Key Points for This Section

Salivary gland cancer is a rare disease in which malignant (cancer) cells form in the tissues of the salivary glands. Being exposed to certain types of radiation may increase the risk of salivary cancer. Possible signs of salivary gland cancer include a lump or trouble swallowing. Tests that examine the head, neck, and the inside of the mouth are used to detect (find) and diagnose salivary gland cancer. Certain factors affect treatment options and prognosis (chance of recovery).

Salivary gland cancer is a rare disease in which malignant (cancer) cells form in the tissues of the salivary glands.

The salivary glands make saliva and release it into the mouth. Saliva has enzymes that help digest food and antibodies that help protect against infections of the mouth and throat. There are 3 pairs of major salivary glands:

• Parotid glands: These are the largest salivary glands and are found in front of and just below each ear. Most major salivary gland tumors begin in this gland.
• Sublingual glands: These glands are found under the tongue in the floor of the mouth.
• Submandibular glands: These glands are found below the jawbone.

There are also hundreds of small (minor) salivary glands lining parts of the mouth, nose, and larynx that can be seen only with a microscope. Most small salivary gland tumors begin in the palate (roof of the mouth).

More than half of all salivary gland tumors are benign (not cancerous) and do not spread to other tissues.

Being exposed to certain types of radiation may increase the risk of salivary cancer.

Anything that increases the chance 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. Although the cause of most salivary gland cancers is not known, risk factors include the following:

• Older age.
• Treatment with radiation therapy to the head and neck.
• Being exposed to certain substances at work.

Possible signs of salivary gland cancer include a lump or trouble swallowing.

Salivary gland cancer may not cause any symptoms. It is sometimes found during a regular dental check-up or physical exam. Symptoms caused by salivary gland cancer also may be caused by other conditions. A doctor should be consulted if any of the following problems occur:

• A lump (usually painless) in the area of the ear, cheek, jaw, lip, or inside the mouth.
• Fluid draining from the ear.
• Trouble swallowing or opening the mouth widely.
• Numbness or weakness in the face.
• Pain in the face that does not go away.

Tests that examine the head, neck, and the inside of the mouth are used to detect (find) and diagnose salivary gland cancer.

The following procedures may be used:

• Physical exam and history: An exam of the body to check general signs of health. The head, neck, mouth, and throat will be checked 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.
• 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).
• 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.
• 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.
• 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.
• Endoscopy: A procedure to look at organs and tissues inside the body to check for abnormal areas. For salivary gland cancer, an endoscope is inserted into the mouth to look at the mouth, throat, and larynx. An endoscope is a thin, tube-like instrument with a light and a lens for viewing.
• Fine needle aspiration (FNA) biopsy: The removal of tissue or fluid using a thin needle. A pathologist views the tissue or fluid under a microscope to look for cancer cells.

Because salivary gland cancer can be hard to diagnose, patients should ask to have biopsy samples checked by a pathologist who has experience in diagnosing salivary gland cancer.

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

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

• The stage of the cancer (especially the size of the tumor).
• The type of salivary gland the cancer is in.
• The type of cancer cells (how they look under a microscope).
• The patient's age and general health.

Glossary Terms

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

A type of protein made by plasma cells (a type of white blood cell) in response to an antigen (foreign substance). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Antibodies can work in several ways, depending on the nature of the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen.

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

Tissue removed from the body and examined under a microscope to determine whether disease is present.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can 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 individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

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.

Computed tomography scan. 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 computed tomography scan, computerized tomography, computerized axial tomography scan, and CAT scan.

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

The process of breaking down food into substances the body can use for energy, tissue growth, and repair.

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.

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.

A protein that speeds up chemical reactions in the body.

The removal of tissue or fluid with a thin needle for examination under a microscope. Also called FNA biopsy.

Liquid.

An organ that makes one or more substances, such as hormones, digestive juices, sweat, tears, saliva, or milk. Endocrine glands release the substances directly into the bloodstream. Exocrine glands release the substances into a duct or opening to the inside or outside of the body.

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

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.

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

The area of the throat containing the vocal cords and used for breathing, swallowing, and talking. Also called voice box.

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

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, nuclear magnetic resonance imaging, and NMRI.

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

The roof of the mouth. The front portion is bony (hard palate), and the back portion is muscular (soft palate).

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

Positron emission tomography scan. 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.

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

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

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 radiotherapy and irradiation.

Giving off radiation.

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.

The watery fluid in the mouth made by the salivary glands. Saliva moistens food to help digestion and it helps protect the mouth against infections.

A gland in the mouth that produces saliva.

A rare cancer that forms in tissues of a salivary gland (gland in the mouth that makes saliva). Most salivary gland cancers occur in older people.

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

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

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.

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

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 throat is about 5 inches long, depending on body size. Also called the pharynx.

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 cancerous), or malignant (cancerous). Also called neoplasm.

A procedure in which high-energy sound waves (ultrasound) 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.

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

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.