Polypoid Spitz Nevus: Aided by Dermoscopic Examination / 대한피부과학회지

ABSTRACT

Spitz nevus is a benign melanocytic nevus, common in children or young adults, and it has histological features that are confused with those of malignant melanoma. Polypoid Spitz nevus is the benign counterpart of polypoid malignant melanoma. A 22-year-old woman presented with a solitary 1.5×1.5 cm-sized firm polypoid erythematous nodule on the left thigh. On dermoscopy, pink to yellowish lagoons intermingled by white fibrous septa were found but milky red globules or irregular linear vessels were not found. Therefore, melanoma almost could be ruled out cautiously. Histopathology showed symmetrical, well-circumscribed, polypoid architecture with predominant dermal nests of spindle cells. Immunohistochemically, the nevus cells were strongly positive for S-100 protein and negative for HMB-45. Thus, the diagnosis of polypoid Spitz nevus was made. Herein, we report a case of polypoid Spitz nevus that was differentiated from polypoid melanoma by histopathologic and dermoscopic findings.