Neuroendocrine tumors (NETs) include a heterogeneous group of neoplasms that can arise from various neuroendocrine cells in many organs and tissues in the body. These tumors are characterized by their ability to produce peptides that lead to different endocrine syndromes. Many patients have nonspecific symptoms and can easily be confused. It is not unusual for patients to suffer for a long time before NETs are diagnosed, and almost 50% of all patients with NETs have regional or distant metastases at time of diagnosis. NETs are mainly sporadic, but also may occur as part of a complex familial endocrine cancer syndrome, like MEN1, MEN2, Von Hippel-Lindau disease, neurofibromatosis type 1 and multiple tuberous sclerosis.
NETs are rare, but their
NETs are rare, but their