The disease is caused by mutations in the NF1 gene, and the risk of various types of tumors, especially those derived from the embryonic neural crest, including pheochromocytoma, leukemia, glioma, rhabdomyosarcoma, astrocytoma, and malignant peripheral nerve sheath tumor, is higher in individuals with NF1 mutations than in the general population [5]. This evidence concerns the gene NF1 and malignant peripheral nerve sheath tumor.