Mouth cancer occurs when cells on your lips or in your mouth develop changes (mutations) in their DNA. These mutations allow cancer cells to grow and divide when healthy cells would die. The accumulating mouth cancer cells can form a tumor. With time they may spread to other areas of the mouth and on to other areas of the head and neck or other parts of the body.

Mouth cancers most commonly begin in the flat, thin cells (squamous cells) that line your lips and the inside of your mouth. Most oral cancers are squamous cell carcinomas.

It's not clear what causes the mutations in squamous cells that lead to mouth cancer. But doctors have identified factors that may increase the risk of mouth cancer.

Types of mouth cancer

Mouth cancer is a general term that applies to cancers that occur on the lips and throughout the mouth. More-specific terms for these types of cancer include:

  • Cancer that affects in the inside portion of the cheeks (buccal mucosa cancer)
  • Floor of mouth cancer
  • Gum cancer
  • Lip cancer
  • Roof of mouth (hard palate) cancer
  • Salivary gland cancer
  • Tongue cancer
Nov. 02, 2012