ENETS Consensus Guidelines for the Standards of Care in Neuroendocrine Tumors: Towards a Standardized Approach to the Diagnosis of Gastroenteropancreatic Neuroendocrine Tumors and Their Prognostic Stratification

BackgroundSeveral recent publications have focused on the application of the WHO classification of GEP-NETs and proved its effectiveness, supporting the concept that the various GEP-NET types also differ in their clinical behavior.Because of this biological diversity, the treatment of GEP-NETs is becoming more and more type-specific [4][5][6][7][8][9][10][11] .Recent data from the German NET registry have revealed that approximately one third of the cases reported between 2000 and 2006 lack a documented histopathological diagnosis, and in even more cases the tentative diagnosis of a NET was not confirmed by using neuroendocrine markers, nor was the proliferation determined by using Ki67/MIB1 [Plöckinger, unpubl.data].