Minimally Invasive Image-Guided Percutaneous Irreversible Electroporation of Adrenal Metastases.

Purpose: A single-center retrospective study was performed to evaluate the safety and efficacy of minimally invasive irreversible electroporation (IRE) to treat metastatic adrenal tumors.

Materials and methods: This single-center study, approved by the Institutional Review Board, retrospectively analyzed six patients who underwent image-guided percutaneous IRE for adrenal metastases. Pre-procedural imaging included CT, MRI and/or ¹⁸F-FDG PET-CT scans. Primary outcomes measures included technical success, efficacy and safety, while secondary outcome measures were local progression-free survival (LPFS), distant progression-free survival (DPFS) and overall survival (OS). Follow-up scans were scheduled post-procedure, and data analysis employed Excel, SPSS and R.

Results: Patients had diverse primary tumor origins including renal cell carcinoma (2/6), colorectal carcinoma (1/6), non-small cell lung carcinoma (1/6), leiomyosarcoma (1/6) and urothelial carcinoma (1/6). Adverse events were minimal, with only one grade 1 complication reported. Tumor characteristics revealed tumors close to critical structures, with a median pre-ablation size of 23 mm. Technical success was achieved in all procedures. At first follow-up, one patient had complete response, one patient had partial response of the right adrenal gland and complete response of the left adrenal gland, two patients had partial response and two patients had stable disease. Local tumor progression occurred in two out of seven tumors with a median LPFS of 10.9 months, and distant progression was observed in four out of six patients.

Conclusion: Percutaneous, minimally invasive IRE shows promise as a safe treatment option for unresectable metastatic adrenal tumors, demonstrating potential effectiveness. However, further studies with larger patient cohorts are needed to confirm its safety and efficacy.