IGF1R and gastrointestinal stromal tumor: Besides functional in vitro and in vivo studies, in-depth analysis of WT GISTs genomic and transcriptomic profile by microarray or next generation sequencing techniques will help to clarify IGF1R's role as a marker or therapeutic target, and the mechanism of its over-expression in this rare subtype of GIST that is poorly responsive to conventional therapies [37,48,49].