Long-Term Survival after Radiofrequency Ablation of Lung Oligometastases from Five Types of Primary Lesions: A Retrospective Evaluation

Purpose To conduct a retrospective evaluation of long-term survival after radiofrequency (RF) ablation for lung oligometastases from 5 types of primary lesions. Materials and Methods The study population consisted of 123 patients with lung oligometastases from colorectal cancer (CRC), non–small-cell lung cancer, hepatocellular carcinoma, esophageal cancer, and renal-cell carcinoma treated with RF ablation. Lung oligometastases were defined as 1–5 metastases confined to the lung while the primary cancer and other metastases were eradicated. Overall survival (OS) and recurrence-free survival (RFS) were estimated for the overall study population and for patients with each type of primary lesion. The OS and RFS rates were compared with those of the patients with any of the other four primary lesion types. Finally, various variables were analyzed to determine what factors influenced OS and RFS. Results The median follow-up was 45.7 months, and the 5-year OS and RFS rates for all 123 patients were 62% and 25%, respectively. The OS time for patients with metastases from CRC was significantly longer (P = .042); it was significantly shorter (P = .022) in patients with metastases from esophageal cancer. Longer disease-free interval was significantly (P = .015) associated with better OS. There was no variable significantly associated with OS and RFS on multivariate analyses. Conclusions Data from this single-center study appear promising in terms of long-term survival after RF ablation of lung oligometastases from 5 primary lesions.