Epidemiology of malignant tumours of the nasopharynx in France: retrospective and prospective studies.

Certain epidemiological conclusions have been drawn from a retrospective study of 509 cases of NPC treated in France. NPC was found to represent 3% of cancers of the upper digestive and respiratory tracts and 80% of nasopharyngeal malignancies in adults; 30% are squamous-cell carcinomas. The sex ratio was found to be 3:1. Less than 50% of cases occur in natives of France. A prospective study initiated by the Institut Gustave Roussy lead to the collection of data on 133 new cases of NPC treated in France in 1975 and 1976. The annual rate of NPC in France is about 0.3/100,000. A number of factors set apart well-differentiated epidermoid carcinomas from other forms of NPC: sex ratio (20:1), age of patients, geographic origin and the use of tobacco were similar to those seen in cases of epidermoid carcinomas of the upper digestive and respiratory tracts.