Controversies and prospects for surgical treatment of pancreatic neuroendocrine neoplasms with liver metastases

Abstract

The incidence of pancreatic neuroendocrine neoplasm(pNEN) increased over the past two decades. Liver metastasis, the most common type of distal metastasis, is also one of the most important prognostic factors. Although several medical treatments, including biotherapy, chemotherapy, targeted therapy, peptide receptor radionuclide therapy and locoregional therapy, are available for pNEN with liver metastases, surgery is still the only possible treatment for cure. Currently, there are several controversies as regards surgical treatment for pNEN with liver metastases. These controversies include, but are not limited to, whether surgical resection is appropriate for pancreatic neuroendocrine tumor G3 with liver metastases, how to classify primary lesion and hepatic metastases comprehensively and accurately, what is the optimal surgical strategy for type Ⅱ liver metastases, who can benefit greatly from cytoreduction, and how to refine the Milan criteria for liver transplantation. This article aims to discuss those main controversies and provide prospects for future clinical trials.