A prospective Phase 2a pilot study investigating focal percutaneous irreversible electroporation (IRE) ablation by NanoKnife in patients with localised renal cell carcinoma (RCC) with delayed interval tumour resection (IRENE trial).

INTRODUCTION: Focal ablation therapy is playing an increasing role in oncology and may reduce the toxicity of current surgical treatments while achieving adequate oncological benefit. Irreversible electroporation (IRE) has been proposed to be tissue-selective with potential advantages compared with current thermal-ablation technologies or radiotherapy. The aim of this pilot trial is to determine the effectiveness and feasibility of focal percutaneous IRE in patients with localised renal cell cancer as a uro-oncological tumour model.

METHODS: Prospective, monocentric Phase 2a pilot study following current recommendations, including those of the International Working Group on Image-Guided Tumor Ablation. Twenty patients with kidney tumour (T1aN0M0) will be recruited. This sample permits an appropriate evaluation of the feasibility and effectiveness of image-guided percutaneous IRE ablation of locally confined kidney tumours as well as functional outcomes. Percutaneous biopsy for histopathology will be performed before IRE, with magnetic-resonance imaging one day before and 2, 7, 27 and 112 days after IRE; at 28 days after IRE the tumour region will be completely resected and analysed by ultra-thin-layer histology.

DISCUSSION: The IRENE study will investigate over a short-term observation period (by magnetic-resonance imaging, post-resection histology and assessment of technical feasibility) whether focal IRE, as a new ablation procedure for soft tissue, is feasible as a percutaneous, tissue-sparing method for complete ablation and cure of localised kidney tumours. Results from the kidney-tumour model can provide guidance for designing an effectiveness and feasibility trial to assess this new ablative technology, particularly in uro-oncology.