FISH showing rearrangement of EWSR1 and CREB3L1 genes in Cases 1 and 2. A. Case 1, CREB3L1 break apart (arrows) (red centromeric, green telomeric). B. Case 1, EWSR1 unbalanced rearrangement with loss of telomeric part (green). C. Case 2, CREB3L1 break apart (arrows)(red centromeric, green telomeric). D. Case 2, EWSR1 unbalanced rearrangement with loss of telomeric part (green).