A. Ryska et al., INTRATHYROIDAL LYMPHOEPITHELIAL CYST - A REPORT OF 2 CASES NOT ASSOCIATED WITH HASHIMOTOS-THYROIDITIS, Pathology research and practice, 193(11-12), 1997, pp. 777-781
Two cases of intrathyroidal lymphoepithelial cyst are described. Both
of them were solitary, one being found incidentally in a patient opera
ted on for a multinodular goiter, the other being clinically obvious a
s a cold nodule. They exhibited features of cysts of branchial cleft o
rigin, i.e. squamous cell lining epithelium and abundant lymphoid tiss
ue with reactive germinal centers. The thyroid gland parenchyma showed
a discrete lymphoid infiltration consistent with the diagnosis of foc
al lymphocytic thyroiditis. In the first case a single epidermoid soli
d cell nest was found. The histogenesis of intrathyroidal lymphoepithe
lial cysts remains unclear, but their origin from cystically degenerat
ed ultimobranchial body remnants (solid cell nests) seems to be most p
robable. This assumption is supported by a similar immunohistochemical
profile of solid cell nests and epithelial cells lining the cysts and
also by the presence of one solid cell nest in the proximity to the c
yst in one of our cases.