PDGFRA and gastrointestinal stromal tumor: Tumors are strongly positive for KIT by immunohistochemistry but mutations in KIT or PDGFRA (Platelet Derived Growth Factor Receptor Alpha) genes are rare among NF1 associated GISTs, contrast to the sporadic cases of GIST where somatic mutations in KIT or PDGFRA genes play a major pathogenesis [9], [11], [15].