Outcomes of Laparoscopic Tumor Ablation for Neuroendocrine Liver Metastases: a 20-year Experience

Background: Since neuroendocrine tumors have an indolent behavior, studies looking at oncologic outcomes should report a long-term follow-up. Over the years, we have been treating selected patients with neuroendocrine liver metastases (NELM) with laparoscopic ablation (LA) and reported favorable local tumor control. The aim of this study is to see whether this local efficacy translates into long-term oncologic outcomes.

Methods: This was an IRB-approved study of patients who underwent LA for NELM at a single center. Overall and progression-free survivals were analyzed using Kaplan-Meier and Cox proportional hazards model.

Results: Study included 58 women and 71 men with a median age of 58 (IQR 47-67) years. Tumor type included carcinoid (n = 92), pancreatic islet cell (n = 28), and medullary thyroid cancer (n = 9). There was a median of 6 (IQR 3-8) tumors, measuring 1.6 (IQR 1.1-2.4) cm. At a median follow-up of 73 (IQR 34-135) months, local liver recurrence per patient, new liver recurrence, and new extrahepatic recurrence rates were 22, 68, and 33%, respectively. Local tumor recurrence per lesion was 5% (n = 42/770). Median overall survival was 125 months, with 5-year, and 10-year overall survivals being, 76%, and 59%, respectively; and median disease-free survival was 13 months, with 5-year, and 10-year progression-free survivals being 26%, and 6%, respectively. On Cox proportional hazards model, overall survival was independently predicted by tumor size, grade, and resection status of primary.

Conclusion: To our knowledge, this is the largest single-center experience with the longest follow-up regarding the utilization of LA for NELM. Our results demonstrate that in selected patients, LA achieves a 95% local tumor control and 59% 10-year overall survival.