Surgical management of hepatic neuroendocrine tumor metastasis: Results from an international multi-institutional analysis

Background: Management of neuroendocrine tumor liver metastasis (NELM) remains controversial, with some advocating an aggressive surgical approach while others have adopted a more conservative strategy. We sought to define the efficacy of the surgical management of NELM in a large multicenter international cohort of patients. Methods: We identified 339 patients who underwent surgical management for NELM from 1985 to 2009 from an international database of eight major hepatobiliary centers. Relevant clinicopathologic data were assessed using Kaplan-Meier and Cox regression models. Results: Most patients had a pancreatic (40%) or small bowel (25%) neuroendocrine tumor (NET) primary. The majority of patients (60%) had bilateral liver disease. At surgery, 78% of patients underwent hepatic resection, 3% ablation alone, and 19% resection + ablation. Major hepatectomy was performed in 45% of patients, and 14% underwent a second liver operation. Carcinoid was the most common NET histological subtype (53%). Median survival was 125 months, with overall 5- and 10-year survival of 74%, and 51%, respectively. Disease recurred in 94% of patients at 5 years. Patients with hormonally functional NET who had R0/R1 resection benefited the most from surgery (P = 0.01). On multivariate analyses, synchronous disease [hazard ratio (HR) = 1.9], nonfunctional NET hormonal status (HR = 2.0), and extrahepatic disease (HR = 3.0) remained predictive of worse survival (all P < 0.05). Conclusions: Liver-directed surgery for NELM is associated with prolonged survival; however, the majority of patients will develop recurrent disease. Patients with hormonally functional hepatic metastasis without prior extrahepatic or synchronous disease derive the greatest survival benefit from surgical management.