Pleomorphic adenoma (formerly chondroid syringoma) of the eyelid margin with a pseudocystic appearance

Among the adenomas and adenocarcinomas spawned by the adnexal glands of the eyelids, pleomorphic adenoma (also referred to as benign mixed tumor or chondroid syringoma in dermatopathology) is among the rarest. Pleomorphic adenomas (PAs) can arise from sweat glands in the dermis of the eyelid skin and must be distinguished from those of the accessory lacrimal glands of Krause and Wolfring. We describe an eyelid margin skin PA that appeared clinically to be a cyst and was not associated with an accessory lacrimal gland. Histopathologically, the lesion was circumscribed but nonencapsulated and composed of branching ductular structures with a double layer of epithelial cells set in a myxoid and sclerotic stroma that did not contain cartilage. The outer ductular (myoepithelial) cells delaminated to populate the stroma. Histochemistry disclosed abundant extracellular mucopolysaccharides that conferred the "cystic" character clinically. The inner ductular cells were uniformly positive for cytokeratin 7 and focally for gross cystic fluid disease protein-15, an apocrine marker. The inner and outer ductular cells were negative for alpha-smooth muscle actin. These pathologic findings support an apocrine (gland of Moll) origin for this tumor, which is consistent with the fact that there are no eccrine glands at the eyelid margin.