A case of subungual epidermal cyst

We report a 45-year-old woman presenting with a painful subungual epidermal cyst on the 4th finger nail bed. Based on clinical features only, the lesion was initially suspected to be a glomus tumor. However, histopathological examination revealed an epidermal cyst on the nail bed. Subungual epidermal cysts are rare disorders that may cause pain and tenderness that increase according to tumor growth. They can mimic glomus tumors owing to their similar clinical manifestations. To differentiate subungual epidermal cysts from glomus tumors, imaging tools such as ultrasonography and magnetic resonance imaging can be used. Dermatologists should be aware that several kinds of tumors including epidermal cysts with clinical similarities may occur in the subungual area.