Oral and pharyngeal cancers.

Trends for oral and pharyngeal cancers vary by anatomical subsite. For tumours of the tongue, mouth and pharynx (excluding nasopharynx), rates are rising in many areas of the world, particularly in Europe, at least in part attributable to rising alcohol consumption. Exceptions to this pattern occur in the USA, where incidence and mortality among whites are falling. There are mild downward trends in the incidence of lip, salivary gland and nasopharyngeal cancers, which (except for nasopharyngeal cancer among southern Chinese) occur at much lower frequency. The trends provide interesting clues to the causes of these cancers whose aetiology is partially but not fully understood.