Radiofrequency Ablation, Cryoablation, and Microwave Ablation for the Treatment of Small Renal Masses: Efficacy and Complications

Abstract

Over the last two decades the detection rate of small renal masses has increased, due to improving diagnostic accuracy, and nephron-sparing treatments have become the first-choice curative option for small renal masses. As a minimally invasive alternative, thermal ablation has increased in popularity, offering a good clinical outcome and low recurrence rate. Radiofrequency ablation, Cryoablation, and Microwave ablation are the main ablative techniques. All of them are mostly overlapping in term of cancer specific free survival and outcomes. These techniques require imaging study to assess lesions features and to plan the procedure: US, CT, and both of them together are the leading guidance alternatives. Imaging findings guide the interventional radiologist in assessing the risk of complication and possible residual disease after procedure. The purpose of this review is to compare different ablative modalities and different imaging guides, underlining the effectiveness, outcomes, and complications related to each of them, in order to assist the interventional radiologist in choosing the best option for the patient.

Percutaneous microwave ablation of T1a renal cell carcinomas: A 10‐year single‐center retrospective review

“…They stated a 5-year cancer-specific survival of about 95-98%. 8 MWA also had the benefit of shorter procedural and ablation times compared to the cryoablation and RFA groups. A systematic review and meta-analysis of comparison studies comparing efficacy and safety of MWA against RFA and cryoablation was undertaken by Castellana et al 9 The study included a total of 2258 thermal ablations and concluded that MWA is as effective and safe as RFA and cryoablation in addition to encountering fewer recurrences.…”

“…This was despite the MWA group having a larger median tumour size compared to cryoablation (no difference in local or metastatic recurrence). They stated a 5‐year cancer‐specific survival of about 95–98% 8 . MWA also had the benefit of shorter procedural and ablation times compared to the cryoablation and RFA groups.…”

“…6,7 There have also been a number of systematic reviews, meta-analyses and retrospective cohort studies demonstrating either superior or similar cancer-related outcomes and lower complication rates in MWA for RCCs when compared to RFA and cryoablations. [8][9][10] The RENAL nephrometry score is a system used to describe tumour anatomy and complexity and has been used as a tool to aid perioperative decision-making and to predict long-term outcomes. Using this scoring system, the tumour can be classified into low complexity (score 4-6), moderate complexity (score 7-9) and high complexity (score [10][11][12].…”

“…Its usefulness in clinical practice in regard to renal tumours when comparing MWA to PN has only been demonstrated through retrospective cohort studies 6,7 . There have also been a number of systematic reviews, meta‐analyses and retrospective cohort studies demonstrating either superior or similar cancer‐related outcomes and lower complication rates in MWA for RCCs when compared to RFA and cryoablations 8–10 …”

Percutaneous Ablation of T1 Renal Masses: Comparative Local Control and Complications after Radiofrequency and Cryoablation

“…Indeed, CA is associated with a higher risk of hemorrhage because the surrounding blood arteries are not directly cauterized, such as in RFA, where heat has an intrinsic coagulative effect and reduces the risk of minor hemorrhage. Moreover, CA usually requires the insertion of multiple probes to create an adequate ice ball, and the procedure is longer, resulting in a higher amount of tissue damage [36].…”