[Difficulties and challenges in pathological diagnosis of gastrointestinal pancreatic neuroendocrine tumors]

In the 5th edition of WHO Classification of Digestive System Tumours, the classification and designation of gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN) were updated, and G3 was redefined. Therefore, the differential diagnosis between well-differentiated neuroendocrine tumour G3(NETG3) and poorly differentiated neuroendocrine carcinomas (NEC) is both important and difficult, which has important clinical treatment and prognostic significance. Based on the latest WHO and 2020 Chinese consensus on pathological diagnosis of GEP-NEN, this paper proposed a comprehensive analysis on the differential diagnosis of gastrointestinal pancreatic neuroendocrine tumor from four aspects, including tumor morphological differentiation、tumor proliferative activity, gene change and disease progression. However, even with the above four diagnostic tools, there are still some difficulties and challenges in the work of pathological diagnosis. This paper briefly expounds and discusses them together, in order to improve the clinical application value.