What are neuroendocrine tumors?

As their name suggests, neuroendocrine tumors (NETs) arise from neuroendocrine cells, which can secrete hormones such as serotonin, insulin, and glucagon. These tumors can develop in various parts of the body. About one-third occur in the lungs and two-thirds in the digestive system : stomach, pancreas, intestines, colon…

Neuroendocrine tumors are quite rare, with an incidence of no more than 2–5 cases per 100,000 people per year, mainly affecting individuals aged 40–60¹. 

NETs are somewhat difficult to diagnose because they are highly heterogeneous: they can range widely in location and prognosis, from indolent tumors that show little growth over a decade to very serious, fast-progressing tumors. Multidisciplinary management in an expert center such as Institut Curie, with its specialists including pulmonologists, gastroenterologists, and endocrinologists, is strongly recommended.
 

Risk factors for neuroendocrine tumors 

The vast majority of NETs have no known risk factors. Fewer than 5%² are genetic. They occur in patients with hereditary syndromes such as multiple endocrine neoplasia type 1 (MEN1), which can lead to duodenal, pancreatic, thymic, or bronchial NETs, or von Hippel–Lindau Disease or neurofibromatosis type 1, both of which may cause pancreatic or other NETs. 

Note that smoking may play a role in poorly differentiated neuroendocrine carcinomas.

[1] Source: Réseau GTE (the Endocrine Tumor Study Group network)

[2] Source:  GTE network