Liver metastases occur in 46-93% of patients with neuroendocrine neoplasms (NENs). Presence and extension of liver metastases are considered important prognostic factors, as they may significantly impair the patient’s quality of life, because of either tumor bulk or hormonal hypersecretion. Therapies for NEN liver metastases include surgical resection, liver transplantation, chemotherapy and biotherapy. Surgery is the gold standard for curative therapy, but in most of NEN patients with liver metastases, when surgery can not be applied, minimally invasive therapeutic approaches are adopted. They include trans-arterial embolization (TAE), trans-arterial chemoembolization (TACE), radiofrequency thermal ablation and new emerging techniques. TAE is based on selective infusion of particles in the branch of the hepatic artery supplying the tumor lesions. The goal of TAE is to occlude tumor blood vessels resulting in ischemia and necrosis. Many reports have shown that TAE can reduce tumor size and hormone output, resulting in palliation of symptoms without the use of cytotoxic drugs, resulting in better tolerability. This review will focus on TAE performance and safety in NEN patients with liver metastases.

Purpose: Pancreatic neuroendocrine tumors (pNETs) are frequent in multiple endocrine neoplasia type 1 (MEN1) syndrome. They are usually not surgically treated unless larger than 1 to 2 cm or a growth rate > 0.5 cm per year. Somatostatin analogues represent one of the main therapeutic options in pNETs, but they have never been prospectively investigated in MEN1-related pNETs. The aim of this study was to prospectively evaluate the effectiveness of lanreotide in patients with MEN1-related pNETs < 2 cm. Methods: MEN1 patients with 1 or more pNETs < 2 cm of maximal diameter were considered. Study design was prospective observational, comparing patients treated with lanreotide autogel 120 mg every 28 days (LAN group) and patients in active surveillance, not receiving any therapy (AS group). Results: Forty-two patients were enrolled: 23 in LAN and 19 in AS group. Median follow-up was 73 months. Initial imaging identified a total of 91 pNETs. The median progression-free survival was significantly longer in the LAN than in the AS group (median not reached vs 40 months, P < 0.001). In the LAN group, 4 patients had an objective tumor response, 15 patients had stable disease, while 4 had tumor progression. In the AS group, 13 patients had pNET progression, while 6 were stable. Conclusions: This is the first prospective study evaluating the efficacy of somatostatin analogues in MEN1-related pNETs. These findings highlight that lanreotide autogel is effective as antiproliferative therapy in MEN1-related pNETs < 2cm, suggesting the utility of somatostatin analogues to arrest the development of tumor lesions as well as to delay or avoid pancreatic surgery.