Abstract
We describe a 43-year-old woman with pigmented mammary Paget's disease (PMPD) on the left nipple. Two years before our initial examination, she noticed a black lesion on her left nipple which gradually increased in size. Dermoscopic examination revealed the presence of irregular blotches, blue-white structures, irregular streaks showing the features of malignant melanoma (MM). Histopathologic findings included numerous pagetoid cells with clear and abundant cytoplasm in the epidermis, upper dermis, and inner side of mammary ducts. Immunohistochemical study showed that those cells were positive for CEA and CK-7 and negative for HMB-45 and melon-A. Although there have been scarce reports on the dermoscopic characteristics of MPMD, it seems that PMPD and MM have similarities with each other. We further documented the resemblance between the two diseases by exhibiting dermoscopic and immunohistochemical findings.[Skin Cancer (Japan) 2013 ; 28 : 287-291]
