An annular lesion on the back.

Histologic examination revealed a central melanocytic lesion consisting of occasional small nests and single cells at the dermoepidermal junction (Figure 2). Nests of cytologically uniform melanocytic cells that exhibited maturation with depth were seen within the papillary dermis. No dermal mitoses were observed. There was a moderate perivascular and inflammatory cell infiltrate composed of lymphocytes and eosinophils within the superficial dermis (Figure 3). Some distance away from the melanocytic lesion, there was marked focal spongiosis, with fibrinous exudate overlying the corneal layer (Figure 3). The appearances were consistent with a benign melanocytic nevus with an eczematous halo (Meyerson nevus). One month later, the area remained mildly itchy, but treatment with a moderately potent topical steroid cream led to rapid resolution of symptoms.