The pathology of head and neck tumors: carcinoma of the nasopharynx, Part 11.

The past decade has witnessed extraordinary advances in the epidemiology, virology, and immunology of carcinomas of the nasopharynx. There has not been a parallel growth in the study of morphologic expressions of the neoplasms. In great part, this has been due to a lack of a universally accepted histologic classification. As a consequence, correlation between histology and other factors relating to the pathogenesis of these neoplasms has been impeded. The World Health Organization (WHO) has proposed a histologic classification of nasopharyngeal carcinomas as squamous-cell, nonkeratinizing, and undifferentiated. This report presents and argument in favor of using the WHO classification and a hypothesis relating to the histogenesis of the 3 types of nasopharyngeal carcinoma.