A. Veltri¹, A. Calvo¹, A.F. Genovesio¹, P. Sacchetto¹, P. Caggiula¹, C. Gazzera¹, G. Gandini²; ¹Torino/IT, ²Turin/IT

Purpose
To statistically analyse mid-term results of US-guided percutaneous radiofrequency ablation (RFA) of primary renal tumors, in order to identify predictors for complications and technical success

Material and methods
Forty-four primary renal tumors up to 5 cm in diameter (14-50 mm; median 25) in 31 patients (24 with sporadic, 7 with hereditary tumor; 15 single-kidney) were selected out of our 37 consecutive patients series. Complications and mid-term local results (median follow-up time 19 months) were statistically evaluated by possible predictors

Results
Eight adverse events occurred; 3 (6.8%) were major complications, successfully treated with interventional radiology procedures in 2 cases. Exophytic extension of the tumor resulted protective against complications (p=.040). Local success was obtained in 38 lesions after the first RFA and in 39 (88,6%) after a further treatment. The only negative predictor for technical success turned out to be central extension (p=.007); neither exophytic extension, diameter <3 cm (p=.091), nor other variables achieved statistical significance

Conclusion
US-guided percutaneous RFA may be suggest to treat primary non-central renal tumor up to 5 cm in size, also in patients without surgical contraindications, because of its low complication and high technical success rates. Randomized controlled studies versus conservative resection are now necessary to investigate comparative results