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Updated: Jul 4, 2026
08:07
Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
Published on: April 12, 2019
Aggressive (epithelioid) osteoblastoma arising in soft tissue
Andrea T Deyrup1, David K Monson, Howard D Dorfman
1Department of Pathology, Emory University Atlanta, GA 30308, USA. adeyrup@emory.edu
International Journal of Surgical Pathology
|June 25, 2008
Summary
Aggressive epithelioid osteoblastoma, a rare benign bone tumor, has been identified in soft tissue for the first time. This finding is crucial for distinguishing it from malignant extraskeletal osteosarcoma.
Area of Science:
- Orthopedic Pathology
- Skeletal Tumors
- Soft Tissue Neoplasms
Background:
- Osteoblastoma is a rare, benign bone-forming tumor.
- Epithelioid osteoblastoma is a rare variant of osteoblastoma.
- Extraskeletal osteosarcoma is a malignant soft tissue tumor.
Observation:
- A case of aggressive epithelioid osteoblastoma arising in soft tissue is described.
- The tumor occurred in the axilla of a 21-year-old man.
- The tumor arose in a focus of heterotopic ossification.
Findings:
- This represents the first reported instance of aggressive epithelioid osteoblastoma in soft tissue.
- The tumor exhibited benign histological features of osteoblastoma.
- The tumor demonstrated locally aggressive behavior.
Implications:
- Accurate differentiation between benign aggressive epithelioid osteoblastoma and extraskeletal osteosarcoma is critical for appropriate patient management.
- This case expands the known clinicopathological spectrum of osteoblastoma.
- Further research is needed to understand the behavior and treatment of soft tissue osteoblastoma.
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