Oral cancer is a type of head and neck cancer that occurs in the mouth or lips, and is most often a squamous cell carcinoma.
Oral cancer: find out more
Oral cancer, or mouth cancer, is cancer that develops in any of the parts of the oral cavity:
- Inner lining of the cheeks
- Roof of the mouth
- Floor of the mouth under the tongue
We still don’t know the exact cause, but oral cancer develops when cells from the lips or in the mouth develop mutations in their DNA and grow out of control. These abnormal mouth cancer cells can form a tumor and may spread inside the mouth and to other areas of the head and neck, or other parts of the body.
Mouth cancers most commonly begin in the flat, thin squamous cells that line your lips and the inside of your mouth, so most oral cancers are squamous cell carcinomas.
Types of oral cancer
Squamous cell carcinomas. More than 90% of oral cancers. The earliest form of squamous cell cancer is called carcinoma in situ, meaning that the cancer cells are only in the layer of cells called the epithelium. This is different from invasive squamous cell carcinoma, where the cancer cells have grown into deeper layers of the oral cavity.
Verrucous carcinoma. Less than 5% of all oral cancers. A low-grade or slow growing cancer that rarely spreads to other parts of the body, but it can grow deeply into nearby tissue.
Minor salivary gland carcinomas. Can start in the glands in the lining of the mouth and throat. There are many types of minor salivary gland cancers, including adenoid cystic carcinoma, mucoepidermoid carcinoma, and polymorphous low-grade adenocarcinoma.
Lymphomas. The tonsils and base of the tongue contain immune system tissue, or lymphoid tissue, where lymphomas can start.