Liver-directed therapies in liver metastases from neuroendocrine tumors of the gastrointestinal tract

Presence of liver metastases in neuroendocrine tumors is a major factor altering both quality of life and prognosis. Surgery is recognized as the sole curative treatment. When it is not possible, radiological directed therapies are crucial, particularly in liver metastases from the small bowel. Thermal ablative therapies as radiofrequency ablation and microwave are alternative treatments alone or in combination with surgery. Hepatic artery embolization or chemoembolization, as radioembolization, has been shown to have good clinical, biochemical, and morphological responses when liver burden does not permit ablative therapies. However, technical issues are multiple and there is no randomized study to compare their efficacy. The choice of management depends on liver burden and metastases pattern, but also on origin of the primary tumor, tumor differentiation, and tumor proliferative activity. These patients should benefit of a multidisciplinary management to limit morbidity and mortality.