy with your doctor. On the first day of treatment, patients may experience nausea and vomiting. In certain circumstances, pain and swelling can occur in the areas where the radioactive iodine is collected. Because iodine is concentrated in salivary gland tissue, patients may experience swelling of the salivary glands; this may result in xerostomia (dry mouth).

Large or cumulative doses of radioactive iodine may cause infertility, especially in men. It is recommended that women avoid pregnancy for at least one year after radioactive iodine treatment. Occasionally, patients may require repeated radioactive treatments over time. However, there is a maximum total dose of radioactive iodine allowed over time, and once reached, this may prevent further use of this treatment.

Epidemiologic studies (studies that determine the cause of cancer in large groups of people) have shown that repeated high-dose radioactive treatment can cause leukemia and occasionally urinary bladder cancer.

External-beam radiation therapy

Radiation uses high-energy x-rays to kill cells. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. The most common type of radiation treatment is called external-beam radiation therapy, which is radiation given from a machine outside the body. Radiation therapy is usually given as outpatient therapy five days a week for about five to six weeks either in a hospital or clinic.

For thyroid cancer, external-beam radiation therapy is used only in certain circumstances, typically when advanced thyroid cancer has not responded to radioiodine therapy. Radiation therapy is usually given after surgery, and treatment is concentrated on a specific area, only affecting cancer cells at that site.

Side effects depend on the treatment dosage and area and may include redness of the skin, odynophagia (painful swallowing), cough, occasional hoarseness, nausea, and fatigue. Most side effects go away soon after treatment is finished.

Chemotherapy

Chemotherapy is the use of drugs to kill cancer cells and is sometimes used to treat thyroid cancer. Systemic chemotherapy is delivered through the bloodstream, targeting cancer cells throughout the body. Chemotherapy is given by a medical oncologist, a doctor who specializes in treating cancer with medication. Some people may receive chemotherapy in their doctor’s office; others may go to the hospital. A chemotherapy regimen (schedule) usually consists of a specific number of cycles given over a specific time. The goal of chemotherapy can be to destroy cancer remaining after surgery, slow the tumor’s growth, or reduce symptoms.

At this time, the use of systemic chemotherapy for the treatment of thyroid cancer is determined on an individual basis and is most often given as part of a clinical trial (research study). With new knowledge in the molecular abnormalities of cancer cells, scientists are developing therapies that specifically target such abnormalities. In turn, the cancer therapy can be more specific. See the Current Research section for more information.

The side effects of chemotherapy depend on the individual and the dose used. The side effects of chemotherapy depend on the individual and the dose used but can include fatigue, risk of infection, nausea and vomiting, loss of appetite, and diarrhea. These side effects usually go away once treatment is finished.

Learn more about chemotherapy and preparing for treatment. The medications used to treat cancer are continually being evaluated. Talking with your doctor is often the best way to learn about the medications prescribed for you, their purpose, and their potential side effects or interactions with other medications. Learn more about your prescriptions by using searchable drug databases.

Treatment options by stage

If the thyroid cancer is only within the tissues of the neck, both in the thyroid gland and in the lymph nodes, surgery will typically be the first treatment. Patients with more advanced disease may be treated with surgery as well, but other treatments may be done first.

Stage I: Surgery; hormone therapy; possible radioactive iodine therapy after surgery

Stage II: Surgery; hormone therapy; possible radioactive iodine therapy after surgery

Stage III: Surgery; hormone therapy; possible radioactive iodine therapy or external-beam radiation therapy after surgery

Stage IV (advanced): Stage IV thyroid cancer is the most advanced stage of the disease. The cancer has spread beyond the thyroid to the lymph nodes and other organs, such as the bones or lungs.

Symptoms of advanced thyroid cancer are similar to those present when the disease was first diagnosed:

• A lump in the front of the neck, near the Adam’s apple
  
  
• Hoarseness
  
  
• Swollen glands, especially in the neck
  
  
• Difficulty swallowing
  
  
• Difficulty breathing
  
  
• Pain in the throat or neck
  
  
• A cough that persists and is not caused by a cold
  
  
• Bone pain, specifically when metastases develop in the skeleton

Treatment for advanced thyroid cancer may include a combination of surgery, hormone therapy, radioactive iodine therapy, external-beam radiation therapy, and chemotherapy. Radiation therapy may also be used to reduce pain and other problems. Patients with advanced thyroid cancer are also encouraged to consider participating in clinical trials.

Recurrent thyroid cancer

Recurrent thyroid cancer is cancer that comes back after treatment. Treatment for recurrent cancer will depend on the type of treatment given previously, the type of thyroid cancer, and where the cancer recurs. A combination of treatments will likely include: external-beam radiation therapy, chemotherapy, surgery, radioactive iodine treatment, hormone treatment, and clinical trials. In certain instances, a PET scan may be used to determine the extent of the cancer.

Find out more about common terms used during cancer treatment.