Timing of disease occurrence and hepatic resection on long-term outcome of patients with neuroendocrine liver metastasis

Background and Objectives: The objective of the study was to evaluate the impact of timing of disease occurrence and hepatic resection on long-term outcome of neuroendocrine liver metastasis (NELM). Methods: A total of 420 patients undergoing curative-intent resection for NELM were identified from a multi-institutional database. Date of primary resection, NELM detection and resection, intraoperative details, disease-specific (DSS), and recurrence-free survival (RFS) were obtained. Results: A total of 243 (57.9%) patients had synchronous NELM, while 177 (42.1%) developed metachronous NELM. On propensity score matching (PSM), patients with synchronous versus metachronous NELM had comparable DSS (10-year DSS, 76.2% vs 85.9%, P = 0.105), yet a worse RFS (10-year RFS, 34.1% vs 59.8%, P = 0.008). DSS and RFS were comparable regardless of operative approach (simultaneous vs staged, both P > 0.1). Among patients who developed metachronous NELM, no difference in long-term outcomes were identified between early (≤2 years, n = 102, 57.6%) and late (>2 years, n = 68, 42.4%) disease on PSM (both P > 0.1). Conclusions: Patients with synchronous NELM had a higher risk of tumor recurrence after hepatic resection versus patients with metachronous disease. The time to development of metachronous NELM did not affect long-term outcome. Curative-intent hepatic resection should be considered for patients who develop NELM regardless of the timing of disease presentation.