For cases in which the COL1A1-PDGFB rearrangement is not found, our experience shows that it is best to take a closer look at the morphology: if there is any suspicion of DFSP, other gene rearrangements should be sought using RNA sequencing (RNA-seq) or next-generation sequencing techniques; if the morphology is not suggestive of DFSP, the most likely diagnosis will fall within the “FCTN-MLDDH/PDF” spectrum. This evidence concerns the gene PDGFB and dermatofibrosarcoma protuberans.