Soft tissue
Fibroblastic / myofibroblastic tumors
Elastofibroma

Author: Komal Arora, M.D. (see Authors page)

Revised: 15 August 2016, last major update July 2012

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

PubMed Search: Elastofibroma

Cite this page: Elastofibroma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/softtissueelastofibroma.html. Accessed December 8th, 2016.
Definition / General
  • Benign, poorly circumscribed pseudotumor of subscapular region, composed of collagen and coarse enlarged elastic fibers
  • Reactive hyperplasia involving abnormal elastogenesis
  • Also called elastofibroma dorsi
  • First described in 1961 by Jarvi and Saxen (Acta Pathol Microbiol Scand 1961;51:83)
Epidemiology
  • Usually age 55+ years
  • Associated with hard manual labor
  • Related changes found at autopsy in 13 - 17% of elderly
  • More common in women
Sites
  • More common on apex of scapula, usually right sided
  • Occasionally in deltoid muscle, infraolecranon area, hip, thigh, stomach
  • May be multiple, bilateral or familial
  • May be periosteal in origin
  • Slightly different amino acids from elastin
  • Has collagen types I - III (type II normally restricted to articular cartilage and ocular structures)
Case Reports
Treatment
  • Excise if symptomatic, does not recur
Clinical Images

Images hosted on PathOut servers:

MRI, courtesy of Mark R. Wick, M.D.



Images hosted on other servers:

Shoulder based tumors

Typical location (arrow)

Gross Description
  • Ill defined, rubbery, gray-white fibrous tissue mixed with yellow streaks of elastin
  • Up to 15 cm
Gross Images

Images hosted on PathOut servers:

Fibrocollagenous areas blend with fat (AFIP)



Images hosted on other servers:

Poorly defined fibroelastic tumor entrapping fat

Gray-white fibrous tissue mixed with fat

Micro Description
  • Collagen bundles alternate with large, thick eosinophilic elastic cylinders with a dense central core, elastic fibers may be fragmented into linear globules (beads on a string)
  • Often has irregular interdigitation into adipose tissue
Micro Images

Images hosted on PathOut servers:

Dorsi (left two) and elastic stain (right), courtesy of Mark R. Wick, M.D.

Paucicellular fibrous tissue mixed with fat



Thick, densely eosinophilic elastin bands are mixed with collagen

Elastin bands have serrated edges

Verhoeff elastin stain

Orcein (elastin) stain




Case of the Week #46



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Mature adipose tissue

Branched and unbranched
coarse elastin fibers



H&E and elastic stain

Verhoeff elastin stain highlights elastin fibers and the bead-like arrangement of the elastin globules

Cytology Description
Positive Stains
Electron Microscopy Description
Molecular / Cytogenetics Description
Differential Diagnosis