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Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
Published on: April 12, 2019
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Low-grade central osteosarcoma with extraosseous dedifferentiation: a rare case
Kengo Kawaguchi1,2, Kenichi Kohashi1, Koji Sagiyama3
1Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-Ku, Fukuoka, 812-8582, Japan.
Skeletal Radiology
|March 12, 2024
Summary
Low-grade central osteosarcoma (LGCOS) rarely presents with a dedifferentiated component. This case highlights LGCOS with an extraosseous dedifferentiated lesion, showing genetic alterations linked to malignant transformation.
Area of Science:
- Oncology
- Orthopedic Oncology
- Skeletal Pathology
Background:
- Low-grade central osteosarcoma (LGCOS) originates in the long bone metaphysis.
- Extraosseous spread and dedifferentiation are uncommon in LGCOS.
- Dedifferentiated components typically arise separately, not as part of the primary tumor.
Observation:
- A 38-year-old female presented with knee pain and imaging revealed a bone mass with extraosseous involvement.
- Pathologic examination confirmed LGCOS with a dedifferentiated extraosseous component.
- A cortical defect separated the low-grade and high-grade tumor areas.
Findings:
- The extraosseous high-grade component showed increased p53 overexpression and MDM2 gene amplification compared to the low-grade component.
- Genetic mutations and copy number alterations were identified.
- These molecular changes may drive malignant progression.
Implications:
- This case expands the understanding of LGCOS presentation and behavior.
- It suggests that LGCOS can undergo malignant transformation with dedifferentiation.
- Further research into the genetic drivers of LGCOS dedifferentiation is warranted.
