Introduction: Percutaneous RFA is a minimally invasive technique that is gaining popularity in the management of colorectal liver metastases. The purpose of this study was to examine rates and patterns of recurrence following percutaneous RFA and open wedge resection for solitary liver metastasis. Methods: Retrospective review of a prospectively maintained database identified 30 patients between 1992 and 2002 who underwent non-anatomic wedge resection for a solitary liver metastasis. Since 1998, 21 patients were identified who underwent percutaneous RFA rather than resection. Serial imaging studies were retrospectively reviewed for evidence of recurrence. Results: Indications for RFA were prior liver resection (52%), medical comorbidity (38%), and unresectability (10%). Patients in the RFA group were more likely to have undergone prior liver resection, to have a disease-free interval (DFI) greater than one year, and to be female (Table). RFA was associated with a lower incidence of major complications (4 vs. 14%, P<0.01) and shorter hospital stays (1.3 vs. 8.1 days, P<0.01). After a median follow-up 62 and 13 months, respectively, true local liver disease-free survival (DFS) at the ablation/resection site at one year was 100% in the Wedge group and 52% in the RFA group (P<0.01), and overall liver DFS rates at one year were 86% and 49% (P<0.01). Long-term true local DFS was 85% in the Wedge group. Two patients in the RFA group were re-ablated and two patients were resected to improve “assisted” local DFS at one year to 74%. Median overall survival was 80 months in the Wedge group and 31 months in the RFA group. One-third of patients in each group presented with distant metastasis as a component of their first recurrence. Conclusions: Local and overall liver recurrences are common after percutaneous RFA but are potentially salvageable with close followup and reablation or resection for recurrence.

SD = standard deviation; NS = not significant