Apocrine Cystadenoma of the Eyelid, a Rare Neoplasm: Expanded Immunohistologic Profile

An 83-year-old woman experienced the slow enlargement of a right lower eyelid mass. Histopathologic examination of the excised tissue showed a mucin-filled cystic tumor emanating from an apocrine bilayer that displayed bleb-like apocrine decapitation secretion. The outer flattened myoepithelial layer of the bilayer reacted with immunohistochemical stains for smooth muscle actin and calponin. In foci, the tumor exhibited a cribriform architecture with small pockets of mucin. Tumor cells were reactive for cytokeratin 7, Gross Cystic Disease Fluid Protein 15 (BRST-2), estrogen and progesterone receptors, androgen receptors, mammaglobin, epithelial membrane antigen, and GATA3. Ki67 showed a very low proliferation fraction. The lesion exemplifies the fourth instance of an eyelid apocrine cystadenoma in the literature.