Oral cancer

It isn’t easy to spot

Your dentist is also trained to spot signs of oral cancer – that is, cancer of the lips, gums, tongue and inside of the mouth. Oral cancer checks are now routinely included in your dental checkup. To do a proper assessment, your dentist must ask about your medical history and conduct an oral cancer exam. If your dentist detects a suspicious lesion, he or she may take a biopsy and refer you to a specialist. About 80 percent of oral cancer patients survive when the disease is detected early.

What is oral cancer?

Oral cancer refers to all cancers of the oral cavity, which includes the following:

  • lips
  • tongue
  • teeth
  • gums (gingiva)
  • lining inside the lips and cheeks (labial mucosa and buccal mucosa),
  • floor of the mouth
  • roof of the mouth (palate)
  • the area behind the wisdom teeth

Most oral cancers are located on the sides of the tongue, floor of the mouth and lips.

Incidence and survival rates

Oral cancer represents approximately 2.3 percent of all cancers in Canada. In 2002, these cancers accounted for more than 3,000 new cases and 1,000 deaths.* The five-year survival rate for oral cancer is low, just below 50 percent. However, early detection results in the survival rate increasing sharply to 80 percent.

What are the key risk factors?

  • Smoking – particularly if combined with heavy alcohol consumption. About 90 percent of people with oral cancer use tobacco. However, quitting tobacco and alcohol significantly lowers the risk of developing oral cancer, even after many years of use
  • Chewing tobacco or snuff
  • Heavy alcohol consumption, particularly if combined with smoking
  • Excessive sun exposure to the lips, often through working in outdoor jobs like construction
  • Age – oral cancer is more common in people over 50
  • Gender – more men than women develop oral cancer


  • A sore on the lip or in the mouth that does not heal.
  • A lump on the lip or in the mouth or throat.
  • A white or red patch on the gums, tongue or lining of the mouth.
  • Unusual bleeding, pain or numbness in the mouth.
  • A sore throat that does not go away, or a feeling that something is caught in the throat.
  • Difficulty or pain with chewing or swallowing.
  • Swelling of the jaw that causes dentures to fit poorly or become uncomfortable.
  • A change in the voice and/or pain in the ear.


A complete medical history is required before conducting an oral cancer assessment either as a routine exam or in cases where oral cancer may be suspected. Any lesion that your dentist determines is unlikely to be cancerous should be observed for seven
to 14 days to ensure that the healing process is ongoing. If the lesion persists, it may be treated non-surgically with:

  • Antibiotics
  • Lavage (i.e., rinsing with water or a medicinal rinse)
  • Lining or repair of sharp or failing restoratives or prosthetics, and
  • Elimination of external factors such as smoking and tobacco chewing

The lesion should be observed for another seven to 14 days, again to assess healing.
When there is a high suspicion of cancer, an immediate biopsy will be needed to determine if the lesion is cancerous. In these cases, waiting for seven to 14 days is not advised. Depending on the degree of difficulty, your dentist may decide to remove the tissue in office or refer you to a specialist. Lab tests may also be done before or with the biopsy to help determine a diagnosis. These could include:

  • Blood tests
  • Culture and sensitivity
  • Glucose tolerance tests for diabetes mellitus
  • Skin tests for allergy
  • Radiographic surveys
  • Dietary tests

Information courtesy of the Ontario Dental Association.