Rather, these assays detect EWSR1 rearrangements, which is important for differential diagnosis with other sarcoma subtypes that harbor EWSR1 fusions with non-ETS genes (e.g., desmoplastic small round cell tumors (DSRCTs), or EWSR1-NFATc2-translocated sarcomas). This evidence concerns the gene EWSR1 and desmoplastic small round cell tumor.