Neuroendocrine tumors of the duodenum and pancreas

The incidence of neuroendocrine tumors (NET) has increased worldwide by 3-5 times over the last decades. This is mainly based on the broad use of imaging modalities such as computed tomography (CT) and endoscopic approaches. As a consequence many duodenal and pancreatic tumors are detected in an early stage resulting in an improved prognosis of these patients. Besides the measurement of serum chromogranin A and 5-hydroxy indolic acid measured in 24 h urine collection, CT, endosonographic ultrasound (EUS) and endoscopy are important diagnostic tools. About 20% of all patients with pancreatic and duodenal NETs are diagnosed because of specific symptoms. More than 95% of diagnosed NETs are sporadic tumors. Whenever possible these patients should be treated by resection. Benign neuroendocrine duodenal tumors up to 1 cm in size can be removed endoscopically. The endoscopic resection of larger tumors should be performed surgically. The therapy of hereditary NETs of the duodenum and the pancreas should be decided after interdisciplinary discussion. However, even these patients seem to benefit from resection. In case of metastatic disease debulking surgery should be considered if more than 90% of the tumor mass can be resected. In patients with extensive liver metastases but resectable primary NET, liver transplantation is a reasonable option. There is no consensus about adjuvant or neoadjuvant treatment of duodenal or pancreatic NETs. The therapy with everolimus or sunitinib in advanced tumor stages has shown promising results. The administration of somatostatin analogues or antacids is appropriate for symptom reduction.