Radio Frequency (RF) Ablation of Renal Tumours Does Not Produce Complete Tumour Destruction: Results of a Phase II Study

Abstract

Objective: Radio frequency (RF) ablation of small renal tumours has been recently proposed by many urological centres as an alternative treatment to open surgery. However the data on the pathological results on tumour cells after RF are controversial. The objective of this phase II study was to evaluate the pathological changes and the rate of necrosis after intraoperative RF ablation performed immediately before surgery and to observe side effects. Methods: Eight patients with eight renal tumours were treated with RF ablation prior to open surgery. The RITA needle with 9 tines was inserted into the centre of the mass under ultrasound control. The mean patient age was 57.3 years (30–71), the mean tumour diameter was 4.4 cm (2–7.1) and the mean tumour ablation time was 24.7 minutes (18–24). The tissue temperature reached was 100 °C in all but two cases. A hematoxylin-eosin staining protocol was used by pathologists for tumour examination and the rate of tumour necrosis was defined on slides. Results: The final pathological examination revealed tumour necrosis in all the tumours except one, an angiomyolipoma. Coagulative tumour necrosis varied from 15% to 90% of the specimens (mean tumour necrosis rate was 60%). Complications: mild bleeding after the angiomyolipoma treatment. Conclusions: RF ablation was ineffective for total destruction of renal tumours.