Membranous basal cell adenoma of parotid gland, dermal cylindromas, and trichoepitheliomas:Comparative histochemistry and ultrastructure

Abstract
A basal cell adenoma of parotid, eccrine dermal cylindromas and trichoepitheliomas occurring in the same patient were examined by light microscopy, EM and histochemistry. The eccrine and parotid adenomas were similar structurally and histochemically except for the presence of Langerhans cells in the cutaneous adenoma and well differentiated mucinous cells in the parotid tumor. The 2 hamartomas found in this individual may represent the effect of a single pleiotropic gene acting on ontogenetically related stem cells.