Abstract:
Objective To assesse the safety and effectiveness of the percutaneous radiofrequency ablation (RFA) of sub diaphragmatic liver tumors.
Methods Seventy-nine out of 138 primary or secondary liver tumor patients underwent percutaneous ultrasonography guided RFA. Overall, 76 nodules were sub diaphragmatic (group 1) and 62 were nonsubdiaphragmatic (group 2). The completeness of the ablation was assessed with contrast-enhanced computer tomography (CT) 1 month. If residual tumor was documented, RFA was repeated. Complication occurrence, complete ablation, and local tumor progression and new lesions rates between these two groups were compared by the χ2 test or Fisher exact test.
Results The complete ablation rate in group 1 was 92.1% (70/76) and 98.4% (61/62) in group 2, with no significant statistical difference. The local tumor progression and new lesions rate were 19.7% (15/76) and 6.5% (4/ 62), respectively (χ 2 = 5.08, P = 0.02). The disease-free survival were (21.0±1.4) months and (24.7 ± 1.7) months, respectively (χ 2 = 3.84, P = 0.05). Complications were observed in 10 patients, and statistically significant differences existed between the groups in hydrothorax occurrence rate (χ2=4.52, P=0.034). Neither RFA-related deaths nor tumor seeding occurred. The technical success rate was 100%.
Conclusion RFA is a valid and safe, minimally invasive treatment method. The location of the tumor is a risk factor in impairing the ablation results. Finding recurrence around the ablation area in sub diaphragmatic tumors is much easier than in centric ones. Coordination in operation and a shorter follow-up interval for imaging are recommended.