What are cancers of the lip, mouth and oropharynx?

This section covers cancers on the lips and inside the mouth – the oral cavity. The mouth includes many structures:

• Lips
• Tongue
• Gums or gingiva
• Inner lining of the lips and cheeks called the buccal mucosa
• Area of the mouth under the tongue – floor of the mouth
• Roof of the mouth – the hard palate
• The area of the mouth behind the wisdom teeth – retromolar trigone
• Oropharynx – this is the first part of the throat at the back of the mouth, it is made up of:
  • The back of the tongue
  • The tonsils
  • The back wall of the throat
  • The soft palate which is a continuation of the hard palate.

Any of these areas may be affected by mouth cancer. Refer to the labelled diagram below.

A cross section of the head showing nasal cavity, maxilla (bone), hard palate, soft palate, tongue, gums, teeth, buccal mucosa, oropharynx. Credit: Miles Kelly Art Library, Wellcome Images.

The majority - around 90% - of cancers of the lip, mouth and oropharynx are squamous cell cancers. Rarer types of cancer affecting the mouth include salivary gland carcinoma, lymphoma and melanoma. These rare types are not covered by this guidance.

This sort of cancer is uncommon in people under 50 and is more common in men. There are several well recognised risk factors including smoking, drinking, and chewing tobacco or betel nut. The risks are higher for someone who both smokes and drinks. Mouth cancer has started to affect younger people who do not smoke or drink excessively – these mouth cancers are thought to be associated with Human Papilloma Virus (HPV) infection.

These cancers are more common in people who are immunosuppressed either because they are taking immunosuppressant drugs or because they have AIDS. There are two conditions of the mouth that are precancerous; they are called leukoplakia and erythroplakia. They are not cancer of the mouth in themselves, but can develop into cancer if not treated. Life long treatment and follow up is required.

5,300 people develop lip, mouth and oropharyngeal cancer each year in the UK. The five year survival is just over 50%. Results for people with lip cancer are much better at around 90%; this is because changes in the lip are noticed early compared to changes inside the mouth.

Amended November 2008