Case Report: Pulsed electric field treatment of metastatic liver disease demonstrating a possible abscopal response.

Adrenocortical carcinoma (ACC) is a rare and aggressive endocrine malignancy, typically presenting at an advanced stage with distant metastases. We report a unique case of a 49-year-old female with metastatic ACC in the liver who exhibited an abscopal effect following pulse electric field (PEF) ablation. The patient initially presented with hypertension, male-patterned hair loss, voice hoarseness, and weight gain and was subsequently diagnosed with a large left adrenal mass along with liver and pulmonary metastases. Following surgical interventions-including left salpingo-oophorectomy, hepatic wedge resection, and left adrenalectomy-and initial systemic treatment with doxorubicin, etoposide, and cisplatin-mitotane (EDP-M), disease progression prompted initiating therapy with pembrolizumab and mitotane. The patient then received Y90 treatment in the right lobe; however, imaging demonstrated viable metastatic disease in the left lobe, which prompted PEF treatment. The patient received PEF almost 7 months post-pembrolizumab and mitotane initiation. Remarkably, two months post-PEF treatment, PET/CT imaging demonstrated complete resolution of three of the four untreated lesions, suggesting an abscopal response. This case adds to the limited literature on PEF ablation, highlighting its potential not only as a local control strategy but also as an adjunct to systemic immunotherapy in liver tumors. Further prospective studies incorporating immune profiling are warranted to elucidate the underlying mechanisms and long-term benefits of this approach.