Oral cancer causes

Causes
Oral cancer most commonly involves the tissue of the lips or the tongue. It may also occur on the floor of the mouth, cheek lining, gums (gingiva), or roof of the mouth (palate).

Most oral cancers look very similar under the microscope and are called squamous cell carcinomas. These are malignant and tend to spread rapidly.

Smoking and other tobacco use are associated with 70 - 80% of oral cancer cases. Smoke and heat from cigarettes, cigars, and pipes irritate the mucous membranes of the mouth. Use of chewing tobacco or snuff causes irritation from direct contact with the mucous membranes. Heavy alcohol use is another activity associated with increased risk for oral cancer.

Other factors that increase the risk of oral cancer include poor dental and oral hygiene and chronic irritation (such as from rough teeth, dentures, or fillings). Some oral cancers begin as a white plaque (leukoplakia) or as a mouth ulcer. Recently, infection with HPV (human papilloma virus) has beeen shown to be a risk factor.

Oral cancer accounts for about 8% of all malignant growths. Men get oral cancer twice as often as women do, particularly men older than 40.