Neuroendocrine Tumors Health Article

Definition

Neuroendocrine tumors are tumors that develop from the cells of the diffuse neuroendocrine system, such as the enterochromaffin (EC) cells. These tumors are characterized by the presence of cells that possess secretory granules and have the ability to secrete neurohormones.

Description

The endocrine system is a network of glands consisting of endocrine cells that produce hormones in the body. The neuroendocrine system cells are specialized endocrine cells of the nervous system and produce neurohormones. Neuroendocrine cells do not form a specific gland; instead, they are found distributed in a wide variety of body organs where they help regulate body function.

Neuroendocrine tumors therefore represent a large class of cancers that can occur wherever neuroendocrine cells are found throughout the body. They are sometimes called carcinoid tumors, but it would be more accurate to consider these tumors as a sub-category of the larger family of neuroendocrine tumors. Neuroendocrine tumors are most often found in the digestive system and the lung. Statistically, 38% occur in the appendix, 23% in the ileum, 13% in the rectum and 11.5% in the bronchi. Neuroendocrine pancreatic tumors are rather rare cancers with an incidence of 1-2 cases per 100, 000 people. They occur with the same frequency in men and women and the average age at diagnosis is 53 years. Neuroendocrine tumors are also known as apudomas, or tumors that contain apud cells. These cells release excessive amounts of a variety of neurohormones in the bloodstream with chemical composition that varies with location, as does their effect on the body. Neuroendocrine tumors therefore have symptoms that vary with location. Unlike other cancers that are located in a specific organ, the hormone-releasing action of these tumors causes other symptoms to appear in many other organs of the body as well. The majority of neuroendocrine tumors can give rise to metastases with time if they are left untreated.