Key Points for This Section

Avoiding risk factors and increasing protective factors may help prevent cancer. The following risk factors may increase the risk of oral cancer: Tobacco use Alcohol use Sun exposure HPV infection Marijuana Use The following protective factors may decrease the risk of oral cancer: Dietary factors Chemoprevention Cancer prevention clinical trials are used to study ways to prevent cancer. New ways to prevent oral cancer are being studied in clinical trials.

Avoiding risk factors and increasing protective factors may help prevent cancer.

Avoiding cancer risk factors such as smoking, being overweight, and lack of exercise may help prevent certain cancers. Increasing protective factors such as quitting smoking, eating a healthy diet, and exercising may also help prevent some cancers. Talk to your doctor or other health care professional about how you might lower your risk of cancer.

The following risk factors may increase the risk of oral cancer:

Tobacco use

Using tobacco is the leading cause of oral cancer.

All forms of tobacco, including cigarettes, pipes, cigars, and chewing (smokeless) tobacco, are linked to oral cancer. The risk of oral cancer increases with the number of cigarettes smoked per day. Tobacco use is most likely to cause oral cancer in the floor of the mouth, but also causes cancer in the oral cavity and oropharynx and on the lips.

The risk of oral cancer is greater in people who use both tobacco and alcohol than it is in people who use only tobacco or only alcohol.

Tobacco users who have had oral cancer may develop second cancers in the oral cavity or nearby areas, including the nose, throat, vocal cords, esophagus, and trachea (windpipe).

Results from clinical trials have shown that when a person stops smoking cigarettes, the risk of oral cancer decreases by one-half (50%) within 5 years. Within 10 years of quitting, the risk of oral cancer is the same as for a person who never used tobacco.

Alcohol use

Using alcohol is a major risk factor for oral cancer.

The risk of oral cancer increases with the number of alcoholic drinks consumed per day. Alcohol use is also a risk factor for leukoplakia (an abnormal white patch of cells) and erythroplakia (an abnormal red patch of cells). Leukoplakia and erythroplakia lesions on the mucous membranes may become cancer.

The risk of oral cancer is greater in people who use both alcohol and tobacco than it is in people who use only alcohol or only tobacco.

Results from clinical trials have not shown a decrease in the risk of oral cancer when a person stops drinking alcohol.

Sun exposure

Being exposed to sunlight may increase the risk of lip cancer, which occurs most often on the lower lip. Avoiding the sun and/or using lip balm with sunscreen or using colored lipstick may decrease the risk of lip cancer.

HPV infection

Being infected with a certain type of human papillomavirus (HPV) may increase the risk of oral cancer.

Marijuana Use

Using marijuana may increase the risk of oral cancer. Marijuana use by a person with high-risk HPV infection may further increase the risk of oral cancer.

The following protective factors may decrease the risk of oral cancer:

Dietary factors

Eating a diet high in fruits and fiber -rich vegetables may lower the risk of developing oral cancer.

Chemoprevention

Chemoprevention is the use of drugs, vitamins, or other agents to prevent or delay the growth of cancer.

Studies of chemoprevention are under way in patients at high risk for oral cancer, including those with precancerous oral lesions and those with a history of oral cancer. Check NCI's Cancer Clinical Trials Registry for chemoprevention trials for cancer of the lip and oral cavity ¹ and oropharynx ².

Cancer prevention clinical trials are used to study ways to prevent cancer.

Cancer prevention clinical trials are used to study ways to lower the risk of developing certain types of cancer. Some cancer prevention trials are conducted with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are conducted with people who have had cancer and are trying to prevent another cancer of the same type or to lower their chance of developing a new type of cancer. Other trials are done with healthy volunteers who are not known to have any risk factors for cancer.

The purpose of some cancer prevention clinical trials is to find out whether actions people take can prevent cancer. These may include eating fruits and vegetables, exercising, quitting smoking, or taking certain medicines, vitamins, minerals, or food supplements.

New ways to prevent oral cancer are being studied in clinical trials.

Clinical trials are taking place in many parts of the country. Information about clinical trials can be found in the Clinical Trials section of the NCI Web site ³. Check NCI's PDQ Cancer Clinical Trials Registry for lip and oral cavity cancer prevention trials ⁴ and oropharyngeal cancer prevention trials ⁵ that are now accepting patients.

Glossary Terms

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

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.

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.

The use of drugs, vitamins, or other agents to try to reduce the risk of, or delay the development or recurrence of, cancer.

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.

The things a person eats and drinks.

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.

An abnormal patch of red tissue that forms on mucous membranes in the mouth and may become cancerous. Tobacco (smoking and chewing) and alcohol may increase the risk of erythroplakia.

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

In food, fiber is the part of fruits, vegetables, legumes, and whole grains that cannot be digested. The fiber in food may help prevent cancer. In the body, fiber refers to tissue made of long threadlike cells, such as muscle fiber or nerve fiber.

A member of a family of viruses that can cause abnormal tissue growth (for example, genital warts) and other changes to cells. Infection with certain types of human papillomavirus increases the risk of developing cervical cancer. Also called HPV.

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.

An area of abnormal tissue. A lesion may be benign (noncancerous) or malignant (cancerous).

An abnormal patch of white tissue that forms on mucous membranes in the mouth and other areas of the body. It may become cancerous. Tobacco (smoking and chewing) and alcohol may increase the risk of leukoplakia in the mouth.

A type of plant. Extracts of marijuana are being studied for their ability to control severe nausea and vomiting caused by chemotherapy and/or opioid drugs such as morphine.

Refers to the practices and procedures used for the prevention, treatment, or relief of symptoms of a diseases or abnormal conditions. This term may also refer to a legal drug used for the same purpose.

A nutrient required to maintain health.

The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach). Glands in the mucous membrane make mucus (a thick, slippery fluid). Also called mucosa.

Cancer that forms in tissues of the lip or mouth. This includes the front two thirds of the tongue, the upper and lower gums, the lining inside the cheeks and lips, the bottom of the mouth under the tongue, the bony top of the mouth, and the small area behind the wisdom teeth.

The mouth.

The part of the throat at the back of the mouth. It includes the soft palate, the base of the tongue, and the tonsils.

Being too heavy for one’s height. Excess body weight can come from fat, muscle, bone, and/or water retention. Being overweight does not always mean being obese.

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.

A term used to describe a condition that may (or is likely to) become cancer. Also called premalignant.

In medicine, action taken to decrease the chance of getting a disease or condition. For example, cancer prevention includes avoiding risk factors (such as smoking, obesity, lack of exercise, and radiation exposure) and increasing protective factors (such as getting regular physical activity, staying at a healthy weight, and having a healthy diet).

Something that may decrease the chance of getting a certain disease. Some examples of protective factors for cancer are getting regular physical activity, staying at a healthy weight, and having a healthy diet.

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 substance that helps protect the skin from the sun's harmful rays. Sunscreens reflect, absorb, and scatter both ultraviolet A and B radiation to provide protection against both types of radiation. Using lotions, creams, or gels that contain sunscreens can help protect the skin from premature aging and damage that may lead to skin cancer.

Adding nutrients to the diet.

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 pharynx.

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.

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

A key nutrient that the body needs in small amounts to grow and stay strong. Examples are vitamins A, C, and E.

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