摘要Background:Balloon catheter isolation is a promising auxiliary method for thermal ablation treatment of liver cancer.We aimed to explore the safety and effectiveness of balloon catheter isolation-assisted ultrasound-guided percutaneous microwave ablation(MWA)in treating liver cancer in difficult anatomical locations.Methods:Data of 132 patients with 145 difficult-site liver cancer treated with ultrasound-guided per-cutaneous MWA were retrospectively analyzed.Participants were classified into the isolation(n=40)and non-isolation(n=92)groups based on whether the patients were treated using a balloon catheter prior to ablation.The major complication rates,local tumor residuals(LTR),and tumor follow-up for local tumor progression(LTP)at 6 and 12 months post-ablation were compared between the two groups.Results:The rates of major postoperative complications did not significantly differ between the isola-tion and non-isolation groups(2.5％vs.4.3％,P=0.609).The postoperative LTR rates were significantly different between the isolation and non-isolation groups(4.8％vs.17.5％,P=0.032).Balloon catheter iso-lation[odds ratio(OR)=0.225,95％confidence interval(CI):0.085-0.595,P=0.009]and tumor diameter(OR=2.808,95％CI:1.186-6.647,P=0.019)were identified as independent factors influencing LTR rate.The cumulative LTP rates at 6 and 12 months after ablation showed no significant differences between the isolation and non-isolation groups(2.6％vs.7.9％,P=0.661;4.9％vs.9.8％,P=0.676,respectively).Cox proportional hazards regression analysis showed that tumor diameter was an independent risk factor for cumulative LTP rate(OR=3.445,95％CI:1.406-8.437,P=0.017).Conclusions:Balloon catheter isolation-assisted MWA was safe and effective in the treatment of difficult-site liver cancer.Additionally,tumor diameter significantly influenced LTR and LTP rates after ablation.