Renal tumor ablation.

Percutaneous, image-guided ablation for renal cell carcinoma (RCC) is an important treatment option for many patients. With more than 60,000 new cases every year and nearly three-fourths of those presenting as stage 1A, minimally invasive, nephron-sparing therapies have become the standard of care. Stage 1 A (<4cm, organ confined) disease presents the best scenario for percutaneous ablation. Various other factors influence the decision-making tree, such as patient age, life expectancy, comorbid condition, renal function, and the risk of metachronous lesions. Preparation aims at minimizing risks and has been discussed in detail. Computed tomography guidance remains the best option, and conscious sedation is adequate for most cases. Ultrasound and more recently magnetic resonance guidance are becoming viable alternatives. Whether radiofrequency or cryoablation are chosen, a margin of at least 5mm and up to 10mm is recommended. Various maneuvers required for optimum outcome, including hydrodissection and preoperative embolization are also discussed. Most renal ablations can be performed on an outpatient basis. Reasons to admit include complications, high-risk patients, and the need for symptom management. Follow-up aims at (1) ensuring complete ablation and (2) monitoring against a metachronous lesion. For the former, a 3-month contrast computed tomography or magnetic resonance imaging is required and for the latter an annual examination is recommended. Though partial nephrectomy remains the gold standard, image-guided, percutaneous ablation for RCC can result in very similar outcomes. Over the last 10 years, there have been numerous studies reporting the efficacy and safety of ablation, and more recently, long-term studies have confirmed those numbers. Overall, the efficacy for percutaneous ablation for RCC stands at 90%-95% with a complication rate of 6%-7%. The most important factors for positive outcome are patient or tumor selection and operator experience.