EWSR1 and neoplasm: Indeed, our DSRTC-1 PDX maintained the histomorphology of the paired clinical tumor, expressed the pathognomonic EWSR1::WT1 gene fusion, showed some of the most frequent genomic aberrations observed in clinical DSRCT, including gains in chromosomes 1 and 3, and was characterized by a transcriptomic profile largely reproducing that of the originating tumor.