Computed tomography guided microwave ablation for the treatment of clinical T1a renal cell carcinoma: a comparison to robot-assisted laparoscopic partial nephrectomy.

purposeTo compare computed tomography guided microwave ablation (MW) and Robot-assisted laparoscopic partial nephrectomy (RAPN) for the treatment of T1a renal cell carcinoma (RCC).

methodRetrospective study including patients treated for clinical T1a RCC with either MW or RAPN.

resultsIn total, 71 patients were planned to MW, and 372 patients to RAPN. Patients undergoing MW were older, more comorbid, and had worse kidney function. The median follow-up was 2.4 years (95% CI 2.0, 3.4) and 3.7 years (95% CI 3.1, 4.0) for MW and RAPN, respectively. 6% of patients who underwent MW experienced a major (Clavien Dindo ≥ III) complication compared to 5% following RAPN. In uni- and multivariable logistic regression analyses, there was no significant difference in the risk of experiencing any or a major postoperative complication. The 5-year cumulative incidence of any recurrence was 10% for MW versus 4% for RAPN. The 5-year incidence of a distant recurrence was 0% for MW and 2% for RAPN, respectively. In univariable Cox regression analyses, patients treated with MW had a higher risk of experiencing any recurrence and a local recurrence compared to those who underwent RAPN, HR 4.24 (95% CI 1.26-14.4) for any recurrence and HR 6.95 (95% CI 1.83-26.4) for a local recurrence, respectively. There was no difference in the risk of a distant recurrence between treatment strategies.

conclusionThese results indicate that MW has an acceptable safety profile and oncological results, and as such is a feasible treatment option for patients with T1a RCC who are poor surgical candidates.