Schwann Cell Tumor — Schwannoma

A 45-year-old woman presents with a slow-growing, painless mass along the course of her right radial nerve. Imaging shows a well-circumscribed, encapsulated lesion. Histopathology reveals a benign nerve sheath tumor with areas of compact, highly organized spindle cells arranged in fascicles, as marked **A** in the diagram. The tumor is S100 positive and can be cleanly separated from the nerve without requiring nerve resection. Which of the following best describes the pathological significance of the Antoni A pattern shown at **A**?