[An immunohistochemical analysis of extramammary Paget's disease compared with mammary Paget's disease].

Fourteen cases of extramammary Paget's disease and five cases of mammary Paget's disease have been studied using stereomorphometric, histochemical, and immunohistochemical methods. The antibodies were anti-CEA, anti-EMA, 115D8 and DF3. Intracytoplasmic mucin was positive in Paget's cells, and both 115D8 and DF3 were detected intensely in all of Paget's cells. 115D8 and DF3 were also positive in the normal apocrine sweat gland, the intercellular canaliculi of the eccrine sweat gland, and the intraductal carcinoma of the breast. Therefore, we have concluded that extramammary Paget's disease is an intraepidermal adenocarcinoma originating in the apocrine sweat gland.