Every year, roughly 40,000 Americans and 350,000 people worldwide are diagnosed with oral cancer for the first time. In the general population, oral cancer is the sixth most frequent disease for both men and women, and the third most common cancer in developing countries. About half of those affected will die within five years of being diagnosed, while those who survive will likely have significant cosmetic and/or functional problems. Oral cancer is defined as cancer of the oral cavity and pharynx, which includes cancers of the lip, tongue, salivary glands, gum, floor, and other regions of the mouth, oropharynx, nasopharynx, hypopharynx, pharynx, and other buccal areas, according to the International Classification of Diseases. Carcinomas account for 96 percent of all oral malignancies, with squamous cell carcinomas accounting for 91 percent.