Soft tissue
Smooth muscle
Leiomyoma of deep soft tissue

Author: Vijay Shankar, M.D. (see Authors page)

Revised: 29 September 2016, last major update November 2012

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

PubMed Search: Leiomyoma of deep soft tissue

Cite this page: Leiomyoma of deep soft tissue. website. Accessed October 22nd, 2016.
Definition / General
  • Very rare tumor of deep subcutis or skeletal muscle of extremities (Stanford University) or retroperitoneum (described below)
  • By definition, is distinct from uterus
  • Tumors of deep somatic soft tissue affect males and females equally (Am J Surg Pathol 2001;25:1134)
  • Tumors of retroperitoneum (described below) almost always occur in women
  • Can rarely occur in children
Case Reports
  • Excision; rarely recurs
Clinical Images

Images hosted on other servers:

Hand mass:
intraoperative and
gross specimen

Gross Description
  • Well circumscribed, gray-white
  • Usually large at presentation, up to 15 cm
  • May have myxoid change
Micro Description
  • Fascicles of normal appearing smooth muscle with eosinophilic cytoplasm
  • Nuclei are bland and uniform, blunt ended, cigar shaped
  • May have dystrophic calcification, degenerative nuclear changes or necrobiotic nodules resembling giant rosettes
  • Hyalinization and fatty differentiation can also be seen rarely
  • No / minimal atypia
  • No / rare mitotic figures (Am J Surg Pathol 1994;18:576); < 1 per 50 HPF
  • No necrosis
Cytology Description
  • Hypocellular smears, with scattered clusters of spindle cells (Diagn Cytopathol 1997;16:326)
  • Clustered cells have syncytial appearance
  • Bland nuclei have spindled appearance with rounded ends, condensed chromatin
  • Usually no necrosis or inflammation
  • No mitotic figures
Positive Stains
Negative Stains
Differential Diagnosis