Clinical impact of irreversible electroporation ablation for unresectable hilar cholangiocarcinoma.

Irreversible electroporation (IRE) is a non-thermal ablation modality that has been shown to be safe and effective in its application to tumors that are close to risky areas. This study aims to assess the safety and efficacy of IRE for unresectable hilar cholangiocarcinoma. Nine patients from two medical centers in Asia received IRE treatment between June 2015 and July 2017. Before IRE treatment, percutaneous biliary decompressions had been performed on eight patients, and internal stenting had been performed on one patient. All patients tolerated the procedure well without high-grade complications. The ablated tumors had constant size without contrast enhancement for more than three months in eight patients and the level of CA19-9 decreased significantly in all patients. The percutaneous biliary drainage tube was removed from two patients with recanalization of the bile duct. The internal stent in one patient was removed without further stenting. The median overall survival period was 26 months, and the progression-free survival was 18 months. Bile ducts remained narrow in the majority (2/3) of the treated patients. Nevertheless, IRE ablation of unresectable hilar cholangiocarcinoma involving vital structures is a safe and feasible primary treatment for local tumor control and is effective in prolonging survival.