Nasopharyngeal Warthin's tumour: a metaplastic lesion.

Warthin's tumour arising from minor salivary glands of the nasopharynx is described in a patient with eosinophilic rhinitis and nasal polyposis. The microscopical features of this lesion were indistinguishable from those of Warthin's tumours of the parotid gland. The present case supports the histogenetic theory that the epithelial component of extraparotid Warthin's tumours represents reactive oncocytic metaplasia and hyperplasia induced by chronic inflammation rather than genuine neoplasia. It is suggested that the term Warthin's tumour is preferable to designations indicating neoplasia of these extraparotid lesions which are indistinguishable histologically and ultrastructurally from parotid and juxtaparotid adenolymphomas.