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Oral cancer

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Precancerous conditions of the oral cavity

Precancerous conditions of the oral cavity have the potential to develop into oral cavity cancer. When cells that line the oral cavity are exposed to carcinogens, such as cigarette smoke, they can change and become more likely to develop into cancer (this process is known as field cancerization). The affected area may have visible precancerous lesions (abnormal areas), but precancerous conditions are often not apparent. As a result, precancerous or cancerous conditions may appear later, even after abnormal areas are treated.

The most common precancerous conditions of the oral cavity are:

  • leukoplakia
  • erythroplakia
  • erythroleukoplakia
  • proliferative verrucous leukoplakia (PVL)
  • oral submucous fibrosis

Leukoplakia

Leukoplakia is an abnormal white area or spots on the mucous membrane lining the mouth with no clear cause. There are many conditions that present with white areas, such as thrush and lichen planus. White spots may also be caused by irritation, such as biting the cheek or lip.

The presence of leukoplakia does not necessarily mean cancer. About 3%–17.5% of people develop squamous cell carcinoma in an area of leukoplakia within 15 years of developing leukoplakia.

The actual risk of developing oral cavity cancer depends on how abnormal the cells lining the mouth are in shape, size and appearance. This abnormality is called dysplasia. People who have leukoplakia are closely followed to look for signs of cancer.

Risks factors

The following risk factors may increase a person’s chance of developing leukoplakia:

  • heavy smoking and excessive alcohol use
  • chewing tobacco (snuff)

Signs and symptoms

The signs and symptoms of leukoplakia may include a whitish area or spots inside the mouth that cannot be easily scraped off.

Diagnosis

If the signs and symptoms of leukoplakia are present, the doctor will do an oral examination and order tests to make a diagnosis and rule out other conditions that can cause similar lesions. Tests may include taking a sample of cells from the abnormal area and examining them under a microscope (biopsy). Doctors may do a biopsy of any suspicious area, especially in people at high-risk of developing cancer, such as those who use tobacco products.

Treatment

There are no standard treatments for leukoplakia. It is managed by active surveillance, which involves closely monitoring a person’s condition. Tests and exams are done on a regular schedule to detect any cancerous change early.

Because leukoplakia has the potential to develop into cancer, people with this condition should avoid known risk factors, such as tobacco and alcohol.

Erythroplakia

Erythroplakia is an abnormal red area or red spots that form on the mucous membrane lining the mouth with no clear cause. The presence of erythroplakia does not necessarily mean cancer, but this precancerous condition has the highest risk of developing into cancer. About 51% of these lesions develop into squamous cell carcinoma and 40% develop into carcinoma in situcarcinoma in situA very early stage of cancer in which tumour cells have not yet invaded surrounding tissues..

Risks factors

The following risk factors may increase a person’s chance of developing erythroplakia:

  • heavy smoking and excessive alcohol use
  • chewing tobacco

Signs and symptoms

The signs and symptoms of erythroplakia may include a raised, velvety, red area that often bleeds when scraped.

Diagnosis

If the signs and symptoms of erythroplakia are present, the doctor will do an oral examination and run tests to make a diagnosis and rule out other conditions that can cause similar lesions. Tests may include taking a sample of cells from the abnormal area and examining them under a microscope (biopsy). Doctors may do a biopsy of any suspicious area, especially in people at high-risk of developing cancer, such as those who use tobacco products.

Treatment

Treatment options for erythroplakia may include:

  • careful watching (surveillance) and frequent follow-up
  • surgical removal
  • cryosurgery and laser surgery – uncommon

Because erythroplakia has the potential to develop into cancer, people with this condition should avoid known risk factors, such as tobacco and alcohol.

Erythroleukoplakia

Erythroleukoplakia is a mix of white and red areas on the mucous membrane lining the oral cavity with no clear cause. Other diseases that cause similar lesions are ruled out. This precancerous condition is also called speckled leukoplakia or speckled erythroplakia. The risk of oral cavity cancer developing from erythroleukoplakia falls between the risk for leukoplakia and erythroplakia.

Proliferative verrucous leukoplakia (PVL)

This is an aggressive form of oral leukoplakia. It is seen more often in older women and is not strongly linked to tobacco use. People with PVL develop multiple lesions that do not go away and have a high risk of developing into cancer. Up to 87% of cases develop into cancer. Because it is so aggressive, PVL requires close follow-up. If cancer develops, then early and aggressive treatment is given. It often recurs or is resistant to treatment.

Oral submucous fibrosis

Oral submucous fibrosis is a condition that causes progressive fibrosis (formation of scar-like tissue) in the lining of the mouth. It is strongly linked to chewing betel nut (paan). The chance of developing oral cavity cancers in people with oral submucous fibrosis is 7%–13%.

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