Neuroendocrine tumors of the small intestine
Neuroendocrine tumors of the gastrointestinal tract constitute about 2% of all tumors in the gastrointestinal tract. Most are characterized by slow growth, often over years. These tumors can be found in the various organs of the digestive system: the small intestine, colon, stomach, appendix and rectum.
Like other neuroendocrine tumors, the small intestine neuroendocrine tumors are classified as functional and non-functional. The most common functional tumors of the small intestine are related to the secretion of serotonin and other substances that cause carcinoid syndrome manifested by flushing, diarrhea and shortness of breath. Excessive secretion of serotonin can also cause the formation of fibrosis (connective tissue) in various places and consequently damage their function. For example, damage to the mesentery tissue, which holds the small intestine, can lead to intestinal obstruction and heart valve damage. Therefore, in addition to treating the tumor, it is very important to reduce the secretion of serotonin from the tumor cells.