Percutaneous radio-frequency ablation of hepatic metastases from colorectal cancer: Long-term results in 117 patients

PURPOSE: To describe the results of an ongoing radio-frequency (RF) ablatio n study in patients with hepatic metastases from colorectal carcinoma. MATERIALS AND METHODS: In 117 patients, 179 metachronous colorectal carcino ma hepatic metastases (0.9-9.6 cm in diameter) were treated with RF ablatio n by using 17-gauge internally cooled electrodes. Computed, tomographic fol low-up was performed every 4-6 months. Recurrent tumors were retreated when feasible. Time to new metastases and death for each patient and time to lo cal recurrence for individual lesions were modeled with Kaplan-Meier analys is. Modeling determined the effect of number of metastases on the time to n ew metastases and death and effect of tumor size on local recurrence. RESULTS: Estimated median survival was 36 months (95% Cl; 28, 52 months). E stimated 1, 2, and 3-year survival rates were 93%, 69%, and 46%, respective ly. Survival was not significantly related to number of metastases treated. In 77 (66%) of 117 patients, new metastases were observed at follow-up. Es timated median time until new metastases was 12 months (95% Cl; 10, 18 mont hs). Percentages of patients with no new metastases after initial treatment at 1 and 2 years were 49% and 35%, respectively. Time to new metastases wa s not significantly related to number of metastases. Seventy (39%) of 179 l esions developed local recurrence after treatment. Of these, 54 were observ ed by 6 months and 67 by 1 year. No local recurrence was observed after 18 months. Frequency and time to local recurrence were related to lesion size (P less than or equal to .001). CONCLUSION: RF ablation is an effective method to treat hepatic metastases from colorectal carcinoma.