Causes
Oral cancer is not caused by one thing, but certain factors increase its risk. Factors include smoking, chewing tobacco or using snuff, drinking excessive alcohol, having unprotected sun exposure to the lips, and chewing betel nut - all these increase the risk of developing oral cancer. This risk of oral cancer is even higher when people have more than one or all of these unhealthy habits.
Infections of the mouth with the human papillomavirus (HPV) may also increase the risk of oral cancer. For some, oral cancer develops without any of these risks. People that have had head and neck cancer in the past may also have an increased risk of oral cancer.