Uterus
Stromal tumors
Sarcoma NOS

Author: Mohamed Desouki, M.D. (see Authors page)

Revised: 3 February 2017, last major update September 2011

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

PubMed search: sarcoma NOS

Cite this page: Sarcoma NOS. PathologyOutlines.com website. http://pathologyoutlines.com/topic/uterussarcoma.html. Accessed June 24th, 2017.
Definition / general
  • Rare tumors that display pleomorphic cells with high mitotic index that show no evidence of stromal or smooth muscle derivation
  • Considered to be variants of MMMT, but without an epithelial component and lacking endometrial stromal features
  • Must sample thoroughly to rule out MMMT
  • Poor prognosis
Terminology
  • Undifferentiated uterine or endometrial sarcoma
Epidemiology
  • Average age 45 years, present with vaginal bleeding
Case reports
Treatment
  • No consistent data available
Gross description
  • Necrotic fleshy, bulky tumor fills uterine cavity with polypoid appearance usually with deep myometrial invasion
Microscopic (histologic) description
  • Marked nuclear anaplasia, variable pleomorphism, 20+ mitotic figures/10 HPF
  • Large round, spindle or bizarre cells; chromatin is coarse, clumped with large prominent nucleoli
  • Extensive necrosis is a common feature
  • Entrapped glands usually small, inconspicuous, not surrounded by condensed stroma as in adenosarcoma
Microscopic (histologic) images

Images hosted on PathOut server:

Undifferentiated sar-
coma of endometrium -
pleomorphic giant and
spindle cells

Undifferentiated sarcoma of endo-
metrium - poorly differentiated
spindled cells, numerous mitoses,
necrosis at lower right

Negative stains
Differential diagnosis