Symptoms and causes


Signs and symptoms of mouth cancer may include:

  • A sore that doesn't heal
  • A lump or thickening of the skin or lining of your mouth
  • A white or reddish patch on the inside of your mouth
  • Loose teeth
  • Poorly fitting dentures
  • Tongue pain
  • Jaw pain or stiffness
  • Difficult or painful chewing
  • Difficult or painful swallowing
  • Sore throat

When to see a doctor

Make an appointment with your doctor or dentist if you have any persistent signs and symptoms that bother you and last more than two weeks. Your doctor will likely investigate other more common causes for your signs and symptoms first, such as an infection.


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.

Risk factors

Factors that can increase your risk of mouth cancer include:

  • Tobacco use of any kind, including cigarettes, cigars, pipes, chewing tobacco and snuff, among others
  • Heavy alcohol use
  • Excessive sun exposure to your lips
  • A sexually transmitted virus called human papillomavirus (HPV)
Nov. 17, 2015
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