Soft tissue
Fibroblastic / myofibroblastic tumors
Nuchal-type and Gardner-associated fibroma

Author: Christine E. Jabcuga, M.D. (see Authors page)
Editor: Jerad M. Gardner, M.D.

Revised: 29 August 2016, last major update June 2013

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

PubMed Search: Nuchal-type fibroma OR Gardner-associated fibroma

Cite this page: Nuchal-type and Gardner-associated fibroma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/softtissuenuchaltypefibroma.html. Accessed December 2nd, 2016.
Definition / General
  • Bundles of thick collagen fibers in posterior neck
  • Also called collagenosis nuchae, nuchal fibrocartilaginous pseudotumor, nuchal fibroma
  • Nuchal: nape (posterior) of neck
  • Related entities: Gardner-associated fibroma (extra-nuchal location but essentially identical histology)
Epidemiology
  • Rare benign lesion of dermis and subcutis in posterior neck (70%), upper back or other regions
  • More common in men, mean age 40 years (age range 3 - 74 years)
  • Associated with diabetes mellitus in 44% (Cancer 1999;85:156)
Case Reports
Treatment
  • Excision, may recur locally but does not metastasize
Gross Description
  • Usually 3 cm or less, hard and white, unencapsulated, poorly circumscribed
Micro Description
  • No capsule, hypocellular, thick collagen fibers with delicate elastic fibers (Am J Surg Pathol 1995;19:313, Stanford University)
  • Entrapped adipose tissue and entrapped nerves (may resemble traumatic neuroma)
  • May infiltrate into skeletal muscle and adipose tissue, may have scattered lymphocytes
Micro Images

Images hosted on PathOut servers:
AFIP images:

Strands of acellular collagen mixed with fat

Lesion is very hypocellular, differentiating it from fibromatosis



Images hosted on other servers:

Figures 2 - 7

Positive Stains
Negative Stains
Differential Diagnosis
  • Elastofibroma: prominent abnormal elastic fibers, subscapular location and often bilateral
  • Fibrolipoma: circumscribed, different location
  • Fibromatosis: deep soft tissue, not back of neck, more cellular with broad fascicles of fibroblasts
  • Gardner fibroma: same histologic features but extra-nuchal location (may be related or identical entity)
  • Solitary fibrous tumor: patternless pattern, more cellular, staghorn type vessels