Introduction of Microwave Ablation Into a Renal Ablation Practice: Valuable Lessons Learned

Area of Science:

• Urology
• Interventional Radiology
• Oncology

Background:

• Renal masses are common, with clinical stage T1 (cT1) representing early-stage disease.
• Minimally invasive treatments are increasingly preferred for localized renal tumors.
• Percutaneous microwave ablation (MWA) offers a less invasive approach to renal mass treatment.

Purpose of the Study:

• To evaluate the early outcomes of percutaneous microwave ablation (MWA) for clinical stage T1 (cT1) renal masses.
• To assess procedural safety and efficacy in a high-volume ablation practice.
• To determine technical success, local tumor control, survival rates, and complication profiles.

Main Methods:

• Retrospective review of a percutaneous renal ablation registry (2011-2017).
• Included 26 patients with 27 cT1 renal masses treated with MWA.
• Outcome measures included technical success, local tumor progression, survival, and complications (Clavien-Dindo classification).

Main Results:

• 100% technical success rate confirmed by immediate post-ablation imaging.
• No local tumor recurrences observed in 24 patients with follow-up averaging 20.6 months.
• Estimated 3-year progression-free survival (PFS) and cancer-specific survival (CSS) were 96% and 94%, respectively.
• Overall complication rate was 19.2%, with 11.5% experiencing major bleeding or urinary complications (grade III or higher), including one death.

Conclusions:

• Percutaneous MWA is a potentially effective minimally invasive treatment for cT1 renal masses.
• Major bleeding and urinary complications can occur, necessitating careful patient and tumor selection.
• Further research is required to optimize patient selection criteria for renal MWA.