Introduction

Head and neck cancers constitute a broad spectrum of disease processes with varying histology, natural history, and treatment outcomes. In this chapter we discuss squamous cell cancers of the oral cavity, pharynx, and larynx constituting about 80% of head and neck malignancies. The annual incidence of such cancers is approximately 45 000 cases per year in the US. This is the fifth most common cancer in the world today. Median age at presentation is 60 years and two-thirds of patients are men. There is a strong association with alcohol and/or tobacco use, and most patients present with local or regionally advanced disease.

There exists a dose–response relationship between exposure to tobacco and cancers of the head and neck. Smoking is the preferred method of tobacco use in the United States, and is most strongly associated with malignancies of the floor of mouth, oropharynx, and larynx., Other practices, for example chewing tobacco or dipping snuff, tend to be associated with malignancies of the buccal mucosa., Alcohol use is an independent risk factor and there appear to be synergistic carcinogenic effects for persons who both smoke and drink, especially for cancers of the larynx. There is an inverse relationship between the consumption of fruits and vegetables and head and neck squamous cell cancers. Viral exposures have also been implicated in the causation of some uncommon head and neck malignancies. In the Orient, there is a clear etiologic relationship between Epstein–Barr virus and nasopharyngeal carcinoma.