Lymphoepithelial cysts are relatively uncommon lesions with an uncertain etiopathogenesis 1. A lymphoepithelial cyst can occur in any organ that has normal or accessory lymphoid tissue. The neck and the oral cavity are the most frequent sites for lymphoepithelial cysts, followed by the pancreas and thyroid gland 1. We report a lymphoepithelial cyst found incidentally on the supraglottic surface of the larynx, during an autopsy on an 82-year-old female. The gross evaluation revealed a smooth, white, soft to firm, mobile, loosely adherent, polypoid lesion on the vestibule of the larynx. Histological studies revealed a polypoid mass lined by nonkeratinized stratified squamous epithelium with a cyst in the center (Fig. 1). The cystic cavity was lined by a flattened layer of stratified squamous epithelium and filled with degenerating squamous cells and keratin debris (Fig. 2). The cyst wall showed fibrotic stroma with few embedded seromucinous glands (Fig. 3) along with a concentric layer of lymphoid tissue with absent germinal centers.
The term lymphoepithelial was first recommended by Bhaskar and Bernier 2 in their report on 468 cases of branchial cysts of the neck. Soon it was followed by the first case report of an oral lymphoepithelial cyst by Gold and Lewittown in 1962 1. Various theories on its pathogenesis have been proposed, of which two are most widely accepted. According to Knapp’s 3 obstruction theory, lymphoepithelial cysts are pseudocysts, rather than true cysts, and form as a result of obstruction in the crypt of a tonsil mouth or superficial ducts of minor salivary glands. In contrast, few authors suggest that these cysts develop as a result of proliferation of ectopic foci of glandular epithelium that become entrapped within nodal tissue 3. Clinically, a lymphoepithelial cyst presents as an asymptomatic, well-circumscribed, yellow to white, firm to soft, elevated submucosal nodule that is usually less than 1 cm in diameter.
Similar cystic lesions occurring in the epiglottis, composed of a well-defined tonsillar crypt-like epithelium and abundant follicular lymphoid tissue with germinal centers that resemble a palatine tonsil, are called tonsillar cysts. Other types of laryngeal cysts include epithelial (ductal, saccular), oncocytic, and traumatic cysts. Newman and colleagues, who coined the term ‘tonsillar cysts’, concluded in their study of laryngeal cysts in adults that lymphoid tissue is present in most laryngeal cysts and probably plays a role in their pathogenesis 4. It has hence been speculated that the presence of a scant amount of lymphoid tissue without germinal centers in a lymphoepithelial cyst wall could very well be a reactive process. Because of the inhomogeneous nature of the laryngeal cysts, Arens et al.5 suggested the subdivision of laryngeal cysts into congenital, retention, and inclusion cysts on the basis of their genesis and development rather than histomorphology. On the basis of the above discussion, we classified the vestibular laryngeal cyst in this case as a lymphoepithelial cyst. To the best of our knowledge, no case of primary lymphoepithelial cyst of the vestibule has been reported in the English literature.
Conflicts of interest
There are no conflicts of interest.
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