On immunohistochemistry, diffuse S-100 and SOX10 positivity, CD34 positive fibroblastic network, low Ki-67 proliferation index (<2–5%) and the absence of p53 staining favor ordinary or atypical cNF rather than malignant peripheral nerve sheath tumors (MPNST) [46]. The gene discussed is MKI67; the disease is malignant peripheral nerve sheath tumor.