Technical Feasibility and Safety of Image-Guided Biphasic Monopolar Pulsed Electric Field Ablation of Metastatic and Primary Malignancies.

PURPOSE: To assess the technical feasibility and safety of image-guided percutaneous biphasic monopolar pulsed electric field (PEF) ablation of primary and metastatic tumors.

METHODS AND METHODS: With IRB approval and HIPAA compliance, this retrospective, single-institution study cohort of 17 patients (mean age: 53.5 years, range: 20 - 94 years) with overall progressive disease underwent 26 PEF ablation procedures for 30 metastatic (90%) and primary (10%) target lesions in the thorax (n=20), abdomen (n=7), and head and neck (n=3). Concurrent systemic therapy was used in 14/17 patients (82%). Follow-up imaging was scheduled for 1, 3, and 6 months after PEF ablation, and target and off-target lesion sizes were recorded. The overall response was assessed by the RECIST 1.1 criteria with imaging immediately before PEF serving as baseline. Adverse events (AEs) were determined by the Society of Interventional Radiology classification.

RESULTS: PEF ablation procedures were well tolerated and technically feasible for all 17 of 17 patients. The mean initial size of the target and off-target tumors were 2.6±1.5 cm (range: 0.4 - 6.9cm) and 2.2±1.1 cm (range: 1.0 - 5.2cm), respectively. Overall, 15/30 (50%) target lesions and 12/24 (50%) off-target lesions were unchanged or decreased in size at the patient's last follow-up. Eight patients had overall stable disease (47%) at the last follow-up. There were nine mild (9/26, 35%) and one moderate (1/26, 4%) AE.

CONCLUSION: All PEF procedures were technically feasible with one moderate AE and stable disease for 47% of patients with a median follow-up period of three months.