[Diagnostics and treatment in functional pancreatic neuroendocrine tumours]

Pancreatic neuroendocrine tumours (PNET) are rare entities with an annual incidence of < 100,000. About 1 - 2 % of pancreatic neoplasias are neuroendocrine tumours. About one third of these tumours secrete biologically active substances that lead to development of specific clinical syndromes. PNET may occur sporadically or in association with hereditary syndromes, such as multiple endocrine neoplasia type 1 (MEN1). Among the functional PNET, insulinomas and gastrinomas are the most common entities. In contrast, vasoactive intetinale peptide (VIP)-secreting tumours, glucagonomas, serotonin-secreting carcinoid tumors, and tumours with secretion of ectopic hormones, such as calcitonin, are extremely rare. Once diagnosis has been established on the basis of clinical and laboratory findings, localization of the source of pathologic hormone secretion is warranted. Imaging methods frequently used for localization of PNET comprise anatomical imaging modalities, computed tomography, and magnetic resonance imaging, endoscopic ultrasound, selective arterial catheterization with hepatic venous sampling, DTPA-octreotid scintigraphy and DOTA-D-Phe(1)-Tyr(3)-octreotid positron emission tomography. Therapy is based on the specific tumour entity and the extent of the disease. In the majority of patients, even in the case of malignant disease, a surgical approach is warranted, eventually combined with a medical treatment.