Skin nonmelanocytic tumor
Fibrous, fibrohistiocytic and myofibroblastic neoplasms
Fibrous histiocytoma-epithelioid


Topic Completed: 1 August 2012

Minor changes: 1 October 2020

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PubMed Search: Epithelioid fibrous histiocytoma

Vijay Shankar, M.D.
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Cite this page: Shankar V. Fibrous histiocytoma-epithelioid. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/softtissuefhepithelioid.html. Accessed October 21st, 2020.
Definition / general
  • Variant with 50% or more of tumor cells having epithelioid morphology
Epidemiology
Pathophysiology
Clinical features
  • Uncommon, usually presents as small (0.5 to 2 cm), solitary, very rarely multiple, skin colored elevated nodules
  • Usually seen on trunk and extremities, rarely in head and neck regions
Case reports
Treatment
Microscopic (histologic) description
  • Often exophytic with epidermal collarette
  • Circumscribed with uniform, medium to large angulated epithelioid cells (50%+ of tumor cells) that are often perivascular
  • Many binucleated cells are often seen
  • May be cellular (Am J Surg Pathol 1994;18:583)
  • Periphery shows typical features of dermatofibroma
  • Minimal inflammation, no prominent giant cells
Microscopic (histologic) images

AFIP images and Case #116
Histiocyte-like cells with abundant cytoplasm, no / rare spindle cells Histiocyte-like cells with abundant cytoplasm, no / rare spindle cells

Histiocyte-like cells with abundant cytoplasm, no / rare spindle cells

Epithelioid cells in hyalinized stroma

Epithelioid cells in hyalinized stroma

60 year old man with scalp lesion 60 year old man with scalp lesion 60 year old man with scalp lesion

60 year old man with scalp lesion


60 year old man with scalp lesion

60 year old man with scalp lesion

Vimentin+

Vimentin+

Factor XIIIa+

Factor XIIIa+

CD68-

CD68-

Keratin-

Keratin-

Melan A-

Melan A-



Images hosted on other servers:
Epithelioid cells with vesicular nuclei

Epithelioid cells with vesicular nuclei

Negative stains
Differential diagnosis
  • Epithelioid sarcoma: deep seated, granuloma-type clusters with necrosis, more atypia, keratin+, CD163-
  • Granuloma: epithelioid histiocytes in well formed clusters, surrounded by lymphocytes
  • Histiocytic sarcoma: marked atypia and mitotic activity
  • Melanoma: tight clustering of atypical cells, S100+, HMB45+
  • Rosai-Dorfman disease: multiple skin lesions and adenopathy, histiocytes are S100+ and pleomorphic with emperipolesis, also prominent B cells and plasma cells
  • Solitary epithelioid histiocytoma: dense eosinophilic and glassy cytoplasm, often with spiked cytoplasmic extensions, variable nuclear grooves and multinucleated cells, frequent lymphocytes and neutrophils, CD68+, CD163+ (Am J Surg Pathol 2006;30:521)
  • Spitz nevus: nevoid type clusters in periphery with spindle cell component, S100+
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