What is cancer of the lip and oral cavity?

Cancer of the lip and oral cavity is a disease in which malignant (cancerous) cells form on the lips or the mouth. The oral cavity includes the front two-thirds of the tongue, the gums, the lining of the inside of the cheeks, the bottom of the mouth under the tongue, the roof of the mouth, and the small area behind the wisdom teeth. The main cause of these cancers is tobacco use, both smoking and smokeless (chewing) tobacco. Heavy alcohol use also increases risk, especially if combined with tobacco use. Other risk factors include ultraviolet light (from sunlight or tanning beds) and infection with the human papillomavirus (HPV). Men are more likely to get cancers of the lip and oral cavity than women, partly because more men than women smoke. These cancers usually start in the thin flat cells that line the lips and oral cavity, called squamous cells, and often show up as white patches that do not rub off. They can spread into deeper tissue. A dental checkup can identify early signs of cancer of the lip and oral cavity. Early detection greatly increases the chances of successful treatment and survival.