Mediastinum
Soft tissue lesions
Malignant peripheral nerve sheath tumor (MPNST)


Topic Completed: 1 December 2012

Revised: 4 December 2019

Copyright: 2003-2019, PathologyOutlines.com, Inc.

PubMed Search: Malignant peripheral nerve sheath tumor mediastinum[TI]

Hanni Gulwani, M.B.B.S.
Page views in 2019: 403
Page views in 2020 to date: 76
Cite this page: Gulwani H. Malignant peripheral nerve sheath tumor (MPNST). PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/mediastinumMPNST.html. Accessed February 27th, 2020.
Clinical features
  • Often associated with neurofibromatosis
  • 4% of MPNST show perineurial cell differentiation (Am J Surg Pathol 1998;22:1368)
  • Often spreads to pleura or lungs
Prognostic factors
  • Extremely poor prognosis if glandular or rhabdomyosarcomatous features
Case reports
Gross description
  • Unencapsulated, degenerative changes common (fat, hemorrhage, cysts)
Microscopic (histologic) description
  • Bizarre cells and tumor giant cells
  • Also atypical mitotic figures and necrosis
  • May have areas of uniform bland spindle cells
  • Rarely has rhabdomyosarcomatous features ("triton tumor") or glandular differentiation
Microscopic (histologic) images

Images hosted on other servers:

Low grade tumor has
increased cellularity,
nuclear atypia, scattered
mitotic figures

Fascicular proliferation of atypical spindle cells

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