High-Intensity Focused Ultrasound Ablation for Soft Tissue Tumors in Challenging Anatomical Locations: Preliminary Study.

OBJECTIVE

This study aimed to evaluate the feasibility, safety, and preliminary efficacy of high-intensity focused ultrasound (HIFU) ablation for treating soft tissue tumors (STTs) located in challenging anatomical regions (e.g. adjacent to critical nerves, blood vessels, joint areas, or recurrent tumors).

MATERIALS AND

METHODS

A retrospective analysis was conducted on 11 patients with locally unresectable recurrent STTs treated with under ultrasound-guided HIFU from January 2024 to December 2024. The cohort included recurrent desmoid tumors (3 cases) and other complex soft tissue sarcomas (8 cases), all histologically confirmed. Tumor locations encompassed intra-abdominal, abdominal wall, chest wall, extremities, scapular region, and pelvic region. Treatment efficacy was assessed via ablation volume, adverse events (graded by CTCAE v5.0), and imaging follow-up (contrast-enhanced MRI/CT).

RESULTS

All patients underwent successful HIFU treatment, targeting 18 tumor lesions. The median non-perfusion volume ratio (NPVR) post-HIFU was 93.24%. At 3-month follow-up, 12 lesions exhibited significant shrinkage, while 6 remained stable. Mild adverse events included transient skin edema, mild pain, and orange-peel-like skin changes (case 3).

CONCLUSION

As a noninvasive modality, HIFU demonstrated favorable local control and safety in managing STTs in challenging locations. For surgically high risk or recurrent lesions, HIFU effectively controlled tumor progression and improved extremity function.