Tobacco (including smokeless tobacco) and alcohol use are the most important risk factors for oral, head and neck cancers, particularly those of the tongue, mouth, throat and voice box. Eighty-five percent of head and neck cancers are linked to tobacco use. People who use both tobacco and alcohol are at greater risk for developing these cancers than people who use either tobacco or alcohol alone. (Source: National Cancer Institute).
Anyone can develop thyroid cancers, although a family history or exposure to radiation is often a factor. Salivary gland cancers do not seem to be associated with any particular cause.