Squamous carcinoma of the nasopharynx.

Nasopharyngeal carcinoma is an unusual neoplasm among squamous cell carcinomas of the head and neck. The tumor is rare in most parts of the world but is strikingly common in several Asian subpopulations, notably Chinese in Hong Kong and Guangdong Province. The Epstein-Barr virus is intimately related to the disease and elicits the formation of antibodies that are useful for diagnosis and follow-up study. The virus has not been conclusively shown to cause nasopharyngeal cancer, however.Histologically, nasopharyngeal carcinoma is anaplastic in 75% of cases and better differentiated in 25% of patients. All tumors are treated by high-dose irradiation to the primary site and both sides of the neck. Surgical treatment, in the neck only, is reserved for irradiation failures. The prognosis is better in patients younger than 40 years, in patients without clinical cervical nodal involvement and, unexpectedly, in patients with anaplastic tumors.