Neuroendocrine Tumor of the Gastrointestinal Tract: Risk Factors

Approved by the Cancer.Net Editorial Board, 08/2018

ON THIS PAGE: You will find out more about the factors that increase the chance of developing a GI tract NET. Use the menu to see other pages.

A risk factor is anything that increases a person’s chance of developing a tumor. Although risk factors often influence the development of a tumor, most do not directly cause cancer. Some people with several risk factors never develop a tumor, while others with no known risk factors do. Knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices.

What causes GI tract NETs is unknown, and no avoidable risk factors have been found. However, the following factors may raise a person’s risk for this type of tumor:

  • Family history and inherited syndromes. Multiple endocrine neoplasia type 1 (MEN1) is a hereditary condition that increases the risk of developing tumors in the pituitary gland, parathyroid gland, and pancreas. It is estimated that around 10% of GI tract NETs are associated with MEN1. In addition, some families have multiple relatives with GI tract NETs but no clear association with MEN1. This suggests that there may be other genetic risk factors not yet discovered.

    Other hereditary conditions related to NETs include Von Hippel-Lindau syndrome, neurofibromatosis type 1, multiple endocrine neoplasia type 2 (MEN2), and tuberous sclerosis complex.

  • Race and gender. NETs are more common among white people than black people. They are slightly more common in women than in men.

  • Age. For GI tract NETs, the average age at diagnosis is 55 to 65. Children rarely develop NETs.

  • Other medical conditions. People with diseases that damage the stomach and reduce acid production have a greater risk of developing a NET of the stomach. In particular, people with pernicious anemia have a higher risk of developing a NET of the stomach. Pernicious anemia is a type of anemia in which a person has very large, malformed red blood cells.

  • Environment and diet. There are no known connections between the environment and what a person eats and the risk of developing a GI tract NET.

The next section in this guide is Symptoms and Signs. It explains what body changes or medical problems a GI tract NET can cause. Use the menu to choose a different section to read in this guide.