General Information About Parathyroid Cancer
Stages of Parathyroid Cancer
Recurrent Parathyroid Cancer
Treatment Option Overview
Treatment Options for Parathyroid Cancer

Localized Parathyroid Cancer Metastatic Parathyroid Cancer Recurrent Parathyroid Cancer

To Learn More About Parathyroid Cancer
Get More Information From NCI
Changes to This Summary (06/18/2008)
About PDQ

General Information About Parathyroid Cancer

Key Points for This Section

Parathyroid cancer is a rare disease in which malignant (cancer) cells form in the tissues of a parathyroid gland. Having certain inherited disorders can increase the risk of developing parathyroid cancer. Possible signs of parathyroid cancer include weakness, feeling tired, and a lump in the neck. Tests that examine the neck and blood are used to detect (find) and diagnose parathyroid cancer. Certain factors affect prognosis (chance of recovery) and treatment options.

Parathyroid cancer is a rare disease in which malignant (cancer) cells form in the tissues of a parathyroid gland.

The parathyroid glands are four pea-sized organs found in the neck near the thyroid gland. The parathyroid glands make parathyroid hormone (PTH or parathormone). PTH helps the body use and store calcium to keep the calcium in the blood at normal levels.

A parathyroid gland may become overactive and make too much PTH, a condition called hyperparathyroidism. Hyperparathyroidism can occur when a benign tumor (noncancer), called an adenoma, forms on one of the parathyroid glands, and causes it to grow and become overactive. Sometimes hyperparathyroidism can be caused by parathyroid cancer, but this is very rare.

The extra PTH causes:

• The calcium stored in the bones to move into the blood.
• The intestines to absorb more calcium from the food we eat.

This condition is called hypercalcemia (too much calcium in the blood).

The hypercalcemia caused by hyperparathyroidism is more serious and life-threatening than parathyroid cancer itself and treating hypercalcemia is as important as treating the cancer.

Having certain inherited disorders can increase the risk of developing parathyroid cancer.

Anything that increases the chance of getting a disease is called a risk factor. Risk factors for parathyroid cancer include the following rare disorders that are inherited (passed down from parent to child):

• Familial isolated hyperparathyroidism (FIHP).
• Multiple endocrine neoplasia type 1 (MEN1) syndrome.

Treatment with radiation therapy may increase the risk of developing a parathyroid adenoma.

Possible signs of parathyroid cancer include weakness, feeling tired, and a lump in the neck.

Most parathyroid cancer symptoms are caused by the hypercalcemia that develops. Symptoms of hypercalcemia include the following:

• Weakness.
• Feeling very tired.
• Nausea and vomiting.
• Loss of appetite.
• Weight loss for no known reason.
• Being much more thirsty than usual.
• Urinating much more than usual.
• Constipation.
• Trouble thinking clearly.

Other symptoms of parathyroid cancer include the following:

• Pain in the abdomen, side, or back that doesn't go away.
• Pain in the bones.
• A broken bone.
• A lump in the neck.
• Change in voice such as hoarseness.
• Trouble swallowing.

Other conditions may cause the same symptoms as parathyroid cancer. A doctor should be consulted if any of these problems occur.

Tests that examine the neck and blood are used to detect (find) and diagnose parathyroid cancer.

Once blood tests are done and hyperparathyroidism is diagnosed, imaging tests may be done to help find which of the parathyroid glands is overactive. Sometimes the parathyroid glands are hard to find and imaging tests are done to find exactly where they are.

Parathyroid cancer may be hard to diagnose because the cells of a benign parathyroid adenoma and a malignant parathyroid cancer look alike. The patient's symptoms, blood levels of calcium and parathyroid hormone, and characteristics of the tumor are also used to make a diagnosis.

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 anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
• Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances 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. To diagnose parathyroid cancer, the sample of blood is checked for its calcium level.
• Parathyroid hormone test: A procedure in which a blood sample is checked to measure the amount of parathyroid hormone released into the blood by the parathyroid glands. A higher than normal amount of parathyroid hormone can be a sign of disease.
• Sestamibi scan: A type of radionuclide scan used to find an overactive parathyroid gland. A small amount of a radioactive substance called technetium 99 is injected into a vein and travels through the bloodstream to the parathyroid gland. The radioactive substance will collect in the overactive gland and show up brightly on a special camera that detects radioactivity.
• 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.
• 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.
• Angiogram: A procedure to look at blood vessels and the flow of blood. A contrast dye is injected into the blood vessel. As the contrast dye moves through the blood vessel, x-rays are taken to see if there are any blockages.
• Venous sampling: A procedure in which a sample of blood is taken from specific veins and checked to measure the amounts of certain substances released into the blood by nearby organs and tissues. If imaging tests do not show which parathyroid gland is overactive, blood samples may be taken from veins near each parathyroid gland to find which one is making too much PTH.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

• Whether the calcium level in the blood can be controlled.
• The stage of the cancer.
• Whether the tumor and the capsule around the tumor can be completely removed by surgery.
• The patient's general health.

Stages of Parathyroid Cancer

Key Points for This Section

After parathyroid cancer has been diagnosed, tests are done to find out if cancer cells have spread to other parts of the body. There are three ways that cancer spreads in the body. There is no standard staging process for parathyroid cancer.

After parathyroid cancer has been diagnosed, tests are done to find out if cancer cells have spread to other parts of the body.

The process used to find out if cancer has spread to other parts of the body is called staging. The following imaging tests may be used to determine if cancer has spread to other parts of the body such as the lungs, liver, bone, heart, pancreas, or lymph nodes:

• 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).

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.

There is no standard staging process for parathyroid cancer.

Parathyroid cancer is described as either localized or metastatic:

• Localized parathyroid cancer is found in a parathyroid gland and may have spread to nearby tissues.
• Metastatic parathyroid cancer has spread to other parts of the body, such as the lungs, liver, bone, sac around the heart, pancreas, or lymph nodes.

Recurrent Parathyroid Cancer

Recurrent parathyroid cancer is cancer that has recurred (come back) after it has been treated. More than half of patients have a recurrence. The parathyroid cancer usually recurs between 2 and 5 years after the first surgery, but can recur up to 20 years later. It usually comes back in the tissues or lymph nodes of the neck. High blood calcium levels that appear after treatment may be the first sign of recurrence.

Treatment Option Overview

Key Points for This Section

There are different types of treatment for patients with parathyroid cancer. Treatment includes control of hypercalcemia (too much calcium in the blood) in patients who have an overactive parathyroid gland. Four types of standard treatment are used: Surgery Radiation therapy Chemotherapy Supportive care New types of treatment are being tested in clinical trials. Patients may want to think about taking part in a clinical trial. Patients can enter clinical trials before, during, or after starting their cancer treatment. Follow-up tests may be needed.

There are different types of treatment for patients with parathyroid cancer.

Different types of treatment are available for patients with parathyroid 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.

Treatment includes control of hypercalcemia (too much calcium in the blood) in patients who have an overactive parathyroid gland.

In order to reduce the amount of parathyroid hormone that is being made and control the level of calcium in the blood, as much of the tumor as possible is removed in surgery. For patients who cannot have surgery, medication may be used. See the PDQ summary on Hypercalcemia ¹ for more information.

Four types of standard treatment are used:

Surgery

Surgery (removing the cancer in an operation) is the most common treatment for parathyroid cancer that is in the parathyroid glands or has spread to other parts of the body. Because parathyroid cancer grows very slowly, cancer that has spread to other parts of the body may be removed by surgery in order to cure the patient or control the effects of the disease for a long time. Before surgery, treatment is given to control hypercalcemia.

The following surgical procedures may be used:

• En bloc resection: Surgery to remove the entire parathyroid gland and the capsule around it. Sometimes lymph nodes, half of the thyroid gland on the same side of the body as the cancer, and muscles, tissues, and a nerve in the neck are also removed.
• Tumor debulking: Surgery to remove as much of the tumor as possible. Sometimes, not all of the tumor can be removed.
• Metastasectomy: Surgery to remove any cancer that has spread to distant organs such as the lung.

Surgery for parathyroid cancer sometimes damages nerves of the vocal cords. There are treatments to help with speech problems caused by this nerve damage.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or stop 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.

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.

Supportive care

Supportive care is given to lessen the problems caused by the disease or its treatment. Supportive care for hypercalcemia caused by parathyroid cancer may include the following:

• Intravenous (IV) fluids.
• Drugs that increase how much urine the body makes.
• Drugs that stop the body from absorbing calcium from the food we eat.
• Drugs that stop the parathyroid gland from making parathyroid hormone.

New types of treatment are being tested in clinical trials.

Information about clinical trials is available from the NCI Web site ².

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.

Parathyroid cancer often recurs. Patients should have regular check-ups for the rest of their lives, to find and treat recurrences early.

Treatment Options for Parathyroid Cancer

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 localized parathyroid cancer may include the following:

• Surgery (en bloc resection).
• Surgery followed by radiation therapy.
• Radiation therapy.
• Supportive care to treat hypercalcemia (too much calcium in the blood).

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with localized parathyroid cancer ³. 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 ⁴.

Treatment of metastatic parathyroid cancer may include the following:

• Surgery (metastasectomy) to remove cancer from the places where it has spread.
• Surgery followed by radiation therapy.
• Radiation therapy.
• Chemotherapy.
• Supportive care to treat hypercalcemia (too much calcium in the blood).

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with metastatic parathyroid cancer ⁵. 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 ⁴.

Treatment of recurrent parathyroid cancer may include the following:

• Surgery (metastasectomy) to remove cancer from the places where it has recurred.
• Surgery (tumor debulking).
• Surgery followed by radiation therapy.
• Radiation therapy.
• Chemotherapy.
• Supportive care to treat hypercalcemia (too much calcium in the blood).

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with recurrent parathyroid cancer ⁶. 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 ⁴.

To Learn More About Parathyroid Cancer

For more information from the National Cancer Institute about parathyroid cancer, see the Parathyroid Cancer Home Page ⁷.

For general cancer information and other resources from the National Cancer Institute, see the following:

• What You Need to Know About™ Cancer - An Overview ⁸
• Understanding Cancer Series: Cancer ⁹
• Staging: Questions and Answers ¹⁰
• Chemotherapy and You: Support for People With Cancer ¹¹
• Radiation Therapy and You: Support for People With Cancer ¹²
• Coping with Cancer ¹³
• Support and Resources ¹⁴
• Cancer Library ¹⁵
• Information For Survivors/Caregivers/Advocates ¹⁶

Get More Information From NCI

Call 1-800-4-CANCER

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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 ¹⁹. 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.

Changes to This Summary (06/18/2008)

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 ²⁰ section.
• Information about patients taking part in clinical trials and about follow-up tests was added to the Treatment Option Overview ²¹ section.
• Links to ongoing clinical trials listed in NCI's PDQ Cancer Clinical Trials Registry were added to the Treatment Options ²² section.
• A new section called "To Learn More ²³" 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.

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 ¹⁸. 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 ²⁴. 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.

Glossary Terms

The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

A noncancerous tumor that starts in gland-like cells of the epithelial tissue (thin layer of tissue that covers organs, glands, and other structures within the body).

An x-ray of blood vessels. The person receives an injection of dye to outline the vessels on the x-ray.

A desire to satisfy a physical or mental need, such as for food, sex, or adventure.

Not cancer. Benign tumors may grow larger but do not spread to other parts of the body.

A noncancerous growth that does not invade nearby tissue or spread to other parts of the body.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

A procedure in which a sample of blood is examined to measure the amounts of certain substances made in the body. An abnormal amount of a substance can be a sign of disease in the organ or tissue that produces it.

A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.

Primary bone cancer is cancer that forms in cells of the bone. Some types of primary bone cancer are osteosarcoma, Ewing sarcoma, malignant fibrous histiocytoma, and chondrosarcoma. Secondary bone cancer is cancer that spreads to the bone from another part of the body (such as the prostate, breast, or lung).

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A mineral needed for healthy teeth, bones, and other body tissues. It is the most common mineral in the body. A deposit of calcium in body tissues, such as breast tissue, may be a sign of disease.

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

The smallest type of blood vessel. A capillary connects an arteriole (small artery) to a venule (small vein) to form a network of blood vessels in almost all parts of the body. The wall of a capillary is thin and leaky, and capillaries are involved in the exchange of fluids and gases between tissues and the blood.

In medicine, a sac of tissue and blood vessels that surrounds an organ, joint, or tumor. A capsule is also a form for medicine that is taken by mouth. It usually has a shell made of gelatin with the medicine inside.

A flexible tube used to deliver fluids into or withdraw fluids from the body.

A hollow area or hole. It may describe a body cavity (such as the space within the abdomen) or a hole in a tooth caused by decay.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Treatment with drugs that kill cancer cells.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.

A condition in which stool becomes hard, dry, and difficult to pass, and bowel movements don’t happen very often. Other symptoms may include painful bowel movements, and feeling bloated, uncomfortable, and sluggish.

A dye or other substance that helps show abnormal areas inside the body. It is given by injection into a vein, by enema, or by mouth. Contrast material may be used with x-rays, CT scans, MRI, or other imaging tests.

A series of detailed pictures of areas inside the body taken from different angles. The pictures are created by a computer linked to an x-ray machine. Also called CAT scan, computed tomography scan, computerized axial tomography scan, and computerized tomography.

To heal or restore health; a treatment to restore health.

The process of identifying a disease, such as cancer, from its signs and symptoms.

In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

A type of radiation therapy that uses a machine to aim high-energy rays at the cancer from outside of the body. Also called external-beam radiation therapy.

A substance that flows smoothly and takes the shape of its container. Liquids and gases are fluids.

Monitoring a person's health over time after treatment. This includes keeping track of the health of people who participate in a clinical study or clinical trial for a period of time, both during the study and after the study ends.

One of many chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in the laboratory.

Higher than normal levels of calcium in the blood. Some types of cancer increase the risk of hypercalcemia.

A condition in which the parathyroid gland (one of four pea-sized organs found on the thyroid) makes too much parathyroid hormone. This causes a loss of calcium from the bones and an increased level of calcium in the blood. Symptoms include bone pain and kidney problems.

In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as x-rays (high-energy radiation), ultrasound (high-energy sound waves), and radio waves.

Transmitted through genes that have been passed from parents to their offspring (children).

Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."

A type of radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor. Also called brachytherapy, implant radiation therapy, and radiation brachytherapy.

The long, tube-shaped organ in the abdomen that completes the process of digestion. The intestine has two parts, the small intestine and the large intestine. Also called bowel.

Into or within a vein. Intravenous usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called IV.

Cancer that has spread beyond the layer of tissue in which it developed and is growing into surrounding, healthy tissues. Also called infiltrating cancer.

A large organ located in the upper abdomen. The liver cleanses the blood and aids in digestion by secreting bile.

Restricted to the site of origin, without evidence of spread.

One of a pair of organs in the chest that supplies the body with oxygen, and removes carbon dioxide from the body.

The clear fluid that travels through the lymphatic system and carries cells that help fight infections and other diseases. Also called lymphatic fluid.

A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.

A thin tube that carries lymph (lymphatic fluid) and white blood cells through the lymphatic system. Also called lymphatic vessel.

The tissues and organs that produce, store, and carry white blood cells that fight infections and other diseases. This system includes the bone marrow, spleen, thymus, lymph nodes, and lymphatic vessels (a network of thin tubes that carry lymph and white blood cells). Lymphatic vessels branch, like blood vessels, into all the tissues of the body.

Cancerous. Malignant tumors can invade and destroy nearby tissue and spread to other parts of the body.

A legal drug that is used to prevent, treat, or relieve symptoms of a disease or abnormal condition.

Surgery to remove one or more metastases (tumors formed from cells that have spread from the primary tumor). When all metastases are removed, it is called a complete metastasectomy.

The spread of cancer from one part of the body to another. A tumor formed by cells that have spread is called a “metastatic tumor” or a “metastasis.” The metastatic tumor contains cells that are like those in the original (primary) tumor. The plural form of metastasis is metastases (meh-TAS-tuh-SEEZ).

Having to do with metastasis, which is the spread of cancer from one part of the body to another.

A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called magnetic resonance imaging, NMRI, and nuclear magnetic resonance imaging.

A rare, inherited disorder that affects the endocrine glands and can cause tumors in the parathyroid and pituitary glands and the pancreas. These tumors (usually benign) cause the glands to secrete high levels of hormones, which can lead to other medical problems, such as kidney stones, fertility problems, and severe ulcers. In some cases, tumors inside the pancreas can become cancerous. Also called MEN1 syndrome, multiple endocrine adenomatosis, and Wermer syndrome.

The National Cancer Institute, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. The National Cancer Institute conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the National Cancer Institute Web site at http://www.cancer.gov. Also called NCI.

A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.

NCI, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. It conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the NCI Web site at http://www.cancer.gov. Also called National Cancer Institute.

A bundle of fibers that receives and sends messages between the body and the brain. The messages are sent by chemical and electrical changes in the cells that make up the nerves.

A part of the body that performs a specific function. For example, the heart is an organ.

A glandular organ located in the abdomen. It makes pancreatic juices, which contain enzymes that aid in digestion, and it produces several hormones, including insulin. The pancreas is surrounded by the stomach, intestines, and other organs.

A rare cancer that forms in tissues of one or more of the parathyroid glands (four pea-sized glands in the neck that make parathyroid hormone, which helps the body store and use calcium).

One of four pea-sized glands found on the surface of the thyroid. The parathyroid hormone made by these glands increases the calcium level in the blood.

A substance made by the parathyroid gland that helps the body store and use calcium. A higher-than-normal amount of parathyroid hormone causes high levels of calcium in the blood and may be a sign of disease. Also called parathormone, parathyrin, and PTH.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

An exam of the body to check for general signs of disease.

The original tumor.

The likely outcome or course of a disease; the chance of recovery or recurrence.

Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

Giving off radiation.

A small, radioactive pellet that is placed in or near a tumor. Cancer cells are killed by the energy given off as the radioactive material breaks down and becomes more stable.

A procedure that produces pictures (scans) of structures inside the body, including areas where there are cancer cells. Radionuclide scanning is used to diagnose, stage, and monitor disease. A small amount of a radioactive chemical (radionuclide) is injected into a vein or swallowed. Different radionuclides travel through the blood to different organs. A machine with a special camera moves over the person lying on a table and detects the type of radiation given off by the radionuclides. A computer forms an image of the areas where the radionuclide builds up. These areas may contain cancer cells. Also called scintigraphy.

To come back or to return.

Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrent cancer.

Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrence.

Treatment with anticancer drugs directed to a specific area of the body.

A procedure that uses surgery to remove tissue or part or all of an organ.

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

A picture of structures inside the body. Scans often used in diagnosing, staging, and monitoring disease include liver scans, bone scans, and computed tomography (CT) or computerized axial tomography (CAT) scans and magnetic resonance imaging (MRI) scans. In liver scanning and bone scanning, radioactive substances that are injected into the bloodstream collect in these organs. A scanner that detects the radiation is used to create pictures. In CT scanning, an x-ray machine linked to a computer is used to produce detailed pictures of organs inside the body. MRI scans use a large magnet connected to a computer to create pictures of areas inside the body.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

A computer picture of areas inside the body created by bouncing high-energy sound waves (ultrasound) off internal tissues or organs. Also called ultrasonogram.

The bones, muscles, tendons, and other tissues that reach from the base of the skull to the tailbone. The spinal column encloses the spinal cord and the fluid surrounding the spinal cord. Also called backbone, spine, and vertebral column.

The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.

Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from the original site to other parts of the body. It is important to know the stage of the disease in order to plan the best treatment.

In medicine, treatment that experts agree is appropriate, accepted, and widely used. Health care providers are obligated to provide patients with standard therapy. Also called best practice and standard of care.

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of supportive care is to prevent or treat as early as possible the symptoms of a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called comfort care, palliative care, and symptom management.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

Treatment with anticancer drugs that travel through the blood to cells all over the body.

A gland located beneath the voice box (larynx) that produces thyroid hormone. The thyroid helps regulate growth and metabolism.

A group or layer of cells that work together to perform a specific function.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.

Surgical removal of as much of a tumor as possible. Tumor debulking may increase the chance that chemotherapy or radiation therapy will kill all the tumor cells. It may also be done to relieve symptoms or help the patient live longer. Also called debulking.

A procedure in which high-energy sound waves are bounced off internal tissues or organs and make echoes. The echo patterns are shown on the screen of an ultrasound machine, forming a picture of body tissues called a sonogram. Also called ultrasonography.

Fluid containing water and waste products. Urine is made by the kidneys, stored in the bladder, and leaves the body through the urethra.

A blood vessel that carries blood to the heart from tissues and organs in the body.

One of two small bands of muscle within the larynx that vibrates to produce the voice.

To eject some or all of the contents of the stomach through the mouth.

A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.