Neuroendokrine Tumoren des Dünndarms nehmen zu: frühe Tumoren und deren Management

Abstract

Neuroendocrine tumors (NETs) of the small bowels are on the rise: in the US they have increased by 300-500% in the last 35 years. At the same time their prognosis has been much improved. Most NETs of the duodenum are nowadays detected "incidentally" and therefore recognized at an early stage. Duodenal NETs that are well differentiated, not larger than 10 mm in greatest dimension and limited to the mucosa/submucosa can be endoscopically resected. In NETs with a size between 10 mm and 20 mm the therapeutic strategy has to be individually discussed. Endoscopic ultrasound is the method of choice to determine tumor size and depth of infiltration. Surgery is indicated for well differentiated duodenal NETs greater than 20 mm, for localized sporadic gastrinomas and for localized poorly differentiated NE cancers. Surgery is also indicated for localized/regional ileal NETs. Advanced ileal NETs with a carcinoid syndrome are treated with stable somatostatin analogs. This treatment also significantly improves the (progression-free) survival in patients with metastatic NETs of the ileum. For optimal NET management tumor biology, type, localization and stage of the neoplasm as well as the individual situation of the patient have to be taken into account.

Neuroendocrine tumors of the small bowels are on the rise: Early aspects and management

“…Controlled studies on the different approaches are lakking [12] . On the other hand, there is wide consensus that in operable patients, non-functional, duodenal NETs > 20 mm as well as all sporadic gastrinomas are to be subjected to surgical therapy [13,77] .…”

“…In none of the cases of somatostatin-cell tumors reported so far did the patients develop 'somatostatinoma' syndrome (diabetes mellitus, diarrhea, steatorrhoea, hypoor achlorhydria, anemia and gallstones) that has been described in association with some pancreatic somatostatincell tumors [46] . Gangliocytic paragangliomas are characterized by their triphasic cellular differentiation consisting of neuroen- [77]); D: Sporadic gastrinoma of the duodenal bulb; E: Sporadic gastrinoma of the second part of the duodenum; F: Multiple duodenal gastrinomas in a patient with multiple endocrine neoplasia type 1 disease; G: 12 mm-sized NET of the distal ileum. Both tumor localisation and histological diagnosis were established using double balloon enteroscopy [34] .…”

“…The primary tumor was located 8 cm proximal to the ileocecal valve. Ileocolonoscopy allowed not only tumor localization, but also histological verification of ileal NET disease (modified from reference [77]). docrine cells (producing somatostatin and/or pancreatic polypeptide), spindle-shaped Schwann-like cells and ganglion cells.…”

Synchronous Duodenal Carcinoid and Adenocarcinoma of the Colon

“…Surgical management is the treatment of choice for duodenal carcinoids that are nonfunctional but more than 20 mm in size. Tumors extending beyond the submucosa (T2-T4) or that have metastasized to lymph nodes should be managed surgically [ 7 - 9 ].…”