Comparing the mutation frequencies with those obtained across all cancer types (Lawrence et al, 2013; Watson et al, 2013), the two NF1-associated MPNSTs developed in the same patient (0.89–1.79 mutations per Mb) fall in the low range of somatic mutation frequency, whereas the two independent sporadic MPNSTs (15.33–18.38) are in the highest frequency ranges. This evidence concerns the gene NF1 and cancer.