Percutaneous microwave ablation of HCC: comparison between 100 and 150 W technology systems

Purpose To evaluate the differences in efficacy and safety between the 100 and 150 W percutaneous microwave ablation (MWA) systems in the treatment of hepatocellular carcinoma (HCC). Methods We retrospectively reviewed all patients who underwent percutaneous MWA (Emprint (TM) HP Ablation System, Medtronic) between January 2021 and May 2023. We divided the cohort into two groups: Group 1, treated with MWA at 100 W power system, and Group 2, treated with 150 W one. Effectiveness was defined as the absence of residual disease at 1-month CT follow-up; safety was defined as the absence of grade II-VI complications. Results A total of 135 HCC nodules were treated with MWA in 87 patients with a median age of 66 +/- 10 years: 76 procedures in 42 patients were carried out in group 1, while 59 procedures in 45 patients in group 2. Cases treated with 150 W had a shorter ablation time (p: 0.002; mean 227.37 +/- 92.5 vs 180.51 +/- 75.6 s (100 vs 150 W)) and a larger ablation volume (p 0.008; mean 13,920.0 +/- 10,723.2 vs 21,241.4 +/- 18,374.7 mm(3) (100 vs 150 W)), and a major effectiveness at 1-month CT follow-up (p: 0.013). A higher rate of complications (grade II and III) was observed in Group 2 (p < 0.001). Conclusions In conclusion, these preliminary results showed a good correlation between intended-to-treat area and ablation volume and intended-to-treat area and ablation time for both Groups. A minor ablation time, and major ablation volume, but also a higher incidence of complications was observed in 150 W Group.