Currently available treatment options for neuroendocrine liver metastases

Abstract

Neuroendocrine neoplasms (NEN) are frequently characterized by a high propensity for metastasis to the liver, which appears to be a dominant site of distant-stage disease, affecting quality of life and overall survival. Liver surgery with the intention to cure is the treatment of choice for resectable neuroendocrine liver metastases (NELM), aiming to potentially prolong survival and ameliorate hormonal symptoms refractory to medical control. Surgical resection is indicated for patients with NELM from well-differentiated NEN, while its feasibility and complexity are largely dictated by the degree of liver involvement. As a result of advances in surgical techniques over the past decades, complex 1- and 2-stage, or repeat liver resections are performed safely and effectively by experienced surgeons. Furthermore, liver transplantation for the treatment of NELM should be anchored in a multimodal and multidisciplinary therapeutic strategy and restricted only to highly selected individual cases. A broad spectrum of interventional radiology treatments for NELM have recently been available, with expanding indications that are more applicable, as they are less limited by patient- and tumor-related parameters, being therefore important adjuncts or alternatives to surgery. Overall, liver-targeted treatment modalities may precede the administration of systemic molecular targeted agents and chemotherapy for patients with liver-dominant metastatic disease; these appear to be a crucial component of multimodal management of patients with NEN. In the present review, we discuss surgical and non-surgical liver-targeted treatment approaches for NELM, each complementing the other, with a view to assisting physicians in optimizing multimodal NEN patient care.

Keywords: Neuroendocrine; ablation; embolization; liver metastasis; surgery.

Figure 1

Proposed types of neuroendocrine liver metastases distribution [13]

Figure 2

Treatment algorithm for well-differentiated (G1/G2) neuroendocrine liver metastases TACE, transarterial chemoembolization; TAE, transarterial embolization; RE, radio-embolization; PPRT, peptide receptor radionuclide therapy, OLT, orthotopic liver transplantation; SA, somatostatin analogues; panNEN, pancreatic neuroendocrine neoplasm; IFNa, interferon alpha; SI-NEN, small intestine neuroendocrine neoplasm; PVE, portal vein embolization; PVL, portal vein ligation; ALPPS, associating liver partition and portal vein ligation for staged hepatectomy