Moreover, there is a risk of falsely diagnosing a tumor as Ewing sarcoma based on FISH, because break-apart of the EWSR1 gene can also be observed in other sarcoma entities such as desmoplastic small-round-cell tumor (DSRCT), clear cell sarcoma, angiomatoid fibrous histiocytoma, extraskeletal myxoid chondrosarcoma, and a subset of myxoid liposarcoma [34]. Here, EWSR1 is linked to clear cell sarcoma.