Trans-Arterial Embolization for Liver Metastases of Gastroenteropancreatic Neuroendocrine Tumors: Response Indicates Survival Benefit?

Abstract

Objective: To determine the impact of trans-arterial embolization (TAE) on overall survival (OS) in patients with liver metastases from gastroenteropancreatic neuroendocrine tumors (LM-GEP-NETs) and to identify factors that may influence tumor response to TAE treatment.

Methods: This study included patients with histologically and radiologically confirmed LM-GEP-NETs who received TAE treatment at The First Affiliated Hospital, Sun Yat-sen University, between November 2016 and January 2023. Imaging responses were assessed using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and modified RECIST (mRECIST) criteria. Tumor response was defined as complete or partial remission.

Results: In total, 267 patients with LM-GEP-NETs were included. Patients with liver tumor burdens <25%, 25-50%, and ≥50% had progressively worse OS (p < 0.005). According to the RECIST criteria, 65.9% of patients exhibited tumor responses. Using the mRECIST criteria, 77.5% of patients showed tumor responses. Survival analyses with log-rank tests indicated that patients with tumor responses assessed using either the RECIST or mRECIST criteria had significantly better OS (p = 0.015 and p = 0.023, respectively). Further logistic regression analyses showed that early TAE (within 4 months after diagnosis of liver metastases) was associated with tumor responses assessed using RECIST or mRECIST. These results were further verified using propensity score matching and inverse probability treatment weighting adjusted datasets.

Conclusions: A higher liver tumor burden was associated with poorer OS in patients with LM-GEP-NETs. Tumor response after TAE indicates survival benefits. Early TAE (within 4 months of diagnosis) was associated with better treatment responses.