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Table of Contents General Information About Thyroid Cancer
Stages of Thyroid Cancer
Recurrent Thyroid Cancer
Treatment Option Overview
Treatment Options by Stage
Treatment Options for Recurrent Thyroid Cancer
To Learn More About Thyroid Cancer
Get More Information From NCI
Changes to This Summary (05/23/2008)
About PDQ
General Information About Thyroid Cancer
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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:
- Control heart rate, body temperature, and how quickly food is changed into energy (metabolism).
- Control the amount of calcium in the blood.
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:
- A lump in the neck.
- Trouble breathing.
- Trouble swallowing.
- Hoarseness.
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:
- Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or swelling in the neck, voice box, and lymph nodes, and anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
- Laryngoscopy: A procedure in which the doctor checks the larynx (voice box) with a mirror or with a laryngoscope. A laryngoscope is a thin, tube-like instrument with a light and a lens for viewing. A thyroid tumor may press on vocal cords. The laryngoscopy is done to see if the vocal cords are moving normally.
- Blood hormone studies: A procedure in which a blood sample is checked to measure the amounts of certain hormones released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it. The blood may be checked for abnormal levels of thyroid-stimulating hormone (TSH). TSH is made by the pituitary gland in the brain. It stimulates the release of thyroid hormone and controls how fast follicular thyroid cells grow.
The blood may also be checked for high levels of the hormone calcitonin.
- Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances, such as calcium, released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it.
- Radioactive iodine scan (RAI scan): A procedure to find areas in the body where thyroid cancer cells may be dividing quickly. Radioactive iodine (RAI) is used because only thyroid cells take up iodine. A very small amount of RAI is swallowed, travels through the blood, and collects in thyroid tissue and thyroid cancer cells anywhere in the body. Abnormal thyroid cells take up less iodine than normal thyroid tissue. Areas that do not absorb the iodine normally (cold spots) show up lighter in the picture made by the scan. Cold spots can be either benign (not cancer) or malignant, so a biopsy is done to find out if they are cancer.
- Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. The picture can be printed to be looked at later. This procedure can show the size of a thyroid tumor and whether it is solid or a fluid -filled cyst. Ultrasound may be used to guide a fine-needle aspiration biopsy.
- CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
- MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
- PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
- Fine-needle aspiration biopsy of the thyroid: The removal of thyroid tissue using a thin needle. The needle is inserted through the skin into the thyroid. Several tissue samples are removed from different parts of the thyroid. A pathologist views the tissue samples under a microscope to look for cancer cells. Because the type of thyroid cancer can be hard to diagnose, patients should ask to have biopsy samples checked by a pathologist who has experience diagnosing thyroid cancer.
- Surgical biopsy: The removal of the thyroid nodule or one lobe of the thyroid during surgery so the cells and tissues can be viewed under a microscope by a pathologist to check for signs of cancer. Because the type of thyroid cancer can be hard to diagnose, patients should ask to have biopsy samples checked by a pathologist who has experience diagnosing thyroid cancer.
Certain factors affect prognosis (chance of recovery) and treatment options.
The prognosis (chance of recovery) and treatment options depend on the following:
- The age of the patient.
- The type of thyroid cancer.
- The stage of the cancer.
- The patient's general health.
- Whether the patient has multiple endocrine neoplasia type 2B (MEN 2B).
- Whether the cancer has just been diagnosed or has recurred (come back).
Back to Top Stages of Thyroid Cancer
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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:
- CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
- MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
- Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. The picture can be printed to be looked at later.
- Radioactive iodine scan (RAI scan): A procedure to find areas in the body where thyroid cancer cells may be dividing quickly. Radioactive iodine (RAI) is used because only thyroid cells take up iodine. A very small amount of RAI is swallowed, travels through the blood, and collects in thyroid tissue and thyroid cancer cells anywhere in the body. Abnormal thyroid cells take up less iodine than normal thyroid cells. Areas that do not absorb the iodine normally (cold spots) show up lighter in the picture made by the scan. Cold spots can be either benign (not cancer) or malignant, so more tests are needed to find out if they are cancer. A scan of the whole body may be done to find out the stage of the cancer.
- Lymph node biopsy: The removal of all or part of a lymph node. A pathologist views the tissue under a microscope to look for cancer cells.
- Bone scan: A procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner.
- Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
There are three ways that cancer spreads in the body.
The three ways that cancer spreads in the body are:
- Through tissue. Cancer invades the surrounding normal tissue.
- Through the lymph system. Cancer invades the lymph system and travels through the lymph vessels to other places in the body.
- Through the blood. Cancer invades the veins and capillaries and travels through the blood to other places in the body.
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:
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| 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:
- the tumor is larger than 4 centimeters or the tumor is any size and cancer has spread to tissues just outside the thyroid, but not to lymph nodes; or
- the tumor is any size and cancer may have spread to tissues just outside the thyroid and has spread to lymph nodes near the trachea or the larynx (voice box).
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.
Back to Top Recurrent Thyroid Cancer
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.
Back to Top Treatment Option Overview
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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:
- Lobectomy: Removal of the lobe in which thyroid cancer is found. Biopsies of lymph nodes in the area may be done to see if they contain cancer.
- Near-total thyroidectomy: Removal of all but a very small part of the thyroid.
- Total thyroidectomy: Removal of the whole thyroid.
- Lymphadenectomy: Removal of lymph nodes in the neck that contain cancer.
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.
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.
Back to Top Treatment Options by Stage
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.
Stages I and II Papillary and Follicular Thyroid Cancer
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, stage I follicular thyroid cancer, stage II papillary thyroid cancer and stage II follicular thyroid cancer. 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.
Stage III Papillary and Follicular Thyroid Cancer
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 and stage III follicular thyroid cancer. 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.
Stage IV Papillary and Follicular Thyroid Cancer
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 and stage IV follicular thyroid cancer. 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.
Medullary Thyroid Cancer
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. 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.
Anaplastic Thyroid Cancer
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. 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.
Back to Top Treatment Options for Recurrent Thyroid Cancer
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. 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.
Back to Top To Learn More About Thyroid Cancer
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:
Back to Top Get More Information From NCI
Call 1-800-4-CANCER
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 a.m. to 4:30 p.m. Deaf and hard-of-hearing callers with TTY equipment may call 1-800-332-8615. The call is free and a trained Cancer Information Specialist is available to answer your questions.
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For more information from the NCI, please write to this address:
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Search the NCI Web site
The NCI Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use our “Best Bets” search box in the upper right hand corner of each Web page. The results that are most closely related to your search term will be listed as Best Bets at the top of the list of search results.
There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.
Find Publications
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237), TTY at 1-800-332-8615.
Back to Top Changes to This Summary (05/23/2008)
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.
Several enhancements have been made to this summary to better explain certain medical concepts and to help readers find information about clinical trials. The following changes were made:
- Text describing the way cancer spreads in the body was added to the Stages section.
- Information about patients taking part in clinical trials and about follow-up tests was added to the Treatment Option Overview section.
- Links to ongoing clinical trials listed in NCI’s PDQ Cancer Clinical Trials Registry were added to the Treatment Options section.
- A new section called "To Learn More" was added. It includes links to more information about this type of cancer and about cancer in general.
- The “Get More Information from NCI” section (originally called “To Learn More”) was revised.
Back to Top About PDQ
PDQ is a comprehensive cancer database available on NCI's Web site.
PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at NCI's Web site. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.
PDQ contains cancer information summaries.
The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries are available in two versions. The health professional versions provide detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions provide current and accurate cancer information.
The PDQ cancer information summaries are developed by cancer experts and reviewed regularly.
Editorial Boards made up of experts in oncology and related specialties are responsible for writing and maintaining the cancer information summaries. The summaries are reviewed regularly and changes are made as new information becomes available. The date on each summary ("Date Last Modified") indicates the time of the most recent change.
PDQ also contains information on clinical trials.
A clinical trial is a study to answer a scientific question, such as whether one treatment is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. During treatment clinical trials, information is collected about the effects of a new treatment and how well it works. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." 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.
Listings of clinical trials are included in PDQ and are available online at NCI's Web site. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237); TTY at 1-800-332-8615.
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