The European Neuroendocrine Tumor Society (ENETS) proposed standard of care guidelines for pathology in 2009. Since then, profound changes in the classification have been made, dividing neuroendocrine neoplasia (NEN) into well-differentiated neuroendocrine tumors (NET) and poorly differentiated neuroendocrine carcinomas (NEC) in the 2010 WHO classification. The 7th edition of the TNM classification (2009) included NEN for the first time, widely adapting ENETS proposals but with some differences for NEC and for NET of the pancreas and the appendix. Therapy guidelines for gastroenteropancreatic NET were updated in 2016. The need for an update of the standards of care prompted the ENETS to organize a consensus conference which was held in Antibes in 2015; a working group was designated to propose pathological standards of care.

Keywords:
Classification, Immunohistochemistry, Neuroendocrine tumor, Grading, Differentiation
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2017
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