Daimaru et al.[13] later suggested broadening the definition to include the following: one, tumors in patients without NF-1 that are microscopically compatible with a malignant schwannoma and contain focal rhabdomyoblasts; and two, tumors consisting predominantly of rhabdomyoblastic differentiation with focal Schwann cell elements occurring within a nerve or in patients with NF-1. Here, NF1 is linked to malignant peripheral nerve sheath tumor.