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Updated: May 24, 2026
Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
Published on: April 12, 2019
Correlation of non-mass-like abnormal MR signal intensity with pathological findings surrounding pediatric
Karim Z Masrouha1, Khaled M Musallam, Alexis Bou Samra
1Department of Surgery, American University of Beirut Medical Center, PO Box 11-0236, Riad El Solh, Beirut 1107 2020, Beirut, Lebanon. km34@aub.edu.lb
Objective:
The aim of this work was to determine the role of MRI in interpreting abnormal signals within bones and soft tissues adjacent to tumor bulk of osteosarcoma and Ewing's sarcoma in a pediatric population by correlating MR findings with histopathology.
Materials And Methods:
Thirty patients met the inclusion criteria, which included (1) osteosarcoma or Ewing's sarcoma, (2) MR studies no more than 2 months prior to surgery, (3) presence of abnormal MR signal surrounding the tumor bulk, (4) pathological material from resected tumor. The patients received standard neoadjuvant chemotherapy. Using grid maps on gross pathology specimens, the abnormal MR areas around the tumor were matched with the corresponding grid sections. Histopathology slides of these sections were then analyzed to determine the nature of the regions of interest. The MR/pathological correlation was evaluated using Mann-Whitney U test and Fisher's exact test.
Results:
Twenty-seven patients had osteosarcoma and three patients had Ewing's sarcoma. Of the studied areas, 17.4% were positive for tumor (viable or necrotic). There was no statistically significant correlation between areas positive for tumor and age, gender, signal extent and intensity on MRI, or tissue type. There was, however, a statistically significant correlation between presence of tumor and the appearance of abnormal soft tissue signals. A feathery appearance correlated with tumor-negative areas whereas a bulky appearance correlated with tumor-positive regions.
Conclusions:
MR imaging is helpful in identifying the nature of abnormal signal areas surrounding bone sarcomas that are more likely to be tumor-free, particularly when the signal in the soft tissues surrounding the tumor is feathery and edema-like in appearance.
Insights
Magnetic resonance imaging (MRI) helps differentiate tumor-free areas from tumor-positive regions in pediatric bone sarcomas. A feathery soft tissue signal on MRI suggests tumor-free areas, aiding surgical planning.
Area of Science:
- Pediatric oncology
- Radiology
- Surgical pathology
Background:
- Accurate interpretation of imaging findings adjacent to bone sarcomas is crucial for pediatric oncology.
- Distinguishing tumor margins from reactive changes in osteosarcoma and Ewing's sarcoma can be challenging.
- Magnetic resonance imaging (MRI) is a key modality for evaluating soft tissue involvement.
Purpose of the Study:
- To evaluate the role of MRI in characterizing abnormal signals in bone and soft tissues surrounding pediatric osteosarcoma and Ewing's sarcoma.
- To correlate MRI findings with histopathology to determine the nature of peritumoral signals.
- To assess the utility of MRI in differentiating tumor-involved from tumor-free areas.
Main Methods:
- Retrospective analysis of MRI studies from 30 pediatric patients with osteosarcoma or Ewing's sarcoma.
- Correlation of pre-operative MRI findings with post-operative histopathology of resected tumor specimens.
- Use of grid maps to match MRI signal areas with corresponding pathological sections.
- Statistical evaluation using Mann-Whitney U test and Fisher's exact test.
Main Results:
- Seventeen percent of studied areas were positive for viable or necrotic tumor.
- No significant correlation found between tumor presence and patient age, gender, MRI signal extent/intensity, or tissue type.
- Abnormal soft tissue signals on MRI showed a statistically significant correlation with tumor presence.
- A feathery soft tissue signal appearance correlated with tumor-negative areas, while a bulky appearance correlated with tumor-positive regions.
Conclusions:
- MRI is valuable in identifying peritumoral areas that are likely tumor-free in pediatric bone sarcomas.
- Feathery and edema-like soft tissue signals on MRI are indicative of tumor-free regions.
- MRI findings can assist in surgical planning by improving the characterization of tumor margins.
