The benign nature of the tumor is supported by the following features: (i) sharply demarcated margins (often encapsulation); (ii) a focal presence of Antoni B areas; (iii) disproportion between hypercellularity, nuclear pleomorphism, and the amount of necrosis and mitoses; and (iv) strong and diffuse S100 protein and SOX10 immunoexpression. The gene discussed is SOX10; the disease is neoplasm.