ABSTRACT
Head and neck cancers, also known as cancers of the upper aerodigestive tract, are chiefly squamous cell carcinomas arising in the oral cavity, pharynx, or larynx. About 40,000 persons are diagnosed with squamous cell carcinoma of the head and neck (SCCHN) in the United States each year, and about 12,000 die of the disease. This chapter focuses on recent molecular epidemiological studies with an emphasis on the role of DNA repair in susceptibility to SCCHN. Tobacco initiates a linear dose–response carcinogenic effect in which the duration of exposure is more important than the intensity of exposure. While it has been suggested that various infectious agents play a role in head and neck carcinogenesis, only Epstein-Barr virus and human papilloma virus can be implicated as etiological agents in head and neck carcinogenesis based on current scientific evidence. A high-profile legal case in Australia has brought significant interest to the risk of SCCHN secondary to exposure to environmental tobacco smoke.
