Recurrent Colorectal Liver Metastases in the Liver Remnant After Major Liver Surgery—IRE as a Salvage Local Treatment When Resection and Thermal Ablation are Unsuitable

Abstract

Purpose To examine the safety and short-term oncologic outcomes of computer-tomography-guided (CT-guided) irreversible electroporation (IRE) of recurrent, irresectable colorectal liver metastases (CRLM) after major hepatectomy deemed unsuitable for thermal ablation. Patients and Methods Twenty-three patients undergoing CT-guided IRE of recurrent CRLM after major hepatectomy were included in this study. All tumors were located adjacent to sole remaining intrahepatic blood vessels and bile ducts, precluding thermal ablation. Patients underwent systematic clinical and imaging follow-up, including magnetic resonance imaging of the liver at 1-month and 3-month intervals thereafter. Time to local and intrahepatic tumor progression within 12 and 36 months and associated risk factors were assessed using Kaplan Meier and Cox regression analysis, respectively. Results Complete ablation with a safety margin of at least 0.5 cm was achieved in 22/23 (95.6%) patients. No vessel injury or thrombosis occurred. Five patients developed moderate biliary stenosis after a median of 4 weeks, without requiring treatment. Local tumor-progression-free rates within 12/36 months were 64%/57.4%, respectively. Intrahepatic-progression-free rate within 12/36 months was 36.4%/19.5%, respectively. Five (23%) patients were tumor-free at the end of follow-up. Multivariate Cox regression analysis did not show any association between local tumor-progression-free rates and patient age, target tumor size, primary tumor side or synchronicity of liver metastases. Conclusion In this highly selected patient population with local recurrences of CRLM after major surgery, IRE was shown to be a safe salvage treatment option when thermal ablation is unsuitable.

Survival after combined resection and ablation is not inferior to that after resection alone, in patients with four or more colorectal liver metastases

“…In general, oncological results after RFA / MWA are continuously improving and the two modalities are similar in terms of local disease control [ 8 ]. More data is required concerning the role and efficacy of IRE in CRLM, which is promising, especially in cases where thermal ablation is contraindicated [ 7 ]. In any case, LAT presents a viable treatment option, particularly for metastases in unfavorable localizations, as its parenchyma-sparing properties allow for re-resection or re-ablation of recurrences [ 7 , 43 ].…”

“…More data is required concerning the role and efficacy of IRE in CRLM, which is promising, especially in cases where thermal ablation is contraindicated [ 7 ]. In any case, LAT presents a viable treatment option, particularly for metastases in unfavorable localizations, as its parenchyma-sparing properties allow for re-resection or re-ablation of recurrences [ 7 , 43 ]. Further studies are warranted, especially prospective, multicentric RCT.…”

“…Local ablative therapy (LAT) plays an increasingly important role in the management of CRLM, as an adjunct to resection or standalone treatment [ 5 , 6 ]. Common modalities include radiofrequency ablation (RFA), microwave ablation (MWA) and irreversible electroporation (IRE) [ 5 – 7 ], and can be conducted intraoperatively or percutaneously [ 3 , 6 – 8 ]. Technological advancements and accumulated experience have resulted in ever-improving results [ 7 , 8 ], so that LAT is now included in official guidelines for multimodal therapy of CRLM [ 3 , 9 ].…”

“…Common modalities include radiofrequency ablation (RFA), microwave ablation (MWA) and irreversible electroporation (IRE) [ 5 – 7 ], and can be conducted intraoperatively or percutaneously [ 3 , 6 – 8 ]. Technological advancements and accumulated experience have resulted in ever-improving results [ 7 , 8 ], so that LAT is now included in official guidelines for multimodal therapy of CRLM [ 3 , 9 ]. However, evidence on the efficacy of LAT compared to resection remains limited and heterogeneous [ 6 , 9 ], partly because studies have focused on LAT of irresectable lesions, with inherent bias regarding long-term outcomes [ 6 , 10 ].…”

Pancreatic islets implanted in an irreversible electroporation generated extracellular matrix in the liver

“… 15 , 16 The extracellular matrix within the treated volume remains intact and blood vessels remain patent. 14 , 17 Accordingly, NTIRE has been used to ablate solid tumors near sensitive body structures, such as large blood vessels within the liver 18 and pancreas. 19 Large blood vessels in the NTIRE-treated region remain intact; the blood vessels do not leak and the endothelial layer regenerates.…”