National Cancer Institute

The oropharynx is the middle part of the pharynx (throat) behind the mouth, and includes the back one-third of the tongue, the soft palate, the side and back walls of the throat, and the tonsils. The pharynx is a hollow tube about 5 inches long that starts behind the nose and ends at the top of the trachea (windpipe) and esophagus (the tube that goes from the throat to the stomach). Air and food pass through the pharynx on the way to the trachea or the esophagus.

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Anatomy of the pharynx; drawing shows the nasopharynx, oropharynx, and hypopharynx. Also shown are the nasal cavity, oral cavity, esophagus, trachea, and larynx.

Anatomy of the pharynx (throat). The three parts of the pharynx are the nasopharynx, oropharynx, and hypopharynx.

Most oropharyngeal cancers are squamous cell carcinomas. Squamous cells are the thin, flat cells that line the inside of the oropharynx.

Oropharyngeal cancer is a type of head and neck cancer.

Use of tobacco products and drinking too much alcohol can increase the risk of developing oropharyngeal 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 include the following:

Smoking and chewing tobacco.
Heavy alcohol use.
A diet low in fruits and vegetables.
Drinking maté, a stimulant drink common in South America.
Chewing betel quid, a stimulant commonly used in parts of Asia.
Being infected with human papillomavirus (HPV).

Possible signs of oropharyngeal cancer include a sore throat and a lump in the neck.

These and other symptoms may be caused by oropharyngeal cancer. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

A sore throat that does not go away.
A dull pain behind the breastbone.
Cough.
Trouble swallowing.
Weight loss for no known reason.
Ear pain.
A lump in the back of the mouth, throat, or neck.
A change in voice.

Tests that examine the mouth and throat are used to help detect (find), diagnose, and stage oropharyngeal 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 swollen lymph nodes in the neck or anything else that seems unusual. The doctor does a complete exam of the mouth and neck and looks down the throat with a small, long-handled mirror to check for abnormal areas. A history of the patient’s health habits and past illnesses and treatments will also be taken.
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).
X-rays: An x-ray of the organs and bones. An x-ray is a type of energy beam that can go through the body and onto film, making pictures of areas inside the body.
PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radionuclide 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.
Endoscopy: A procedure to look at organs and tissues inside the body to check for abnormal areas. An endoscope is inserted through the patient’s nose or mouth to look at areas in the throat that cannot be seen during a physical exam of the throat. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue or lymph node samples, which are checked under a microscope for signs of disease.
Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer.

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

The prognosis (chance of recovery) depends on the following:

The stage and grade of the cancer.
The location of the tumor.
Whether the tumor is associated with HPV infection.

Treatment options depend on the following:

The stage and grade of the cancer.
The location of the tumor.
The patient's general health.

Stages of Oropharyngeal Cancer

Key Points for This Section

After oropharyngeal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the oropharynx or to other parts of the body.
There are three ways that cancer spreads in the body.
The following stages are used for oropharyngeal cancer:

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

The process used to find out if cancer has spread within the oropharynx 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 results of some of the tests ² used to diagnose oropharyngeal cancer are often used to stage the disease.

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 oropharyngeal cancer:

Stage 0 (Carcinoma in Situ)

In stage 0, abnormal cells are found in the lining of the oropharynx. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.

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Tumor size compared to everyday objects; shows various measurements of a tumor compared to a pea, peanut, walnut, and lime

Pea, peanut, walnut, and lime show tumor sizes.

Stage I

In stage I, cancer has formed and is 2 centimeters or smaller and is found in the oropharynx only.

Stage II

In stage II, the cancer is larger than 2 centimeters but not larger than 4 centimeters and is found in the oropharynx only.

Stage III

In stage III, the cancer is either:

4 centimeters or smaller; cancer has spread to one lymph node on the same side of the neck as the tumor and the lymph node is 3 centimeters or smaller; or
larger than 4 centimeters or has spread to the epiglottis (the flap that covers the trachea during swallowing). Cancer may have spread to one lymph node on the same side of the neck as the tumor and the lymph node is 3 centimeters or smaller.

Stage IV

Stage IV is divided into stage IVA, IVB, and IVC as follows:

In stage IVA, cancer:
- has spread to the larynx, front part of the roof of the mouth, lower jaw, or muscles that move the tongue or are used for chewing. Cancer may have spread to one lymph node on the same side of the neck as the tumor and the lymph node is 3 centimeters or smaller; or
- has spread to one lymph node on the same side of the neck as the tumor (the lymph node is larger than 3 centimeters but not larger than 6 centimeters) or to more than one lymph node anywhere in the neck (the lymph nodes are 6 centimeters or smaller), and one of the following is true:
  - tumor in the oropharynx is any size and may have spread to the epiglottis (the flap that covers the trachea during swallowing); or
  - tumor has spread to the larynx, front part of the roof of the mouth, lower jaw, or muscles that move the tongue or are used for chewing.
In stage IVB, the tumor:
- surrounds the carotid artery or has spread to the muscle that opens the jaw, the bone attached to the muscles that move the jaw, nasopharynx, or base of the skull. Cancer may have spread to one or more lymph nodes which can be any size; or
- may be any size and has spread to one or more lymph nodes that are larger than 6 centimeters.
In stage IVC, the tumor may be any size and has spread beyond the oropharynx to other parts of the body, such as the lung, bone, or liver.

Recurrent Oropharyngeal Cancer

Recurrent oropharyngeal cancer is cancer that has recurred (come back) after it has been treated. The cancer may come back in the oropharynx or in other parts of the body.

Treatment Option Overview

Key Points for This Section

There are different types of treatment for patients with oropharyngeal cancer.
Patients with oropharyngeal cancer should have their treatment planned by a team of doctors with expertise in treating head and neck cancer.
Three types of standard treatment are used:
New types of treatment are being tested in clinical trials.
- Radiosensitizers
- Hyperthermia therapy
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 oropharyngeal cancer.

Different types of treatment are available for patients with oropharyngeal 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.

Patients with oropharyngeal cancer should have their treatment planned by a team of doctors with expertise in treating head and neck cancer.

The patient's treatment will be overseen by a medical oncologist, a doctor who specializes in treating people with cancer. Because the oropharynx helps in breathing, eating, and talking, patients may need special help adjusting to the side effects of the cancer and its treatment. The medical oncologist may refer the patient to other health professionals with special training in the treatment of patients with head and neck cancer. These may include the following specialists:

Three types of standard treatment are used:

Surgery

Surgery (removing the cancer in an operation) is a common treatment of all stages of oropharyngeal cancer. A doctor may remove the cancer and some of the healthy tissue around the cancer. Even if the doctor removes all the cancer that can be seen at the time of the surgery, some patients may be given chemotherapy or radiation therapy after surgery to kill any cancer cells that are left. Treatment given after the surgery, to lower the risk that the cancer will come back, is called adjuvant therapy.

Radiation 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. Fractionated radiation therapy divides the total dose of radiation therapy into several smaller, equal doses given over several days.

Radiation therapy may be more effective in patients who have stopped smoking before beginning treatment.

Radiation therapy to the thyroid or pituitary gland increases the risk of hypothyroidism (too little thyroid hormone). Thyroid function tests should be done before and after treatment.

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 cerebrospinal fluid, 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.

See Drugs Approved for Head and Neck Cancer ⁴ for more information. (Oropharyngeal cancer is a type of head and neck cancer.)

New types of treatment are being tested in clinical trials.

This summary section describes treatments that are being studied in clinical trials. It may not mention every new treatment being studied. Information about clinical trials is available from the NCI Web site ⁵.

Radiosensitizers

Radiosensitizers are drugs that make tumor cells more sensitive to radiation therapy. Combining radiation therapy with radiosensitizers may kill more tumor cells.

Hyperthermia therapy

Hyperthermia therapy is a treatment in which body tissue is exposed to increased temperature to damage and kill cancer cells or to make cancer cells more sensitive to the effects of radiation and certain anticancer drugs.

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 listing of clinical trials.

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.

After treatment for oropharyngeal cancer, frequent and careful follow-up is important because of the risk of developing a second cancer in the head or neck.

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.

Stage I Oropharyngeal Cancer

Treatment of stage I oropharyngeal cancer may include the following:

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage I oropharyngeal 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 ⁷.

Stage II Oropharyngeal Cancer

Treatment of stage II oropharyngeal cancer may include the following:

Radiation therapy (external radiation therapy and/or internal radiation therapy).
Surgery.

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage II oropharyngeal cancer ⁸. 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 ⁷.

Stage III Oropharyngeal Cancer

Treatment of stage III oropharyngeal cancer may include the following:

Surgery followed by radiation therapy or by chemotherapy given at the same time as radiation therapy.
Radiation therapy (for patients with tongue or tonsil cancer).
Chemotherapy given at the same time as radiation therapy.
A clinical trial of chemotherapy followed by surgery or radiation therapy.
A clinical trial of chemotherapy given at the same time as radiation therapy.
A clinical trial of fractionated and/or internal radiation therapy.

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage III oropharyngeal cancer ⁹. 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 ⁷.

Stage IV Oropharyngeal Cancer

Treatment of stage IV oropharyngeal cancer that can be treated by surgery may include the following:

Surgery followed by radiation therapy and chemotherapy.
Radiation therapy (for tonsil cancer).
A clinical trial of chemotherapy given at the same time as radiation therapy.
A clinical trial of fractionated and/or internal radiation therapy.

Treatment of stage IV oropharyngeal cancer that cannot be treated by surgery may include the following:

Radiation therapy with or without chemotherapy.
A clinical trial of chemotherapy with radiation therapy and/or radiosensitization.
A clinical trial of fractionated and/or internal radiation therapy.
A clinical trial of radiation therapy with or without chemotherapy.
A clinical trial of hyperthermia therapy with radiation therapy.

Following treatment, it is important to have careful head and neck examinations to look for recurrence. Check-ups will be done monthly in the first year, every 2 months in the second year, every 3 months in the third year, and every 6 months thereafter.

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage IV oropharyngeal cancer ¹⁰. 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 ⁷.

Treatment Options for Recurrent Oropharyngeal Cancer

Treatment of recurrent oropharyngeal cancer may include the following:

Surgery if radiation therapy did not remove all the cancer.
Radiation therapy (if not previously used) or additional surgery if the first surgery did not remove all the cancer.
A clinical trial of chemotherapy.
A clinical trial of hyperthermia therapy with radiation therapy.

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with recurrent oropharyngeal cancer ¹¹. 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 ⁷.

To Learn More About Oropharyngeal Cancer

For more information from the National Cancer Institute about oropharyngeal cancer, see the following:

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

Changes to This Summary (04/24/2012)

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.

Images were added to this summary.

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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 ³⁰. 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.

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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.

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Glossary Terms

abnormal (ab-NOR-mul)

Not normal. An abnormal lesion or growth may be cancer, premalignant (likely to become cancer), or benign (not cancer).

alcohol (AL-kuh-hol)

A chemical substance found in beer, wine, and liquor, and some medicines, mouthwashes, household products, and essential oils (scented liquid taken from plants). Alcohol contains a carbon atom attached to a hydroxyl group (a molecule made of an oxygen atom and a hydrogen atom).

biopsy (BY-op-see)

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

cancer (KAN-ser)

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 a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a 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. Also called malignancy.

cell (sel)

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

clinical trial (KLIH-nih-kul TRY-ul)

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.

CT scan (… skan)

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.

diet (DY-et)

The things a person eats and drinks.

endoscope (EN-doh-SKOPE)

A thin, tube-like instrument used to look at tissues inside the body. An endoscope has a light and a lens for viewing and may have a tool to remove tissue.

endoscopy (en-DOS-koh-pee)

A procedure that uses an endoscope to examine the inside of the body. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.

esophagus (ee-SAH-fuh-gus)

The muscular tube through which food passes from the throat to the stomach.

glucose (GLOO-kose)

A type of sugar; the chief source of energy for living organisms.

grade (grayd)

A description of a tumor based on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. Grading systems are different for each type of cancer.

head and neck cancer (... KAN-ser)

Cancer that arises in the head or neck region (in the nasal cavity, sinuses, lips, mouth, salivary glands, throat, or larynx [voice box]).

human papillomavirus (HYOO-mun PA-pih-LOH-muh-VY-rus)

A type of virus that can cause abnormal tissue growth (for example, warts) and other changes to cells. Infection for a long time with certain types of human papillomavirus can cause cervical cancer. Human papillomavirus may also play a role in some other types of cancer, such as anal, vaginal, vulvar, penile, oropharyngeal, and squamous cell skin cancers. Also called HPV.

infection (in-FEK-shun)

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

injection (in-JEK-shun)

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

lymph node (limf node)

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.

malignant (muh-LIG-nunt)

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

MRI

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.

National Cancer Institute (NA-shuh-nul KAN-ser IN-stih-TOOT)

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.

organ (OR-gun)

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

oropharyngeal cancer (OR-oh-fuh-RIN-jee-ul KAN-ser)

Cancer that forms in tissues of the oropharynx (the part of the throat at the back of the mouth, including the soft palate, the base of the tongue, and the tonsils). Most oropharyngeal cancers are squamous cell carcinomas (cancer that begins in flat cells lining the oropharynx).

oropharynx (OR-oh-FAYR-inx)

The part of the throat at the back of the mouth behind the oral cavity. It includes the back third of the tongue, the soft palate, the side and back walls of the throat, and the tonsils.

pathologist (puh-THAH-loh-jist)

A doctor who identifies diseases by studying cells and tissues under a microscope.

PET scan (… skan)

A procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is used. Because cancer cells often use more glucose than normal cells, the pictures can be used to find cancer cells in the body. Also called positron emission tomography scan.

pharynx (FAYR-inx)

The hollow tube inside the neck that starts behind the nose and ends at the top of the trachea (windpipe) and esophagus (the tube that goes to the stomach). The pharynx is about 5 inches long, depending on body size. Also called throat.

physical examination (FIH-zih-kul eg-ZA-mih-NAY-shun)

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

prognosis (prog-NO-sis)

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

radionuclide (RAY-dee-oh-NOO-klide)

An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radionuclides may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment. Also called radioisotope.

recurrent cancer (ree-KER-ent KAN-ser)

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.

risk factor (... FAK-ter)

Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.

scanner (SKA-ner)

In medicine, an instrument that takes pictures of the inside of the body.

soft palate (... PAL-et)

The back, muscular (not bony) part of the roof of the mouth.

squamous cell (SKWAY-mus sel)

Flat cell that looks like a fish scale under a microscope. These cells cover inside and outside surfaces of the body. They are found in the tissues that form the surface of the skin, the lining of the hollow organs of the body (such as the bladder, kidney, and uterus), and the passages of the respiratory and digestive tracts.

squamous cell carcinoma (SKWAY-mus sel KAR-sih-NOH-muh)

Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts. Also called epidermoid carcinoma.

stage (stayj)

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.

stimulant (STIM-yoo-lunt)

In medicine, a family of drugs used to treat depression, attention-deficit disorder (a common disorder in which children are inattentive, impulsive, and/or over-active), and narcolepsy (a sleep disorder that causes uncontrollable sleepiness). Stimulants increase brain activity, alertness, attention, and energy. They also raise blood pressure and increase heart rate and breathing rate.

stomach (STUH-muk)

An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.

symptom (SIMP-tum)

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

tissue (TIH-shoo)

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

tobacco (tuh-BA-koh)

A plant with leaves that have high levels of the addictive chemical nicotine. The leaves may be smoked (in cigarettes, cigars, and pipes), applied to the gums (as dipping and chewing tobacco), or inhaled (as snuff). Tobacco leaves also contain many cancer-causing chemicals, and tobacco use and exposure to secondhand tobacco smoke have been linked to many types of cancer and other diseases. The scientific name is Nicotiana tabacum.

tonsil (TON-sil)

One of two small masses of lymphoid tissue on either side of the throat.

trachea (TRAY-kee-uh)

The airway that leads from the larynx (voice box) to the bronchi (large airways that lead to the lungs). Also called windpipe.

tumor (TOO-mer)

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.

vein (vayn)

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

x-ray (EX-ray)

A type of radiation used in the diagnosis and treatment of cancer and other diseases. 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.

Table of Links
¹	http://www.cancer.gov/PublishedContent/MediaLinks/297447.html
²	http://www.cancer.gov/cancertopics/pdq/treatment/oropharyngeal/Patient/#Section _14
³	http://www.cancer.gov/PublishedContent/MediaLinks/297448.html
⁴	http://www.cancer.gov/cancertopics/druginfo/head-and-neck-cancer
⁵	http://cancer.gov/clinicaltrials
⁶	http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=40133&tt=1&a mp;format=1&cn=1
⁷	http://www.cancer.gov/clinicaltrials
⁸	http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=40135&tt=1&a mp;format=1&cn=1
⁹	http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=40136&tt=1&a mp;format=1&cn=1
¹⁰	http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=40137&tt=1&a mp;format=1&cn=1
¹¹	http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=40138&tt=1&a mp;format=1&cn=1
¹²	http://www.cancer.gov/cancertopics/types/head-and-neck
¹³	http://www.cancer.gov/cancertopics/types/throat
¹⁴	http://www.cancer.gov/cancertopics/wyntk/oral
¹⁵	http://www.cancer.gov/cancertopics/pdq/prevention/oral/Patient
¹⁶	http://www.cancer.gov/cancertopics/pdq/screening/oral/Patient
¹⁷	http://www.cancer.gov/cancertopics/pdq/supportivecare/oralcomplications/Patient
¹⁸	http://www.cancer.gov/cancertopics/factsheet/Sites-Types/head-and-neck
¹⁹	http://www.cancer.gov/cancertopics/smoking
²⁰	http://www.cancer.gov/cancertopics/wyntk/overview
²¹	http://www.cancer.gov/cancertopics/understandingcancer/cancer
²²	http://www.cancer.gov/cancertopics/factsheet/Detection/staging
²³	http://www.cancer.gov/cancertopics/chemotherapy-and-you
²⁴	http://www.cancer.gov/cancertopics/radiation-therapy-and-you
²⁵	http://www.cancer.gov/cancertopics/coping
²⁶	http://www.cancer.gov/cancertopics/cancerlibrary/questions
²⁷	http://www.cancer.gov/cancertopics/cancerlibrary
²⁸	http://dccps.cancer.gov/ocs/resources.html
²⁹	https://livehelp.cancer.gov
³⁰	http://cancer.gov
³¹	https://pubs.cancer.gov/ncipl