[Interventional oncology in urology].

Partly because of its rising incidence, but mostly because of the availability of modern examination techniques, the detection rate of small renal-cell carcinomas is increasing more and more. Even though tumors exceeding 4 cm in diameter rarely metastasize, all renal lesions that arouse the suspicion of malignancy should be treated. Operative treatment techniques such as radical and partial nephrectomy are increasingly carried out as laparoscopic procedures and are regarded as the gold standard. Modern thermal ablation techniques may be a helpful treatment option for patients who are unfit for a surgical resection or refuse it. Radiofrequency ablation (RFA) is the most frequently applied of these methods. Modern probes allow ablation of lesions between 2 and 5 cm in diameter. In the vast majority of cases RFA is carried out percutaneously and monitored by ultrasound or CT; it is deemed safe and the complication rate is low. While randomized comparative studies against open resection are yet available, the preliminary results obtained with renal RFA are promising and suggest that RFA may be superior to other thermal ablation techniques. Clinical success rates are over 90% for radiofrequency, and also for cryotherapy, which is performed less often. Local relapse is very uncommon.