Thyroid Cancer

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

Treatment overview

In cancer care, different types of doctors often work together to create a patient's overall treatment plan that combines different types of treatments. This is called a multidisciplinary team. For thyroid cancer, this may include a surgeon, endocrinologist (a doctor specializing in problems with glands and the endocrine system), medical oncologist, and radiation oncologist.

Thyroid cancer is commonly treated by one or a combination of treatments, including surgery, hormone treatment, radioactive iodine, external-beam radiation therapy, and/or chemotherapy. Descriptions of these options for thyroid cancer are listed below, followed by an outline of common cancer treatments given by stage of disease (see Staging).

Treatment options and recommendations depend on several factors, including the type and stage of cancer, possible side effects, and the patient's preferences and overall health. 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 regarding which combination of treatments to use and the timing when treatments are done. 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. Learn more about making treatment decisions.

Surgery

Surgery is the removal of the tumor and surrounding tissue during an operation. It is the main treatment for most people with thyroid cancers. A surgical oncologist is a doctor who specializes in treating cancer using surgery. Depending on the size of the nodule, surgical options include:

Total thyroidectomy. This surgery removes the entire thyroid gland.

Near-total thyroidectomy. Also called subtotal thyroidectomy, this is surgery to remove the thyroid gland except for a small part.

Lobectomy. This surgery removes 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. This is surgery to remove the lymph nodes in the neck that can also be called a lymphadenectomy.

Complications of surgery may include damage to the nearby 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. Also, be sure to talk with your doctor about all other medications (including dietary supplements, such as iron or calcium) you are taking to avoid interactions with your thyroid hormone replacement. Read more about tips to take your medication correctly.

Thyroid pills may have a 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. Bone loss (osteoporosis) is also possible. Hypothyroidism (too little hormone) may cause fatigue, weight gain, and dry skin and hair; patients may also feel cold. The amount or dose 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, a type of radiation therapy called 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. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist.

This treatment is an option for most people with the papillary and follicular types. A small test dose may be given prior to full treatment, to be sure the tumor cells will absorb the I-131. 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 follow a low-iodine 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 receive injections of recombinant TSH (Thyrogen) while taking the hormone replacement. If the hormone therapy is stopped during the preparation period, the patient will likely experience side effects due to hypothyroidism (see above).

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 (inability to produce a child), especially in men. It is recommended that women avoid pregnancy for at least one year after radioactive iodine treatment. There is a risk of secondary cancers with the use of I-131 (see After 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.

External-beam radiation therapy

External-beam radiation is another type of radiation therapy in which high-energy x-rays are given from a machine outside the body to kill cancer cells. An external-beam radiation therapy regimen (schedule) usually consists of a specific number of treatments given oven a set period of time. When used to treat thyroid cancer, radiation therapy is usually given as outpatient therapy, either in a hospital or clinic, five days a week for about five to six weeks.

For thyroid cancer, external-beam radiation therapy is used only in certain circumstances, typically when advanced thyroid cancer has not responded to radioactive iodine therapy (see above). 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. Learn more about external-beam radiation therapy.

Chemotherapy and Targeted therapy

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, usually aimed at stopping cancer cells' ability to grow and divide throughout the body. Chemotherapy is given by a medical oncologist, a doctor who specializes in treating cancer with medication. A chemotherapy regimen (schedule) usually consists of a specific number of cycles given over a set period of time. A patient may receive one drug at a time or combinations of different drugs at the same time.

The goal of chemotherapy can be to destroy cancer remaining after surgery, slow the tumor's growth, or reduce symptoms. The side effects of chemotherapy depend on the individual and the dose used, but they can include fatigue, risk of infection, nausea and vomiting, loss of appetite, and diarrhea. These side effects usually go away once treatment is finished.

Targeted therapy is a treatment that targets the cancer's specific genes, proteins, or the tissue environment that contributes to cancer growth and survival. This type of treatment blocks the growth and spread of cancer cells while limiting damage to normal cells, usually leading to fewer side effects than other cancer medications. Recent studies show that not all tumors have the same targets. To find the most effective treatment, your doctor may run tests to identify the genes, proteins, and other factors in your tumor. As a result, doctors can better match each patient with the most effective treatment whenever possible. Many research studies are taking place now to find out more about specific molecular targets and new treatments directed at them.

For medullary thyroid cancer treatment, the U.S. Food and Drug Administration (FDA) in 2011 approved vandetanib tablets (Caprelsa, zd6474), which is a type of targeted therapy known as a tyrosine kinase inhibitor. Specifically, vandetanib is now a standard treatment for adults when MTC is not able to be removed surgically (unresectable), the disease is worsening, or if MTC has spread to other parts of the body (metastatic). The medication is given as a daily pill; the typical daily dose of vandetanib is 300 mg. Common side effects include diarrhea and colon inflammation, skin rash, nausea, high blood pressure, headache, fatigue, loss of appetite, and stomach pain. Additionally, more serious side effects such as respiratory and heart problems can occur. Before treatment begins, be sure to talk to your doctor about potential side effects, and let your doctor know right away about any side effects you experience during treatment. Blood tests, including serum potassium, calcium, magnesium, and TSH levels (see Diagnosis), may be done to monitor the body's reaction to this medication on a regular basis.

At this time, the use of other, systemic chemotherapy and targeted therapy 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). See the Current Research section for more information.

Learn more about chemotherapy, targeted treatments, 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.

Recurrent thyroid cancer

Once your treatment is complete and there is a remission (absence of cancer symptoms; also called “no evidence of disease” or NED), talk with your doctor about the possibility of the cancer returning. Many survivors feel worried or anxious that the cancer will come back. Learn more about coping with this fear.

If the cancer does return after the original treatment, it is called recurrent cancer. It may come back in the same place (called a local recurrence), nearby (regional recurrence), or in another place (distant recurrence).

When this occurs, a cycle of testing will begin again to learn as much as possible about the recurrence. After testing is done, you and your doctor will talk about your treatment options. Often the treatment plan will include the therapies described above (such as surgery, chemotherapy, targeted therapy, and radiation therapy) but may be used in a different combination or given at a different pace. Your doctor may also suggest clinical trials that are studying new ways to treat this type of recurrent cancer.

People with recurrent cancer often experience emotions such as disbelief or fear. Patients are encouraged to talk with their health care team about these feelings and ask about support services to help them cope. Learn more about dealing with cancer recurrence.

Stage IV thyroid cancer

If the cancer has spread beyond the thyroid to other organs, such as the bones or lungs, this is called metastatic or Stage IV thyroid cancer. Also, all anaplastic thyroid tumors are classified as stage IV at the time of diagnosis, regardless of tumor size, location, or spread.

Patients with this diagnosis are encouraged to talk with doctors who are experienced in treating this stage of cancer, because there can be different opinions about the best treatment plan. Learn more about seeking a second opinion before starting treatment, so you are comfortable with the treatment plan chosen. This discussion may include clinical trials.

Your health care team may recommend a treatment plan that includes a combination of surgery, hormone therapy, radioactive iodine therapy, external-beam radiation therapy, targeted therapy, and chemotherapy. Clinical trials on new treatment approaches may also be recommended.

In addition to treatment to slow, stop, or eliminate the cancer (also called disease-directed treatment), an important part of cancer care is relieving a person's symptoms and side effects. It includes supporting the patient with his or her physical, emotional, and social needs, an approach called palliative or supportive care. People often receive disease-directed therapy and treatment to ease symptoms at the same time.

Although treatment is successful for the majority of people with thyroid cancer, sometimes it is not. If disease-directed treatment is not successful, this may also be called advanced cancer. This diagnosis is stressful, and it may be difficult to discuss. However, it is important to have open and honest conversations with your doctor and health care team to express your feelings, preferences, and concerns. The health care team is there to help, and many team members have special skills, experience, and knowledge to support patients and their families. Learn more about advanced cancer care planning.

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 later stage disease may be treated with surgery as well, but other treatments may be done first. Clinical trials may be recommended at any stage as a treatment option.

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: Surgery, hormone therapy, radioactive iodine therapy, external-beam radiation therapy, targeted therapy, and chemotherapy. Radiation therapy may also be used to reduce pain and other problems.

Find out more about common terms used during cancer treatment.