Atypical cells on reflectance confocal microscopy may not represent melanoma: A case of axillary pigmented extramammary Paget disease

• DOI: 10.1111/cup.13804
• Publication Date: 2020-07-09T11:10:26Z
• Authors: Nadiya Chuchvara; Catherine Reilly; Attiya Haroon; Cindy Wassef; Amin Maghari; Babar Rao
• Keywords: Histopathology; Paget Disease; Amelanotic melanoma; Extramammary Paget's disease

Abstract Pigmented extramammary Paget disease (PEMPD) is a rare intraepithelial carcinoma which can clinically resemble other pigmented neoplasms. Similarities to melanoma on dermoscopy, histopathology, and reflectance confocal microscopy (RCM) increase the risk of misdiagnosis and, consequently, mismanagement. Here, we describe case 67‐year‐old African American woman with large, axillary patch that exhibited features RCM, guiding clinician perform an excisional biopsy. While traditional histopathology resembled melanoma, immunohistochemistry staining was performed revealed PEMPD. We highlight uncommon clinical presentation PEMPD identify morphologic mimickers RCM—as well as differentiating features.