NF1 and neoplasm: Finally, 15% of patients with GISTs do not have a detectable mutation in either KIT or PDGFRA. These tumours are a genomically heterogeneous group with a variety of genetic anomalies previously reported, including mutations in B-Raf proto-oncogene (BRAF), succinate dehydrogenase (SDH) and neurofibromin 1 (NF1), however they do demonstrate phosphorylated KIT although the mechanisms behind this are unclear ([49], [50], [51]).