Colorectal liver metastases: making the unresectable resectable using irreversible electroporation for microscopic positive margins – a case report

Irreversible electroporation (IRE) is a non-thermal injury tissue ablation technique that uses electrical pulses to cause cell death. IRE damages the endothelial cells of blood vessels; however these cells re-grow, and thus IRE does not result in permanent damage to blood vessels. We report the novel use of IRE for ablation of microscopically positive margins after resection of colorectal liver metastases (CRLM) impinging on hepatic veins.

A 68-year-old female was found to have colon cancer and synchronous bilateral unresectable liver metastases. Chemotherapy with FOLFOX and cetuximab was initiated, with subsequent conversion to resectability of the CRLM. The patient underwent colectomy followed by right liver posterior sectionectomy with wedge resection of segment 5. Resection of tumor impinging on the left and middle hepatic veins would have required left hepatectomy, with insufficient remnant liver volume. The CRLM were meticulously dissected off the hepatic veins leaving a microscopically positive margin, and IRE was then used for margin ablation, leaving intact hepatic veins and venous blood flow. The patient is alive and without recurrent disease now 30 months after resection. Herein we review the IRE technology and its use in ablation of liver metastases.

Use of IRE margin ablation for microscopically-positive CRLM resection may lead to long-term patient survival; further prospective randomized trials are needed to confirm this finding.