Key Points for This Section

Oral cancer is a disease in which malignant (cancer) cells form in the lips, oral cavity, or oropharynx. The number of new cases of oral cancer and the number of deaths from oral cancer have been decreasing slowly. Tobacco and alcohol use can affect the risk of developing oral cancer.

Oral cancer is a disease in which malignant (cancer) cells form in the lips, oral cavity, or oropharynx.

Oral cancer may develop in any of the following areas:

• Lips.
• Oral cavity:
  • The front two thirds of the tongue.
  • The gingiva (gums).
  • The buccal mucosa (the lining of the inside of the cheeks).
  • The floor (bottom) of the mouth under the tongue.
  • The hard palate (the front of the roof of the mouth).
  • The retromolar trigone (the small area behind the wisdom teeth).
• Oropharynx:
  • The middle part of the pharynx (throat) behind the mouth.
  • The back one third of the tongue.
  • The soft palate (the back of the roof of the mouth).
  • The side and back walls of the throat.
  • The tonsils.

Most oral cancers start in squamous cells, the thin, flat cells that line the lips, oral cavity, and oropharynx. Cancer that forms in squamous cells is called squamous cell carcinoma.

See the following PDQ summaries for more information about oral cancer:

• Oral Cancer Prevention ¹
• Lip and Oral Cavity Cancer Treatment ²

The number of new cases of oral cancer and the number of deaths from oral cancer have been decreasing slowly.

Most oral cancers occur in people older than 45 years, and more often in blacks than in whites. Even though the total number of new cases and deaths from oral cancer has decreased slowly over the past 20 years, the number of new cases of oral cancer (especially of the tongue) has been increasing in adults younger than 40 years.

Tobacco and alcohol use can affect the risk of developing oral 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. Risk factors for oral cancer include the following:

• Using tobacco products (includes cigarettes, cigars, pipes, and smokeless and chewing tobacco).
• Heavy alcohol use.
• Chewing betel nuts.
• Being infected with a certain type of human papillomavirus (HPV).
• Being exposed to sunlight (lip cancer only).
• Being male.

Glossary Terms

A chemical substance found in beer, wine, and liquor. Alcohol is also found in some medicines, mouthwashes, essential oils (scented liquid taken from plants), and household products.

The inner lining of the cheeks.

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.

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

The tissue of the upper and lower jaws that surrounds the base of the teeth. Also called gums.

The front, bony part of the roof of the mouth.

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 may cause cervical cancer. Human papillomavirus may also play a role in some other types of cancer. Also called HPV.

Cancer that forms in tissues of the oral cavity (the mouth) or the oropharynx (the part of the throat at the back of the mouth).

Refers to the mouth. It includes the lips, the lining inside the cheeks and lips, the front two thirds of the tongue, the upper and lower gums, the floor of the mouth under the tongue, the bony roof of the mouth, and the small area behind the wisdom teeth.

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.

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.

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.

The small area behind the wisdom teeth.

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.

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

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.

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.

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.

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