ABSTRACT
The origin of Paget cells in extramammary Pagets disease is uncertain, however, some ultrastructural surveys revealed differentistion of Paget cells toward sweat gland apparatus. This is supported by recent immunohistochemical studies that Paget cells are irnmunohistochemically shown to react with antikeratin monoclonal antibodies specific to simple epithelia. In this siudy, seven cases of extramammary Pagets disease were immunohistochemically investigated with adenokeratin, carcinoembryonic antigen(CEA), involucrin by peroxidase-antiperoxidase(PAP) techniques. The results were as follow : l. Epidermis, hair follicies and sebaceous glands revealed negative immunoreacativity for adenokeratin in all cases. Sweat glands(6/7), Paget cells(6/7) and underlying adenocarcinoma revealed positive immunoreactivity for adenokeratin. 2. Epidermis, hair follicles and sebaceous glands(6/7) revealed negative immunoreactivity for CEA. Sweat glands, Paget cells and underlying adenocarcinoma revealed positive immunoreactivity for CEA in all cases. 3. Lower epidermis, sweat glands(6/7), Paget cells and underlying adenocarcinorna revealed negative irnmunoreactivity for involucrin. Upper epidermis, hair follicles and sebaceous glands(5/7) revealed positive immunoreactivity far involucrin. Based on these results, Paget cells of extramammary Pagets disease are considered to be derived from the sweat glands.