Radiofrequency ablation of concomitant and recurrent pulmonary metastases after surgery for colorectal liver metastases.

BACKGROUND: To evaluate our experience of radiofrequency ablation (RFA) of pulmonary metastases in patients with resected colorectal liver metastases who had concomitant or recurrent pulmonary metastases.

METHODS: Clinical and treatment variables of patients undergoing RFA were collected, and their association with survival was examined. Survival analysis was performed by the Kaplan-Meier method.

RESULTS: RFA was performed as concomitant sequential treatment of extrahepatic pulmonary metastases after hepatectomy in 19 patients (30%) and as salvage treatment for pulmonary recurrences after hepatectomy in 45 patients (70%). Patients undergoing sequential treatment had a median survival of 31 (95% confidence interval [CI] 21.8-40.6) months compared to 59 (95% CI 35.0-82.0) months in the salvage treatment group (P = 0.142). The disease-free survival (DFS) was 9 (95% CI 1.0-18.8) months in the sequential treatment group and 16 (95% CI 8.1-23.1) months in the salvage treatment group (P = 0.023). Liver metastases occurring within 12 months of the primary tumor negatively influenced overall survival (OS) and DFS in the sequential treatment group (P = 0.003 and P = 0.091). Poorly differentiated tumor (P = 0.001) was associated with a poorer OS, and prehepatectomy carcinoembryonic antigen > 200 ng/ml (P = 0.017) and bilateral pulmonary metastases (P = 0.030) were associated with a shorter DFS in the salvage treatment group.

CONCLUSIONS: The DFS and OS of patients undergoing sequential RFA of extrahepatic pulmonary metastases after hepatectomy appeared shorter when compared to patients who underwent RFA as salvage treatment for pulmonary recurrences after hepatectomy. It nonetheless remains better than the historical results of chemotherapy alone and thus supports the use of RFA as an ablative technology to achieve tumor control.