Soft tissue
Fibroblastic / myofibroblastic tumors
Sclerosing epithelioid fibrosarcoma (SEF)

Author: Cliff Sullivan, M.D. (see Authors page)
Editor: Jerad M. Gardner, M.D.

Revised: 12 September 2016, last major update June 2013

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: Sclerosing epithelioid fibrosarcoma [title]

Cite this page: Sclerosing epithelioid fibrosarcoma (SEF). PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/softtissuesclerosingepithelioidfibrosarcoma.html. Accessed December 9th, 2016.
Definition / General
  • Rare, slow growing, sarcoma of deep soft tissue with epithelioid tumor cells in nests and cords set in hyalinized fibrous stroma
  • WHO Classification: Fibroblastic/Myofibroblastic Tumors
  • First described in 1995 (Am J Surg Pathol 1995;19:979)
Epidemiology
Sites
Clinical Features
Prognostic Factors
  • Location appears to be linked to prognosis (Clin Orthop Relat Res 2008;466:1485):
    • Head and neck - 46% dead of disease
    • Upper extremity - 38% dead of disease
    • Trunk - 26 % dead of disease
  • No effect on prognosis:
    • Gender - no effect on local recurrence
    • Tumor size - metastatic disease independent of tumor size
Case Reports
Treatment
Gross Description
  • Mean size: 9 cm (range 4 - 22 cm)
  • Grossly well circumscribed
  • Lobulated, bosselated, or multinodular
  • Firm, gray-white cut surface, occasionally cystic, calcified, myxoid
  • May invade bone
  • Usually no necrosis
Gross Images

Images hosted on PathOut servers:

Courtesy of Mark R. Wick, M.D.



Images hosted on other servers:

Lobulaulated, multinodular white mass

Micro Description
  • Low power: hypocellular tumor with large areas of hyalinized fibrous stroma
  • Mid power: nests and cords of small to medium sized, round to ovoid, relatively uniform epithelioid cells; some tumors have a more alveolar pattern; may have areas resembling fibroma, low grade fibromyxoid sarcoma, conventional fibrosarcoma; occasionally tumors have hemangiopericytoma-like vasculature, vascular invasion, necrosis (Histopathology 1998;33:354)
  • High power: often clear to scant eosinophilic cytoplasm and uniform bland nuclei with vesicular or finely stipple chromatin and small basophilic nucleoli; mitoses are inconspicuous, < 4 MF / 10 HPF
Micro Images

Images hosted on PathOut servers:

Courtesy of Mark R. Wick, M.D.



Images hosted on other servers:

Epithelioid cells with clear cytoplasm

Cords of epithelioid cells within a eosinophilic hyalinized stroma

Sclerosing epithelioid-like areas

Alveolar pattern



Epithelioid cells in a densely collagenized matrix

Hemangioper-
icytoma-like vascular pattern

Resemblance to carcinoma

Cytology Description
  • Only one case report (Diagn Cytopathol 2010;38:748): clusters of moderately overcrowded epithelioid cells with background of histiocytes and lymphocytes and a few mesothelial cells
  • Nuclei eccentrically placed and pleomorphic with oval, spindled, or cleaved shape
  • Uniformly fine, granular chromatin and thin nuclear membrane
  • Numerous small nucleoli
  • Occasional multinucleated cells
Positive Stains
Negative Stains
Electron Microscopy Description
Molecular / Cytogenetics Description
Differential Diagnosis