Bone & joints
Undifferentiated small round cell sarcoma of bone and soft tissue
Undifferentiated pleomorphic sarcoma
Author: Nat Pernick, M.D.
Last author update: 1 June 2005
Last staff update: 15 September 2023 (update in progress)
Copyright: 2003-2023, PathologyOutlines.com, Inc.
PubMed search: malignant fibrous histiocytoma [title] bone
Table of Contents
Definition / general | Radiology images | Gross images | Microscopic (histologic) imagesCite this page: Pernick N Undifferentiated pleomorphic sarcoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/boneMFH.html. Accessed September 28th, 2023.
Definition / general
- Mean age 34 - 40 years but all ages, no gender predominance
- Sites: metaphysis of long bones, jaw
- Associated with bone infarcts (30%), foreign bodies, radiation (15%), Paget disease, dedifferentiation or transformation of chondrosarcoma, chordoma or giant cell tumor (Am J Surg Pathol 1986;10:9)
- Behaves like a high grade sarcoma with a poor prognosis, particularly for older patients and secondary sarcomas
- Five year survival of 78% if prominent chronic inflammatory infiltrate
Radiology images
Contributed by AFIP images and Mark R. Wick, M.D.
Radiograph of tibial tumor
Primary, distal femur
Gross images
Contributed by Mark R. Wick, M.D.
Primary
Microscopic (histologic) images
Contributed by AFIP images and Mark R. Wick, M.D.
Mixture of malignant fibroblasts and histiocytes
Fibroblasts dominate
Irregular deposits of noncalcified collagen
Broad area of collagen deposits is sparsely cellular
Markedly vascular tumor
Various images
