Safety and feasibility of electrochemotherapy in patients with unresectable colorectal liver metastases: A pilot study.

BACKGROUND AND OBJECTIVES

Electrochemotherapy is a novel ablation technique combining chemotherapeutic agents with reversible cell membrane electroporation. Previous experiences have shown its efficacy for cutaneous tumors. Its application for deep-seated malignancies is under investigation. We performed a prospective, pilot study to evaluate the feasibility, safety, and efficacy of intraoperative electrochemotherapy for otherwise unresectable colorectal liver metastases.

METHODS

Electrochemotherapy with bleomycin was combined with open liver resection and performed with linear or hexagonal needle electrodes according to an individualized pretreatment plan. The primary endpoints were: feasibility, as ratio of completed to planned treatments; safety, and efficacy, as per response assessed at 30 days with MRI and according to RECIST. The secondary endpoint was overall and progression-free survival at month 6.

RESULTS

A total of 9 colorectal liver metastases were treated in 5 patients with 20 electrode applications. No intraoperative complications were observed. At day 30, complete response was 55.5% and stable disease 45.5%. All (5) patients reached a 6 months overall survival, and 4 out of 5 patients had 6 months progression free survival.

CONCLUSIONS

Electrochemotherapy is a feasible and safe adjunct to open surgery for treatment of unresectable colorectal liver metastases. Larger studies and longer follow-ups are favored to better define its role in the treatment of secondary liver malignancies.