[Multiple endocrine neoplasia (MEN)]

[Endocrine tumors: clinical overview]

The term endocrine tumor incorporates all neoplasms which originate from the various endocrine organs. Endocrine tumors can be characterized by different criteria: localization, endocrine function, dignity (i.e. tumorigenesis, sporadic or hereditary). These characteristics also determine the clinical outcome. The clinical history, symptoms and physical examination findings (e.g. amenorrhea, skin alterations, striae, virilization, increased blood pressure and flush) direct the diagnostic process of functioning endocrine tumors. Laboratory findings (endocrine parameters) are needed to establish a diagnosis supplemented by imaging for localization and special investigations (ophthalmological examination). In hereditary tumor syndromes, the familial history and molecular genetic testing and screening of family members are essential for establishing the diagnosis and achieve optimal and early treatment. Ideally, affected family members can be treated before clinical symptoms or metastatic disease occurs, improving outcome and prognosis. Incidentalomas are increasingly found due to widespread use of imaging techniques, especially in the thyroid, adrenal glands, pancreas and pituitary gland. In incidentalomas the functional status and risk of malignancy has to be evaluated as both parameters determine therapy decisions. The aim of this introductory article is to give an overview about particular features of endocrine tumors, clinical and related aspects for the diagnostic and therapeutic approach. The clinical features of tumors of the pituitary, parathyroid and adrenal glands and the gastroenteropancreatic system are summarized according to localization.