Laparoscopic radiofrequency thermal ablation of neuroendocrine hepatic metastases: Long-term follow-up

Background: Since our first report 13 years ago, laparoscopic radiofrequency ablation has been incorporated into the treatment algorithm of patients with neuroendocrine liver metastases. The aim of this study is to report long-term oncologic results. Methods: Eighty-nine patients with neuroendocrine hepatic metastases underwent 119 laparoscopic radiofrequency ablation sessions within 13 years. Data were obtained from a prospective, Institutional Review Board approved database. Univariate Kaplan Meier and multivariate Cox proportional hazards model were used for statistical analyses. Data are expressed as mean ± standard error of the mean. Results: Thirty-five women and 54 men with a mean age of 56 ± 1.4 years were included in this study. Tumor types included were carcinoid (n = 55), pancreatic islet cell (n = 23), and medullary thyroid cancer (n = 11). Mean tumor size was 3.6 ± 0.2 and the number of lesions was 6 ± 1. Perioperative morbidity was 6%, and 30-day mortality was 1%. Symptom relief was achieved in 97% of patients after radiofrequency ablation. Median follow-up was 30 ± 3 months. Twenty-two percent of patients developed local liver recurrence, 63% developed new liver lesions, and 59% developed extrahepatic disease in follow-up. Repeat radiofrequency ablation (27%) and chemoembolization (7%) were used to achieve additional local tumor control in follow up. Median disease-free survival was 1.3 years and the overall survival was 6 years after radiofrequency ablation. Liver tumor volume, symptoms, and extrahepatic disease were independent predictors of survival. Conclusion: To our knowledge, this is the largest prospective experience with radiofrequency ablation of neuroendocrine liver metastases. Effective symptom palliation and long-term local tumor control are possible in these patients with minimal morbidity.