About a third of soft tissue tumors are recognized by gene fusions. Some of these fusions are not histotype specific and occur in entities with totally different clinicopathological features. A good example is the fusion between EWSR1 and genes of the CREB transcription factor gene family (CREB1 or ATF1) 1).

1)
Sciot R, Jacobs S, Calenbergh FV, Demaerel P, Wozniak A, Debiec-Rychter M. Primary myxoid mesenchymal tumor with intracranial location: report of a case with a EWSR1-ATF1 fusion. Histopathology. 2017 Nov 15. doi: 10.1111/his.13437. [Epub ahead of print] PubMed PMID: 29143432.