Abstract
Background : To determine the efficacy and limitations of radiofrequency ablation (RFA) for colorectal liver metastases, the local control rate and risk factors of recurrence were compared for RFA and hepatic resection (HR). Methods : From April 2002 to June 2010, 28 patients underwent RFA and 42 patients underwent hepatic resection for colorectal liver metastases. The rate of local recurrence along the ablated or resected margin was evaluated in these patients. Results : Local recurrence was seen in 8 patients (19.0%) after HR and in 15 patients (53.6%) after RFA. The 3-year survival rate after HR (63.0%) was also better than that after RFA (42.2%). However, the 5-year survival rate did not significantly differ between patients with HR and those with RFA. Notably, the local recurrence rate after RFA was significantly higher than that after HR in patients with tumors sized 20 mm or more (p<0.001), while the local recurrence rate did not significantly differ between the 2 therapeutic modalities in patients with tumors smaller than 20 mm (p=0.722). Multivariate analysis of all the patients showed that the use of RFA as initial therapy (p<0.001), venous invasion of the primary tumor, v2-3 (p=0.004), and multiple liver metastases (p=0.016) were independent risk factors for local recurrence. Conclusions : RFA had a higher risk of local recurrence than HR, especially in patients with tumors larger than 20 mm. The indications for RFA should be considerably restricted, considering its limited efficacy.
