Endocrine Abstracts

According to the current WHO classification neuroendocrine neoplasias (NEN) are classified according to differentiation into well differentiated neuroendocrine tumors (NET) and poorly differentiated neuroendocrine carcinomas (NEC). NEN are classified in addition to organ of origin and grade. More recent molecular data confirms this approach as the identified mutation spectrum differs according to differentiation and organ of origin. However, NEN might be more heterogeneous: Expression data of a large series of pancreatic NET indicates that biologically meaningful subgroups can be defined as in other malignant neoplasms, the clinical role regarding prognosis and prediction to therapy response of such a classification will need to be examined.

More recently, a subset of highly proliferative G3 NEN were described to differ morphologically and biologically from NEC G3 and are best designated as well differentiated NET G3. Morphology is able to identify a subset of these tumors and further studies will show if molecular classifications will be able to help.