Thermal Ablation of Renal Tumors: Indications, Techniques and Results

BACKGROUND: About 15,000 persons receive the diagnosis of kidney cancer in Germany every year. Surgical resection is the standard treatment for locally confined tumors, but minimally invasive thermoablative techniques are increasingly being used as well.

METHODS: This article is based on publications retrieved by a selective literature search in PubMed regarding the thermoablative techniques now used in clinical practice, with particular attention to radiofrequency ablation (RFA) and cryoablation (CA).

RESULTS: RFA and CA are suitable for patients who cannot undergo surgery because of comorbid illnesses or who have contralateral recurrences or a hereditary precancerous condition. The primary technical success rate of these procedures ranges from 88% to 100%. More than 95% of tumors under 3 cm in diameter can be completely ablated. Reported complication rates range from 1% to 7%. New data on long-term outcomes reveal metastasis-free survival rates of 88% to 99% five years after ablation. A major advantage of these procedures is that thermoablation does not impair renal function to any relevant extent and is thus a good option for patients with limited renal function or a single kidney.

CONCLUSION: The thermoablative techniques are an important addition to the armamentarium of effective treatments for locally confined renal tumors. The guidelines of the American and European urological societies now list thermoablation with RFA or CA as an option for the treatment of small renal tumors with curative intent. Thermoablation of renal tumors has not yet been studied in randomized controlled trials; these will be needed so that the efficacy of tumor control, survival rates, complication rates, and quality of life after treatment can be reliably evaluated to provide definitive confirmation of the value of interstitial techniques.