ABSTRACT
In this chapter we concentrate on the following neuroendocrine tumors: carcinoid tumors and pancreatic endocrine tumors.
Carcinoid tumors, related to the gastrointestinal tract, can be found in the stomach, jejunum, ileum, appendix, ascending colon, and colorectal. Carcinoid primary tumors occur in the appendix (38%), ileum (23%) and rectum (13%). Flushing is the most frequent symptom (94%), followed by diarrhea (78%) and abdominal pain or cramping (51%). Other symptoms include endocardial fibrosis, wheezing, myopathy, arthritis, arthralgias, and changes in mental state. Carcinoid syndrome occurs in fewer than 10% of patients with carcinoid tumors and has an incidence of about 3.2-5 cases per million of the population per year and results from excessive secretion of hormone products into the systemic circulation (e.g. adrenocorticotropic hormone (ACTH), gastrin, pancreatic polypeptide, insulin, tachykinins, vasoactive intestinal polypeptide (VIP), serotonin, or 5-hydroxyindoleacetic acid (5-HIAA)).
