Introduction to a revised clinicopathological classification of neuroendocrine tumors of the gastroenteropancreatic tract

A revised clinicopathological classification of neuroendocrine tumors of th e gastroenteropancreatic tract has been recently developed under the auspic es of the World Health Organization (WHO) according to advances in the fiel d of tumor biology. Here the classification is briefly outlined and discuss ed together with the guidelines for a correct approach to the histopatholog ical diagnosis of neuroendocrine tumors and the interpretation of the class ification schemes covering clinical (hyperfunctional syndromes included), p athological and biological patterns, with special emphasis on tumor prognos is.