Masonic Cancer Center, University of Minnesota
Thyroid cancer is a disease in which malignant (cancer) cells form in the tissues of the thyroid gland.
The thyroid is a gland at the base of the throat near the trachea (windpipe). It is shaped like a butterfly, with a right lobe and a left lobe. The isthmus, a thin piece of tissue, connects the two lobes. A healthy thyroid is a little larger than a quarter. It usually cannot be felt through the skin. The thyroid uses iodine, a mineral found in some foods and in iodized salt, to help make several hormones. Thyroid hormones do the following:
There are four main types of thyroid cancer:
Age, gender, and exposure to radiation can affect the risk of developing thyroid cancer.
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. People who think they may be at risk should discuss this with their doctor. Risk factors for thyroid cancer include the following:
Medullary thyroid cancer is sometimes caused by a change in a gene that is passed from parent to child.
The genes in cells carry hereditary information from parent to child. A certain change in a gene that is passed from parent to child (inherited) may cause medullary thyroid cancer. A test has been developed that can find the changed gene before medullary thyroid cancer appears. The patient is tested first to see if he or she has the changed gene. If the patient has it, other family members may also be tested. Family members, including young children, who have the changed gene can decrease the chance of developing medullary thyroid cancer by having a thyroidectomy (surgery to remove the thyroid).
Possible signs of thyroid cancer include a swelling or lump in the neck.
Thyroid cancer may not cause early symptoms. It is sometimes found during a routine physical exam. Symptoms may occur as the tumor gets bigger. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:
Tests that examine the thyroid, neck, and blood are used to detect (find) and diagnose thyroid cancer.
The following tests and procedures may be used:
Certain factors affect prognosis (chance of recovery) and treatment options.
The prognosis (chance of recovery) and treatment options depend on the following:
After thyroid cancer has been diagnosed, tests are done to find out if cancer cells have spread within the thyroid or to other parts of the body.
The process used to find out if cancer has spread within the thyroid or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. The following tests and procedures may be used in the staging process:
There are three ways that cancer spreads in the body.
The three ways that cancer spreads in the body are:
When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
The following stages are used for papillary and follicular thyroid cancer in patients younger than 45 years:
Stage I
In stage I papillary and follicular thyroid cancer, the tumor is any size, may be in the thyroid, or may have spread to nearby tissues and lymph nodes. Cancer has not spread to other parts of the body.
Stage II
In stage II papillary and follicular thyroid cancer, cancer has spread from the thyroid to other parts of the body, such as the lungs or bone.
The following stages are used for papillary and follicular thyroid cancer in patients 45 years and older:

Pea, peanut, walnut, and lime show tumor sizes.
Stage I
In stage I papillary and follicular thyroid cancer, cancer is found only in the thyroid and the tumor is 2 centimeters or smaller.
Stage II
In stage II papillary and follicular thyroid cancer, cancer is only in the thyroid and the tumor is larger than 2 centimeters but not larger than 4 centimeters.
Stage III
In stage III papillary and follicular thyroid cancer, either of the following is found:
Stage IV
Stage IV papillary and follicular thyroid cancer is divided into stages IVA, IVB, and IVC.
The following stages are used for medullary thyroid cancer:
Stage 0
Stage 0 medullary thyroid cancer is found only with a special screening test. No tumor can be found in the thyroid.
Stage I
Stage I medullary thyroid cancer is found only in the thyroid and is 2 centimeters or smaller.
Stage II
Stage II medullary thyroid cancer is only in the thyroid and is larger than 2 centimeters but not larger than 4 centimeters.
Stage III
In stage III medullary thyroid cancer:
Stage IV
Stage IV medullary thyroid cancer is divided into stages IVA, IVB, and IVC.
Anaplastic thyroid cancer is considered stage IV thyroid cancer.
Anaplastic thyroid cancer grows quickly and has usually spread within the neck when it is found. Stage IV anaplastic thyroid cancer is divided into stages IVA, IVB, and IVC.
Recurrent thyroid cancer is cancer that has recurred (come back) after it has been treated. Thyroid cancer may come back in the thyroid or in other parts of the body.
There are different types of treatment for patients with thyroid cancer.
Different types of treatment are available for patients with thyroid cancer. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
Four types of standard treatment are used:
Surgery
Surgery is the most common treatment of thyroid cancer. One of the following procedures may be used:
Radiation therapy, including radioactive iodine therapy
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.
Radiation therapy may be given after surgery to kill any thyroid cancer cells that were not removed. Follicular and papillary thyroid cancers are sometimes treated with radioactive iodine (RAI) therapy. Higher doses than the amounts used to diagnose thyroid cancer are used. RAI is taken by mouth and collects in any remaining thyroid tissue, including thyroid cancer cells that have spread to other places in the body. Since only thyroid tissue takes up iodine, the RAI destroys thyroid tissue and thyroid cancer cells without harming other tissue. Before a full treatment dose of RAI is given, a small test-dose is given to see if the tumor takes up the iodine.
Chemotherapy
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.
Thyroid hormone therapy
Hormone therapy is a cancer treatment that removes hormones or blocks their action and stops cancer cells from growing. Hormones are substances made by glands in the body and circulated in the bloodstream. In the treatment of thyroid cancer, drugs may be given to prevent the body from making thyroid-stimulating hormone (TSH), a hormone that can increase the chance that thyroid cancer will grow or recur.
Also, because thyroid cancer treatment kills thyroid cells, the thyroid is not able to make enough thyroid hormone. Patients are given thyroid hormone replacement pills.
New types of treatment are being tested in clinical trials.
Information about clinical trials is available from the NCI Web site (see also: clinical trials at the Masonic Cancer Center) .
Targeted therapy
Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells.
Tyrosine kinase inhibitor therapy is a type of targeted therapy being studied in the treatment of thyroid cancer. Tyrosine kinase inhibitors block signals needed for tumors to grow.
Patients may want to think about taking part in a clinical trial.
For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.
Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.
Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.
Patients can enter clinical trials before, during, or after starting their cancer treatment.
Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.
Clinical trials are taking place in many parts of the country. See the Treatment Options section that follows for links to current treatment clinical trials. These have been retrieved from NCI's clinical trials database.
Follow-up tests may be needed.
Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests. This is sometimes called re-staging.
Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.
A link to a list of current clinical trials is included for each treatment section. For some types or stages of cancer, there may not be any trials listed. Check with your doctor for clinical trials that are not listed here but may be right for you.
Treatment of stage I and II papillary and follicular thyroid cancer may include the following:
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with stage I papillary thyroid cancer (see also: clinical trials at the Masonic Cancer Center) , stage I follicular thyroid cancer (see also: clinical trials at the Masonic Cancer Center) , stage II papillary thyroid cancer (see also: clinical trials at the Masonic Cancer Center) and stage II follicular thyroid cancer (see also: clinical trials at the Masonic Cancer Center) . For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site.
Treatment of stage III papillary and follicular thyroid cancer is usually total thyroidectomy. Cancer that has spread outside the thyroid, as well as any lymph nodes that have cancer in them, will also be removed. Radioactive iodine therapy or external radiation therapy may be given after surgery.
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with stage III papillary thyroid cancer (see also: clinical trials at the Masonic Cancer Center) and stage III follicular thyroid cancer (see also: clinical trials at the Masonic Cancer Center) . For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site.
Treatment of stage IV papillary and follicular thyroid cancer that has spread only to the lymph nodes can often be cured. When cancer has spread to other places in the body, such as the lungs and bone, treatment usually does not cure the cancer, but can relieve symptoms and improve the quality of life. Treatment may include the following:
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with stage IV papillary thyroid cancer (see also: clinical trials at the Masonic Cancer Center) and stage IV follicular thyroid cancer (see also: clinical trials at the Masonic Cancer Center) . For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site.
Treatment may include the following:
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with thyroid gland medullary carcinoma (see also: clinical trials at the Masonic Cancer Center) . For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site.
Treatment may include the following:
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with anaplastic thyroid cancer (see also: clinical trials at the Masonic Cancer Center) . For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site.
Treatment of recurrent thyroid cancer may include the following:
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with recurrent thyroid cancer (see also: clinical trials at the Masonic Cancer Center) . For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site.
For more information from the National Cancer Institute about thyroid cancer, see the following:
For general cancer information and other resources from the National Cancer Institute, see the following:
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Changes were made to this summary to match those made to the health professional version.
Date last modified: 2009-09-23