Annular erythematous plaques on the right chest wall of a 55-year-old woman

Case report A fifty-five-year-old postmenopausal woman first visited our dermatological department in February 2009 because of a history of progressive appearance of annular pruritic plaques on the right chest wall for 1 month (Figure 1). She had went to multiple local medical doctors for help; and under the impression of eczema or fungal infection, the patient was treated empirically with topical steroid and antifungal drugs, but the therapeutic response was poor. On physical examination, an annular lesion with central clearing and erythematous border was detected on her right chest wall. A potassium hydroxide preparation test was performed but no fungal elements were detected. Then a diagnostic skin biopsy was performed (Figures 2A and 2B).