Author: Nat Pernick, M.D. (see Authors page)

Revised: 23 November 2016, last major update June 2005

Copyright: (c) 2003-2016,, Inc.

PubMed search: mesenchymal chondrosarcoma [title] bone

Cite this page: Mesenchymal. website. Accessed September 25th, 2018.
Definition / general
  • Cartilaginous tumor with primitive component composed of mesenchymal cells at condensation stage
  • Rare; usually teenagers or young adults; no significant gender preference
  • Unpredictable prognosis; may have short or prolonged survival after metastases
  • Initial study suggests SOX9 is specific for this tumor versus other small blue cell tumors (Hum Pathol 2003;34:263)
  • Sites: diaphysis of jaw, pelvis, femur, ribs, spine; often involves extraosseous structures such as orbit, paraspinal region, meninges, extremity soft tissue
Radiology description
  • Resembles conventional chondrosarcoma
Radiology images
Images hosted on PathOut server:

Expansile, predominantly lytic lesion

Gross description
  • Pink, fleshy, with calcification
  • Resembles other sarcomas
Gross images
Images hosted on PathOut server:

Distal femur

Microscopic (histologic) description
  • Dimorphic pattern of well differentiated cartilage with abrupt boundary from undifferentiated stroma composed of small round / oval cells resembling lymphoma, hemangiopericytoma or Ewing's sarcoma / PNET
  • Occasional spindle cells
  • Minimal pleomorphism, no / rare mitotic figures
Microscopic (histologic) images
Images hosted on PathOut server:

Contributed by Dr. Mark R. Wick

Neoplastic cells

Low power

Well defined island of low grade cartilage

Tumor cells separated by collagen

Dense cellularity

Positive stains
Negative stains
Molecular / cytogenetics description
  • Translocation der(13;21)(q10:q10) identified in 2 patients with skeletal and extraskeletal tumors (Mod Pathol 2002;15:572)
Differential diagnosis
Additional references