Non-fibrosing sclerosing epithelioid fibrosarcoma: An unusual variant.

Sclerosing epithelioid fibrosarcoma (SEF), first described in 1995, is a rare aggressive sarcoma morphologically defined by "epithelioid fibroblasts arranged in distinct cords and nests in a densely sclerotic, hyalinised stroma". SEF can mimic metastatic carcinoma within desmoplastic stroma, lymphoma and other mesenchymal neoplasms such as myoepithelioma, making it difficult to diagnose. In a subset of cases there is morphological overlap between SEF and low grade fibromyxoid sarcoma (LGFMS), a low grade fibroblastic sarcoma. Progression of LGFMS to SEF in single cases is well documented. Recent studies detected EWSR1-CREB3L1 fusion transcripts in a high proportion of SEF. This article is protected by copyright. All rights reserved