Phakomatous choristoma of the eyelid: Immunohistochemical observation

Phakomatous choristoma of the eyelid

“…Immunohistochemical studies were performed in eight of the reported phakomatous choristomas and revealed positivity for S-100 in all cases [2,3,7,12,13,14,15,16] and positivity for vimentin in seven cases [2,3,7,12,13,14,16]. The here reported case showed the same immunohistochemical results.…”

“…Cytokeratins are present in the lens during the early stages of development and disappear after the 8th week in the human embryo [8]. Staining for cytokeratins was reported to be negative in most reported cases [3,7,15], including the tumor shown here. Rosenbaum et al reported a focal cytoplasmic staining of the epithelial cells with a keratin cocktail [13].…”

Phakomatous choristoma: A rare orbital tumor presenting as an eyelid mass with obstruction of the nasolacrimal duct

“…4,6 The epithelioid islands demonstrated intense staining with S-100, which has been shown to be positive in rabbit lens cells. 5 The immunoreactivity to alpha and beta crystallin in our patient has been previously described as further evidence of the lenticular origin of this tumor. 6 Phakomatous choristoma also characteristically stains positive for vimentin, 5-7 although this stain was not performed in our patient.…”

“…2 Our findings support the currently accepted theory that this is a rare, benign tumor of lenticular anlage. [1][2][3][4][5][6][7][8][9] The diagnosis of phakomatous choristoma in our patient was based on clinical correlation with previously reported histopathologic and immunohistochemical observations. The characteristic histopathological findings include 1,3,4,6 (1) a thick basement membrane surrounding pseudoglandular structures embedded in a collagenous stroma, (2) eosinophilic material in center of the epithelial islands resembling the cortex of normal and cataractous lenses, and (3) degenerated epithelial cells similar to "Wedl" cells observed in posterior subcapsular cataracts.…”

“…[1][2][3][4][5][6][7][8][9] It is thought to be secondary to the migration of the tumor cells early in the embryogenesis of the eye during the optic vesicle stage toward the region of the embryonic choroidal fissure. 4 It almost always presents as an isolated abnormality external to the globe, although a report of association with coloboma and hypoplastic optic nerve has been described.…”