Characteristics of the epithelial component of parotid adenolymphoma.

Parotid adenolymphoma is composed of two histologic components, epithelial and lymphoid. Although some theories regarding the histogenesis of this tumor have long been disputed, there have been no definite conclusions. The purpose of this study was to clarify the origin of the epithelial components of this tumor using histochemical and immunopathological techniques, electron microscopy and a survey of HE-stained tumor sections. The results obtained indicated that the functions of the epithelial components were similar to those of the striated duct of the normal parotid gland, and morphological studies showed that the origin of the epithelial components may arise from parotid ductal inclusion in the lymphnodes in or around the parotid gland.