Necrobiosis Lipoidica Diabeticorum

A 42-year-old woman with Type 1 diabetes mellitus (HbA1c 7.8%) presents with symmetric, painless plaques on the pretibial surfaces of both legs that began as red-brown papules 3 years ago. Examination reveals the lesions marked **A** in the diagram: well-demarcated plaques with a waxy, atrophic, yellow-brown center, prominent telangiectasias, and a slightly raised violaceous-erythematous border. Two older lesions show superficial ulcerations after minor trauma. A punch biopsy from the active inflammatory border is performed. Which of the following histopathologic findings is MOST characteristic of the lesion marked **A** and would distinguish it from granuloma annulare?