Others have found alterations such as structural alterations of PDGFRA (platelet-derived growth factor-α) in 26% of MPNST samples [22]; increased expression of EGF-R (epidermal growth factor receptor) by immunohistochemistry in MPNSTs [23]; and IGFR1 gene amplification in 24% of MPNSTs [24]. The gene discussed is EGFR; the disease is malignant peripheral nerve sheath tumor.