Cryoablation versus Radiofrequency Ablation for Renal Tumor Ablation: Time to Reassess?

Abstract

Of the widely available methods for renal tumor ablation, cryoablation was the first to be assessed in the treatment of renal cell carcinoma (RCC) by using open surgical approaches. Open surgical access was necessary because early cryoprobes were too large for percutaneous application. Initial evaluation of percutaneous approaches to renal tumor ablation in humans included a “treat-and-resect” case reported by Zlotta et al (1) in 1997 and the first case with ablation as the sole planned treatment reported by McGovern et al (2) in 1999. With the advent of percutaneous needle applicators, renal tumor ablation moved to interventional radiology suites with ultrasound (US), computed tomography, and, in some cases, magnetic resonance imaging guidance. With percutaneous cryoprobes available shortly thereafter, the next several years saw expansion of the use of percutaneous image-guided radiofrequency (RF) ablation and cryoablation of renal tumors. Most recently, newer modalities such as microwave (MW) ablation and irreversible electroporation (IRE) have been assessed, and even promoted by some, to treat small tumors. The appeal of percutaneous needle applicators for tumor ablation was the avoidance of surgery in selected patients. Indications for renal tumor ablation include advanced age, multiple comorbid conditions, solitary kidneys, familial syndromes, or multiple sporadic RCC. Early experience with small tumors showed a high technical effectiveness rate with a low recurrence rate over short follow-up intervals (3–5). These early successes led to growing enthusiasm for its use in growing numbers of patients, as documented by a Surveillance, Epidemiology, and End Results database trend evaluation comparing the