Treatment of pulmonary colorectal metastases by radiofrequency ablation.

Petre, Elena N; Jia, Xiaoyu; Thornton, Raymond H; Sofocleous, Constantinos T; Alago, William; Kemeny, Nancy E; Solomon, Stephen B

UNLABELLED We evaluated the local tumor control and the survival benefit achieved with radiofrequency ablation (RFA) for nonoperable lung metastases in 45 patients with colorectal cancer. Median survival from the time of RFA was 46 months. One-, 2- and 3-year local tumor progression (LTP)-free survival rates were 92%, 77%, and 77%, respectively. RFA offers very good local control in patients with pulmonary metastases from colorectal cancer. BACKGROUND Radiofrequency ablation has emerged as a potential, lung function-preserving treatment of colorectal lung metastases. PATIENTS AND METHODS Forty-five patients with colorectal pulmonary metastases underwent computed tomography-guided RFA from December 2004 to June 2010. A baseline posttreatment scan was obtained 4-6 weeks after RFA and follow-up imaging studies every 3 months thereafter were obtained and compared to evaluate the tumor progression at site of ablation or elsewhere. The primary end points were LTP-free survival and overall survival from RFA procedure. The Kaplan-Meier method was used to analyze the end points. A Cox proportional hazard model with robust inference was used to estimate the associations between baseline factors and survival end points. RESULTS Sixty-nine metastases were ablated in 45 patients. Tumor size ranged from 0.4 to 3.5 cm. The median number of metastases ablated per patient was 1 (range, 1-3). Median follow-up after RFA was 18 months. Median survival from the time of RFA was 46 months (95% confidence interval [CI], 27.8-47.3). One-, 2- and 3-year overall survival rates from the time of RFA were 95% (95% CI, 82%-99%), 72% (95% CI, 52%-85%), and 50% (95% CI, 26%-71%), respectively. Nine of 69 lesions (13%) progressed and 4 were retreated with no progression after second RFA. Median time to progression was not reached. LTP-free survival from RFA was 92% (95% CI, 82%-97%) at 1 year, 77% (95% CI, 58%-88%) at 2 years, and 77% (95% CI, 58%-88%) at 3 years. CONCLUSION Radiofrequency ablation of lung metastases is an effective minimally invasive, parenchymal-sparing technique that has very good local control rates in patients with pulmonary metastases from colorectal cancer, with LTP-free survival of 77% at 3 years.