Gronchi et al. argue that the difference in survival between NF-1 and non-NF-1 MPNST patients is due to NF-1 patients presenting later with larger tumors due to a failure of recognition of malignancy within large plexiform neurofibromas, and there is no biological basis for the difference in survival. The gene discussed is NF1; the disease is malignant peripheral nerve sheath tumor.