Changes in Outcomes of Hepatic Cytoreduction for Neuroendocrine Liver Metastases over Two Decades: From Major Hepatectomy to Parenchyma-Sparing Approaches.

BACKGROUND: Surgical and systemic management of neuroendocrine liver metastases (NELM) has evolved over the past decades. This study aimed to evaluate temporal changes in prognosis and identify factors associated with improved survival after hepatic cytoreduction for NELM. PATIENTS AND METHODS: Patients who underwent hepatic cytoreduction for NELM during 1998-2023 were retrospectively analyzed and divided into earlier period (EP, 1998-2008) and later period (LP, 2009-2023) cohorts. Clinicopathological features, perioperative outcomes, and survival were compared. Covariate-adjusted survival curves and propensity score matching were used to compare overall survival (OS) between major hepatectomy and liver-parenchyma-sparing cytoreduction (LPSC). RESULTS: The study included 293 patients, 132 in the EP cohort and 161 in the LP cohort. The LP cohort had a lower rate of major hepatectomy (32.9% versus 60.0%, P < 0.001) and significantly better OS (10-year OS rate, 67.4% versus 44.2%, P < 0.001). Major hepatectomy remained independently associated with worse OS after adjustment for treatment period and other covariates [hazard ratio (HR) 1.74, 95% confidence interval (CI) 1.02-2.98, P = 0.043]. This association was consistent after propensity score matching. LP patients received local therapy (including surgery, percutaneous ablation, and transarterial embolization), somatostatin analogs, and targeted agents more frequently than EP patients after tumor progression. CONCLUSIONS: OS after hepatic cytoreduction for NELM improved during 1998-2023 in parallel with a shift from extensive resections to a parenchyma-sparing approach and the integration of modern systemic therapies. These findings support individualized cytoreductive strategies that balance tumor reduction with preservation of liver parenchyma and future treatment options.