Immunohistochemical and histologic study of cervical lymphoepithelial cysts.

Four cases of lateral cervical cysts were reported. All cyst walls were lined with keratinized stratified squamous epithelium, and contained lymph follicles with well-defined germinal centers. Ectopic salivary gland tissue was found in one case. Histochemical examination by the immunoperoxidase method revealed the existence of carcinoembryonic antigen (CEA). However, alpha-feto protein (AFP) and amylase were not detected in any of the cysts. The cyst fluid contained high levels of CEA and high titers of salivary type amylase, but AFP was negative. These results do not support any one of the theories concerning the etiology of cervical lymphoepithelial cysts. It seems likely that cysts derive from both epithelial remnants of the branchial apparatus and from salivary gland inclusions in lymph nodes.