Pigmented Extramammary Paget’s Disease of the Axilla: Two Case Reports and a Literature Review

Yi-Xiao Wang,1– 4,* Xiao-Mei Cui,5,* Qing Zhang,6 Xiao-Qing Xu,1– 4 Yao Sun,1– 4 Min Gao,1– 4 Li-Xiong Gu5 1Department of Dermatology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230032, People’s Republic of China; 2Institute of Dermatology, Anhui Medical University, Hefei, Anhui, 230032, People’s Republic of China; 3Key Laboratory of Dermatology (Anhui Medical University), Ministry of Education, Hefei, Anhui, 230032, People’s Republic of China; 4Collaborative Innovation Center of Complex and Severe Skin Disease, Anhui Medical University, Hefei, Anhui, 230032, People’s Republic of China; 5Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, 226001, People’s Republic of China; 6Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, 226001, People’s Republic of China*These authors contributed equally to this workCorrespondence: Li-Xiong Gu, Department of Dermatology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, 226001, People’s Republic of China, Email [email protected] Min Gao, Department of Dermatology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230032, People’s Republic of China, Email [email protected]: Extramammary Paget’s disease is a rare intraepithelial adenocarcinoma that mainly occurs in areas rich in apocrine sweat glands, such as the vulva, perianal region, and, less commonly, in the axillary skin. Owing to the varied manifestations of extramammary Paget’s disease, it is often misdiagnosed. Particularly, pigmented extramammary Paget’s disease (PEMPD) can be mistaken for superficial spreading melanoma, Bowen’s disease, pigmented superficial basal cell carcinoma, or seborrheic keratosis. Here, we report two cases of women with axillary pigmented plaques who were confirmed as PEMPD through histopathological and immunohistochemical analyses. One of these patients was only 31 years old, which makes her the youngest reported case of PEMPD to date. All patients underwent Mohs micrographic surgery, and no recurrence or metastasis was observed postoperatively. PEMPD is a rare clinical variant that can resemble other pigmented lesions, both clinically and histopathologically. Therefore, this report underscores the importance of accurate differential diagnosis through immunohistochemistry.Keywords: pigmented extramammary Paget disease, axilla, histopathology, immunohistochemistry, Mohs micrographic surgery