Extramammary Paget's Disease Visit: Dermatopathology Site Visit: Pathology of Extramammary Paget's Disease Abstract: Extramammary Paget's disease: Evaluation of the histopathological patterns of Paget cell proliferation in the epidermis.J Dermatol. 2011 Nov;38(11):1054-7. doi: 10.1111/j.1346-8138.2011.01268.x. Epub 2011 Sep 23. Extramammary Paget's disease (EMPD) is a rare malignant skin neoplasm. The prototypical pattern of tumor cell proliferation in the epidermis includes single cells and/or nest arrangements, mainly in the lower epidermis. Although other patterns have been recognized, they have not previously been investigated in detail. We aimed to examine the patterns of tumor cell proliferation in the epidermis. Surgical specimens were obtained from 38 patients with primary EMPD. We defined six patterns, in addition to the prototypical one: (i) glandular; (ii) acantholysis-like; (iii) upper nest; (iv) tall nest; (v) budding; and (vi) sheet-like. There were 26 mal