Soft tissue
Adipose tissue
Subconjunctival herniated orbital fat

Author: Ivy John, M.D. (see Authors page)

Revised: 24 May 2017, last major update November 2016

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Subconjunctival herniated orbital fat

Cite this page: Subconjunctival herniated orbital fat. PathologyOutlines.com website. http://pathologyoutlines.com/topic/softtissueadiposeshof.html. Accessed October 21st, 2017.
Definition / general
  • Rare entity; first described in path literature in 2007 (Am J Surg Pathol 2007;31:193)
  • Prolapsed intraconal fat due to dehiscence of tenon capsule precipitated by age, disease, trauma or surgery
  • Typically occurs in elderly obese men
  • Presents as small (up to 2.5 cm), raised, convex, yellow, compressible mass in the superotemporal quadrant of the eye (Optom Vis Sci 2015;92:1021, Figure 1 & 2)
  • Unilateral or bilateral
  • Low recurrence rate after simple excision
Essential features
  • Rare entity, caused by forward movement of intraconal fat due to dehiscence of tenon capsule precipitated by age, disease, trauma or surgery
  • Typically presents in elderly obese men as a small, raised, yellow, compressible mass in the superotemporal quadrant of the eye
  • Composed of an admixture of mature adipocytes, delicate fibrovascular septae, Lochkern cells and floret-like giant cells
  • Principal differential diagnosis includes pleomorphic lipoma and atypical lipomatous tumor
Case reports
Clinical images
Images hosted on other servers:

Prolapsed orbital fat

Microscopic (histologic) description
  • Composed of uniformly shaped mature adipocytes separated by a delicate fibrovascular septae
  • Scattered Lochkern cells (adipocytes with enlarged nuclei containing intranuclear vacuoles) and floret-like giant cells (multinucleated giant cells with a wreath like arrangement of bland, uniform, often vacuolated nuclei)
  • Varying numbers of inflammatory cells, including lymphocytes, plasma cells, histiocytes and mast cells
Microscopic (histologic) images
Images hosted on PathOut server, contributed by Ivy John, M.D.:

Herniated orbital fat - COW #426

Positive stains
Differential diagnosis
  • Pleomorphic lipoma:
    • Different location; PL often involves soft tissues of back and shoulder of elderly men
    • Areas typical of spindle cell lipomas, including variably myxoid stroma, wire-like collagen and bland spindle cell proliferation are focally present
    • Floret-like giant cells show notable nuclear enlargement and hyperchromasia

  • Well differentiated liposarcoma:
Board review question #1
Regarding SHOF, which of the following statements are true:

A. SHOF is associated with MDM2 amplification.
B. Floret-like giant cells with nuclear hyperchromasia and pleomorphism are typically seen in SHOF.
C. The nuclei of Lochkern cells and floret-like giant cells in SHOF are highlighted by CD34 immunohistochemistry.
D. SHOF has an aggressive course and the management includes radiation therapy.
Board review answer #1
C. (Although not necessary for diagnosis), the nuclei of Lochkern cells and floret-like giant cells in SHOF are highlighted by CD34 immunohistochemistry.