The absolute role of macrophages in tumorigenesis in the NF1 context is not clear despite their abundant presence in pNF and even more so in MPNSTs in both mice and humans.100 Inhibiting the receptor for macrophage M-CSF using PLX3397 successfully decreased macrophage density and promoted tumour regression in a fraction of the mice tested, but only once pNFs had been established. Here, NF1 is linked to neoplasm.