Paget's Disease of Vulva
High power view shows large pale tumor cells which are sometimes mistaken for malignant melanoma. The cells contain intracytoplasmic mucin and are positive for mucicarmine, PAS and alcian blue. Immunohistochemical profile includes positivity for MUC1, MUC5AC, CK7, CAM5.2, EMA, CEA, and GCDFP-15. Majority of the cases of vulvar Pagetís disease are not associated with underlying adenocarcinoma unlike mammary Pagetís disease.