The majority of malignant tumors occurring in the nasopharynx are carcinomas usually of the epidermoid type, either undifferentiated or of varying degree of differentiation. Lymphoepithelioma is now accepted by most authorities as a poorly differentiated variant of epidermoid carcinoma.
The diagnosis of nasopharyngeal carcinoma is often made after a long delay when the disease has already become advanced. This is largely because nasopharyngoscopy is a difficult procedure except in the hands of the expert. It is not possible to perform this procedure in the presence of trismus (not a rare complication resulting from the lateral spread of the carcinoma to the pterygoid muscles), or when there is a hyperactive pharyngeal reflex, in which case general anesthesia is required. Therefore, if a method which offers simplicity of execution and an acceptable degree of reliability in demonstrating nasopharyngeal lesions could be found, it would go a long way to minimize the diagnostic