NF1 and neoplasm: Woodruff et al.[12] also proposed three criteria for determining whether a neoplasm could be truly classified as a malignant ‘Triton’ tumor or not: one, arises from a peripheral nerve, or in a patient with NF-1, or in a location typical for peripheral nerve tumors, or represents a metastasis from such tumor; two, demonstrates the growth characteristics of Schwann cells; and three.