Two Cases of Apocrine Mixed Tumor

Abstract

Case 1. A 41-year-old man noticed a tumor measuring about 7.5 mm in diameter on his nose 6 months prior to presentation. Case 2. A 49-year-old man noticed a tumor about 16 mm in diameter on his upper lip a few years previously. A histopathological examination showed the tumor to be mainly composed of tubular structures. Some of the tubules displayed decapitation secretion. The stroma was edematous and myxoid. In addition cystic structures could be observed which contained eosinophilic amorphous material in case 2. Immunohistochemical examination using monoclonal antikeratin antibodies showed most of the tumor cells of case 1 to differentiate towards transitional portions between the dermal ducts and secretory segments of the sweat glands, whereas luminal cells with decapitation secretion differentiate toward the secretory regions. The keratin expression suggested tumor cells of case 2 to differentiate toward various regions ranging from dermal ducts to the secretary portions, while the cystic structures were observed to differentiate towards the dermal ducts.