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Zhang Wei, Zeng Xuesi, Jiang Yiqun, Xu Xiulian, Chen Hao, Sun Jianfang. Department of Pathology, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China Corresponding author: Sun Jianfang, Email: fangmin5758@aliyun.com ��Abstract�� Objective To analyze clinical and pathological features of palisaded encapsulated neuroma ��PEN��. Methods Demographic, clinical and pathological data on seven patients with PEN were collected and retrospectively analyzed. Results The average age of onset was 32 years ��range, 22-41 years�� with a male/female ratio of 2 �� 5. Lesions were solitary, small, soft-to-firm, skin-colored, red or yellowish-white papules in these patients. No patients reported subjective symptoms. Histopathology showed an isolated encapsulated well-marginated benign neoplasm in the dermis, which mainly consisted of proliferating Schwann's cells arranged in a sarciniform pattern. There were artificial fissures in tumor tissues. Immunohistochemical study revealed positive staining for S100 protein, but negative staining for smooth muscle actin and epithelial membrane antigen. Conclusions The diagnosis of palisaded encapsulated neuroma is mainly based on histopathological study. In clinic, it should be differentiated from schwannoma, neurofibroma and leiomyoma.