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Oral Cancer Screening (PDQ®)
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Table of Contents

What is screening?
General Information About Oral Cancer
Oral Cancer Screening
Risks of Oral Cancer Screening
Get More Information From NCI
Changes to This Summary (08/27/2008)
Questions or Comments About This Summary
About PDQ

What is screening?

Screening is looking for cancer before a person has any symptoms. This can help find cancer at an early stage. When abnormal tissue or cancer is found early, it may be easier to treat. By the time symptoms appear, cancer may have begun to spread.

Scientists are trying to better understand which people are more likely to get certain types of cancer. They also study the things we do and the things around us to see if they cause cancer. This information helps doctors recommend who should be screened for cancer, which screening tests should be used, and how often the tests should be done.

It is important to remember that your doctor does not necessarily think you have cancer if he or she suggests a screening test. Screening tests are given when you have no cancer symptoms.

If a screening test result is abnormal, you may need to have more tests done to find out if you have cancer. These are called diagnostic tests.

See the following PDQ summaries for information about prevention, diagnosis, and treatment of oral cancer.

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General Information About Oral Cancer

Key Points for This Section


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.

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.

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Oral Cancer Screening

Key Points for This Section


Tests are used to screen for different types of cancer.

Some screening tests are used because they have been shown to be helpful both in finding cancers early and in decreasing the chance of dying from these cancers. Other tests are used because they have been shown to find cancer in some people; however, it has not been proven in clinical trials that use of these tests will decrease the risk of dying from cancer.

Scientists study screening tests to find those with the fewest risks and most benefits. Cancer screening trials also are meant to show whether early detection (finding cancer before it causes symptoms) decreases a person's chance of dying from the disease. For some types of cancer, the chance of recovery is better if the disease is found and treated at an early stage.

Clinical trials that study cancer screening methods are taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI Web site.

There is no standard or routine screening test for oral cancer.

Screening for oral cancer may be done during a routine check-up by a dentist or doctor. The exam will include looking for lesions, including areas of 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 cancerous. Higher-risk areas of the mouth that are checked for cancer include the following:

  • Floor of the mouth.
  • Front and sides of the tongue.
  • Soft palate.

If lesions are seen in the mouth, the following procedures may be used to find abnormal tissue that might develop into oral cancer:

  • Toluidine blue stain: A procedure in which lesions in the mouth are coated with a blue dye. Areas that stain darker are more likely to be cancer or become cancer.
  • Fluorescence staining: A procedure in which lesions in the mouth are viewed using a special light. After the patient uses a fluorescent mouth rinse, normal tissue looks different from abnormal tissue when seen under the light.
  • Exfoliative cytology: A procedure to collect cells from the lip or oral cavity. A piece of cotton, a brush, or a small wooden stick is used to gently scrape cells from the lips, tongue, mouth, or throat. The cells are viewed under a microscope to find out if they are abnormal.
  • Brush biopsy: The removal of cells using a brush that is designed to collect cells from all layers of a lesion. The cells are viewed under a microscope to find out if they are abnormal.

Early-stage oral cancer can be cured, but most oral cancers have already spread to lymph nodes or other areas by the time they are found. No studies have been done to find out if screening would decrease the risk of dying from this disease.

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Risks of Oral Cancer Screening

Key Points for This Section


Screening tests have risks.

Decisions about screening tests can be difficult. Not all screening tests are helpful and most have risks. Before having any screening test, you may want to discuss the test with your doctor. It is important to know the risks of the test and whether it has been proven to reduce the risk of dying from cancer.

The risks of oral cancer screening include the following:

False-negative test results can occur.

Screening test results may appear to be normal even though oral cancer is present. A person who receives a false-negative test result (one that shows there is no cancer when there really is) may delay seeking medical care even if there are symptoms. Exfoliative cytology has a high number of false-negative results.

False-positive test results can occur.

Screening test results may appear to be abnormal even though no cancer is present. A false-positive test result (one that shows there is cancer when there really isn't) can cause anxiety and is usually followed by more tests and procedures (such as biopsy). which also have risks. Oral exams have a high number of false-positive results.

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Get More Information From NCI

Call 1-800-4-CANCER

For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 a.m. to 4:30 p.m. Deaf and hard-of-hearing callers with TTY equipment may call 1-800-332-8615. The call is free and a trained Cancer Information Specialist is available to answer your questions.

Chat online

The NCI's LiveHelp® online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 9:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.

Write to us

For more information from the NCI, please write to this address:

NCI Public Inquiries Office
Suite 3036A
6116 Executive Boulevard, MSC8322
Bethesda, MD 20892-8322

Search the NCI Web site

The NCI Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use our “Best Bets” search box in the upper right hand corner of each Web page. The results that are most closely related to your search term will be listed as Best Bets at the top of the list of search results.

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. 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.

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Changes to This Summary (08/27/2008)

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.

This summary was completely reformatted and some content was added.

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Questions or Comments About This Summary

If you have questions or comments about this summary, please send them to Cancer.gov through the Web site’s Contact Form. We can respond only to email messages written in English.

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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. 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 a method of finding cancer earlier can help people to live longer. 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 and those who are at risk for cancer. During screening clinical trials, information is collected about the effects of a new screening method and how well it works. If a clinical trial shows that a new method is better than one currently being used, the new method may become "standard." People who are at high risk for a certain type of cancer may want to think about taking part in a clinical trial.

Listings of clinical trials are included in PDQ and are available online at NCI's Web site. 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.

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