The cell of origin of ESFT is still unknown. The most widely held view at present is that ESFT is derived from pluripotent neural crest cells that have features of parasympathetic post-ganglionic cholinergic neurons [13–16]. One study using cDNA expression microarrays revealed a high similarity between the pattern of gene expression in ESFT cells and that in endothelial and fetal neural crest-derived cells [17]. In another study, it was demonstrated that in vitro expression of EWS-FLI1 or EWS-ERG in bone marrow stromal cells alters their morphology and blocks their differentiation along osteogenic and adipogenic
lineages [