High-grade soft-tissue sarcoma: optimizing injection improves MRI evaluation of tumor response

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Neoadjuvant chemotherapy (NAC) is crucial for locally advanced high-grade soft-tissue sarcomas (STS).
• Accurate assessment of treatment response is vital for patient management.
• Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) shows promise in evaluating tumor response.

Purpose of the Study:

• To identify the optimal acquisition delay after gadolinium-chelate injection for DCE-MRI.
• To enhance the prediction of histological response to anthracycline-based NAC in STS.
• To improve the accuracy of response assessment criteria like the Choi criteria.

Main Methods:

• Thirty patients with locally advanced high-grade STS undergoing NAC were studied.
• DCE-MRI was performed before and after two cycles of NAC.
• Change in contrast enhancement (CE) was analyzed at various acquisition delays post-injection.
• Area under the receiver-operating characteristics curves (AUROC) and Choi criteria accuracy were calculated.

Main Results:

• Acquisition delay significantly impacted CE change and response prediction (p=0.0014 and p=0.0270).
• The highest AUROC (0.792) was achieved at a 58-second delay, with an optimal threshold of -30.5% CE decrease.
• At 58 seconds, prediction accuracy for poor response was 82.8%, outperforming Choi criteria (72.4%) and RECIST 1.1 (70%).

Conclusions:

• Optimizing acquisition delay in DCE-MRI enhances the prediction of histological response to NAC in STS.
• A 60-second acquisition delay is recommended for improved evaluation of tumor response and accuracy of the Choi criteria.
• DCE-MRI facilitates the determination of optimal imaging parameters for response assessment in STS.