Interestingly, other spindle cell tumors harboring RAF1, BRAF, and NTRK1/2 fusions and further characterized by S100 and CD34 co-expression (discussed hereafter, see Section 2.3), demonstrate a close proximity to some infantile fibrosarcomas by RNA unsupervised hierarchical clustering analysis [21]. This evidence concerns the gene RAF1 and spindle cell neoplasm.