Hematoxylin-eosin staining revealed a palisaded granulomatous proliferation of epithelioid to multinucleated giant cells within the middle to deep reticular dermis. Within the proliferation, there were palisading granulomas with central elastolysis and broad bands of collagen. Elastotic fibers were seen adjacent to and within giant cells. A modest lymphoplasmacytic infiltrate surrounded the granulomas. The overlying papillary to middle reticular dermis demonstrated prominent solar elastosis and mildly ectatic vasculature. Asteroid bodies, mucin, necrobiosis, and eosinophils were not identified. A Verhoeff elastic stain demonstrated elastotic fibers surrounding the granuloma; central absence of elastic fibers within the granuloma is characteristic. Prominent elastolytic changes were observed adjacent to the area of granulomatous inflammation. Elastotic fragments were engulfed peripherally within giant cell histiocytes.
Erythematous Annular Plaques in a Necklace Distribution. Arch Dermatol. 2001;137(12):1647-1652. doi: