Head and Neck Tumors

Abstract

In the United States, head and neck cancers account for 3.0% (39,400) of all new cancers and 2.0% (11,200) of cancer deaths.1 The disease is more common in many developing countries. The incidence of head and neck cancer increases with age; most patients are older than age 50. The male-to-female ratio is approximately 3:1, and the African-American population has experienced a significant increase.2 The greatest risk factor is tobacco use. It has been shown that heavy smokers have a five-to 25-fold higher risk of head and neck cancer than nonsmokers. The use of smokeless tobacco is strongly associated with the formation of premalignant oral lesions (hyperkeratosis, epithelial dysplasia), at rates ranging from 16% to 60%.3 Dietary factors seem to play a role in the risk of oral and pharyngeal cancers. Epidemiologic studies have shown an increased risk of cancer in individuals whose diets lack sufficient quantities of nutrients. Mutagen sensitivity has been shown to be a strong independent risk factor for the development of head and neck cancer and seems to have a multiplicative interaction with smoking. Epstein-Barr virus (EBV) is associated with nasopharyngeal carcinoma (NPC). The EBV viral genome has been found in NPC tissue. Most patients with NPC show evidence of an elevated serum titer of immunoglobulin G (IgG) and IgA antibodies against viral capsid antigen.4 The association of NPC and EBV is particularly strong in patients with endemic undifferentiated carcinoma.5 Human papilloma virus, especially types 16 and 18, and herpes simplex virus type I have been detected in the sera and tumor tissues of patients with head and neck cancer.6