PAPILLARY ECCRINE ADENOMA - AN ULTRASTRUCTURAL AND IMMUNOHISTOCHEMICAL STUDY

A 45-year-old African American man presented with a small, solitary, n onulcerated cutaneous lesion of the right thigh of many years duration , which was excised. Light microscopically, the lesion consisted of an oval, well-circumscribed, intradermal proliferation of tubules, which were often dilated and lined by a double layer of tumor cells with co nspicuous intraluminal papillations. Ultrastructurally, there was evid ence of both intradermal eccrine duct and eccrine secretory coil diffe rentiation. Although the majority of tumor cells resembled cells of th e intradermal eccrine duct, occasional myoepithelial tumor cells and r are tumor cells having secretory granules and resembling dark mucous c ells were indicative of eccrine secretory coil differentiation. The po sitive immunoshistochemical staining for S-100 protein, CEA, EMA, and vimentin supported these ultrastructural findings.