SIR 2024
Interventional Oncology
Erica C. Emmons, MD
Independent IR Resident
Stanford University
Financial relationships: Full list of relationships is listed on the CME information page.
Andrew Kesselman, MD
Clinical Assistant Professor
Stanford Medicine
Disclosure information not submitted.
David S. Wang, MD, FSIR
Clinical Associate Professor
Interventional Radiology, Stanford University
Disclosure information not submitted.
Gloria L. Hwang, MD
Clinical Associate Professor
Stanford University Medical Center
Financial relationships: Full list of relationships is listed on the CME information page.
To describe early results of patients who underwent pulsed electric field ablation for treatment of metastatic soft tissue sarcoma (STS).
Materials and methods: A single-center retrospective analysis was performed on 16 patients with metastatic STS who underwent pulsed electric field ablation using the Aliya device (Galvanize, Redwood City, CA) from May through September 2023. Response Evaluation Criteria in Solid Tumors 1.1 were used to determine the outcomes.
Results:
Fifteen of 16 patients underwent ablation of tumors with subtotal intent. Ablations sites included lungs (N=9), abdominal/pelvic soft tissue (N=3), pleura/mediastinum (N=2), neck (N=1), and combined liver and retroperitoneal (N=1). Mean number of lesions treated per patient was 1.7 (range 1 to 3). Mean largest tumor dimension was 6.3 cm (range 0.6 to 20.7). Mean number of cycles (defined as 100 pulses) performed was 7.9 (range 3 to 16). Mean lines of chemotherapy prior to ablation was 2.6 (range 0 to 7). Thirteen patients were on concurrent therapy at the time of treatment: chemotherapy (N=2), immunotherapy (N=3), other systemic therapy (N=6), or a combination of therapies (N=2). Six patients had imaging follow-up following ablation; mean interval to follow-up imaging was 48 days (range 19 to 112 days). All patients with follow-up imaging demonstrated SD. Intraprocedural complications included pneumothorax requiring chest tube (N=6) and small amount of blood in the gallbladder (N=1). One patient demonstrated imaging evolution of his mass, with development of a thick hypervascular rind and decreased attenuation centrally on follow-up.
Conclusion:
Pulsed electric field ablation is feasible and safe in patients with metastatic soft tissue sarcoma. Treatment of lung lesions resulted in a relatively high pneumothorax rate compared to other ablation modalities (6 of 9 patients, 67%). Because of the small ablation zones and the relatively large size of the tumors, most treatments were performed with subtotal intent. Short-term follow-up demonstrated stable disease, and further follow-up is required to determine efficacy of local and distant tumor reduction in this patient population.