Locoregional Therapies of NEN

Interventional Oncology (IO) is nowadays one of the four pillars of the modern Oncology, together with Clinical Oncology, Surgical Oncology, and Radiation Therapy, thanks to the several minimally invasive therapies provided and available both for radical and palliative purposes. Within the field of Neuroendocrine Tumors, IO plays an important role in the management of patients with liver metastases, where intra-arterial therapies, such as embolization, chemoembolization, and radioembolization, as well as percutaneous interventions, such as radiofrequency ablation and microwave ablation, are the more common options included into the treatment strategies. Intra-arterial options, originally introduced for treating HCC in clinical practice, gained attention in liver metastatic NET because of the outstanding results in symptoms control and for prolonging survival, with no or few side effects. On the other hand, liver ablation, firstly introduced for percutaneous imaging-guided approach and more recently also applied in open and laparoscopic setting, can provide eradication of liver metastases with less invasiveness than traditional surgery. Moreover, due to the high rate of relapse after radical treatments, new liver metastases can be further eradicated with percutaneous ablation, with no cumulative toxicity such as with repeated resections. For those reasons, a modern management of patients affected by Neuroendocrine Tumors cannot avoid to include the Interventional Oncology options within the discussion of dedicated Multidisciplinary Tumor Board.