MRI characteristics associated with high-grade myxoid liposarcoma.

Area of Science:

• Radiology and Oncology
• Medical Imaging
• Soft Tissue Tumors

Background:

• Myxoid liposarcoma (LPS) is a soft tissue sarcoma with varying grades.
• Differentiating high-grade LPS from low-grade LPS is crucial for treatment planning.
• Magnetic resonance imaging (MRI) may offer features to distinguish between LPS grades.

Purpose of the Study:

• To identify specific MRI features that differentiate high-grade (>5% round-cell component) from low-grade LPS (≤5% round-cell component).

Main Methods:

• Retrospective analysis of MRI scans from 31 patients with myxoid LPS.
• Radiologists evaluated tumor size, location, tissue layer, and MRI characteristics.
• Statistical analysis, including logistic regression, identified predictors of high-grade LPS.

Main Results:

• A tumor size of ≥10 cm was the strongest independent predictor of high-grade LPS (OR, 14.6).
• High-grade lesions commonly showed lipid signal, a peritumoural capsule, and peritumoural contrast enhancement.
• Heterogeneous signal intensity was more frequent in high-grade tumors.

Conclusions:

• Tumor size ≥10 cm is significantly associated with high-grade myxoid LPS.
• MRI features such as lesion margin, lipid signal, and perilesional characteristics may aid in differentiating LPS grades.