Papillary oncocytoma of the eyelid. A previously undescribed tumor of apocrine gland origin.

Oncocytomas are uncommon tumors arising within the ductular cell lining of glandular structures. The oncocytic cells are characteristically large and rich in eosinophilic cytoplasm. Electron microscopic studies show densely packed mitochondria with irregular, whorled, or fragmented cristae. Ocular adnexal oncocytomas have been reported to arise in the caruncle, lacrimal gland, and lacrimal sac. The authors recently encountered an oncocytic tumor occurring in a most unusual location, the skin of the medial lid margin and commissure. Microscopically, the lesion was papillary and cystic in architecture, and arose from an adjacent apocrine gland of the eyelid margin (gland of Moll). Electron microscopic studies showed that the tumor cells were packed with malformed mitochondria to the exclusion of other organelles. This is the first report documenting an oncocytic lesion arising in the skin from an adnexal gland.