PDGFRA and gastrointestinal stromal tumor: Recently, Yamamoto et al.[23] reported that KIT and platelet-derived growth factor receptor-alpha (PDGFRA) mutations are very rare events in NF-1 GIST and that activation of the RAS-MAPK pathway associated with inactivation of the NF-1 gene may play an important role in the development of GIST in NF-1 patients.