Head and neck cancer is common in several regions of the world. The primary risk factors associated with head and neck cancer include tobacco use, alcohol consumption, human papillomavirus (HPV) infection (for oropharyngeal cancer), and Epstein-Barr virus (EBV) infection (for nasopharyngeal cancer). The relative prevalence of these risk factors contributes to the variations in the observed distribution of head and neck cancer in different areas of the world.
The chronic exposure of the upper aerodigestive tract to these and other risk factors is thought to produce field cancerization, a process in which patients with cancer or premalignant dysplastic lesions in the oropharyngeal mucosa are at significant risk for head and neck cancer. (See "Head and neck squamous cell carcinogenesis: Molecular and genetic alterations".)
The epidemiology of head and neck cancer and the risk factors for and pathogenesis of these tumors will be reviewed here. Issues related to pathology, diagnosis, staging, and therapy are considered separately. (See appropriate topic reviews).
Overall, head and neck cancer accounts for more than 550,000 cases annually worldwide . Males are affected significantly more than females with a ratio ranging from 2:1 to 4:1. The incidence rate in males exceeds 20 per 100,000 in regions of France, Hong Kong, the Indian subcontinent, central and eastern Europe, Spain, Italy, Brazil and among African Americans in the Unites States. Mouth and tongue cancers are more common in the Indian subcontinent, nasopharyngeal cancer is more common in Hong Kong, and pharyngeal and/or laryngeal cancers are more common in other populations .
In the United States, head and neck cancer accounts for 3 percent of malignancies, with an estimated 53,000 Americans developing head and neck cancer annually and 11,500 dying from the disease . The incidence in African American men during the years 1987 to 1991 was 24 per 100,000, approximately 50 percent higher than in white American men . The mortality associated with head and neck cancer in African Americans is also higher than in whites (median overall survival 21 versus 71 months) . The poorer prognosis appears to be due in large part to poorer outcomes in patients with oropharyngeal cancer, which is much less common in black compared with white patients (4 versus 34 percent). In this study, HPV positivity was much less common in black patients (4 versus 34 percent). (See "Human papillomavirus associated head and neck cancer", section on 'Prognosis'.)