Gastrointestinal neuroendocrine tumors are rare cancerous tumors in neuroendocrine cells in your gastrointestinal (GI) tract. The most common treatment is surgery to remove the tumor.
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Gastrointestinal neuroendocrine tumors (GI NET) are rare cancerous tumors in neuroendocrine cells in your gastrointestinal (GI) tract. The most common treatment is surgery to remove tumors.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
A gastrointestinal neuroendocrine tumor is one of a group of uncommon tumors (neuroendocrine tumors) that start in specialized cells in your neuroendocrine system. Neuroendocrine cells link your endocrine system (which manages your hormones) and your nervous system. Neuroendocrine cells are scattered throughout your body, including your gastrointestinal tract.
Your gastrointestinal tract is part of your digestive system. Your GI tract is a tube-like pathway your body uses to digest food and liquid and to process waste. GI NETs (once called carcinoid tumors) typically develop in your small intestine and rectum, but may also appear in your stomach, appendix and esophagus. Gastrointestinal endocrine tumors can spread beyond your GI tract to your liver.
GI NET affects about 4 in 100,000 people. Each year, about 8,000 adults in the U.S. are diagnosed with gastrointestinal endocrine tumors. The condition typically affects people aged 55 to 65, but it can affect adults of any age. GI NET is more common in white people than in Black people. Women and people assigned female at birth are slightly more likely to develop GI NET than men and people assigned male at birth.
People may have these tumors without having symptoms. Some people are diagnosed with GI NET because they had an imaging test to diagnose an unrelated condition. When people do have symptoms, the symptoms are similar to symptoms for less serious illnesses. Common GI NET symptoms include:
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Medical researchers haven’t identified a specific cause. They’ve found links between GI NETs and hypochlorhydria (low stomach acid). People with certain inherited conditions and syndromes may develop GI NET. Those conditions and syndromes include:
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Yes, healthcare providers use a grading system to categorize the tumor so they can plan treatment. To establish a tumor grade, they examine cancerous cells under a microscope. That view shows them how many cells are dividing and how quickly, and if cells look more like healthy cells than cancerous cells. GI NET grades include:
There are several ways to treat GI NET. Healthcare providers will recommend treatment based on your cancer’s grade, treatment side effects, your overall health and your personal preferences. Treatments include active surveillance, surgery and medical treatments.
Providers may recommend active surveillance if the tumor is growly very slowly and isn’t likely to spread to other areas of your body. Active surveillance includes:
Surgery for gastrointestinal endocrine tumors depends on the tumor’s location and if it’s spread to other areas of your body.
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Regardless of your specific surgery to treat your GI NET, it’s essential that your surgery team knows you have carcinoid syndrome, a set of symptoms that are signs of neuroendocrine tumors. If you have carcinoid syndrome, surgery may trigger potentially life-threatening complications. When your surgeon knows you have this condition, they’ll use special medication before, during and after your surgery to prevent complications. Common GI NET surgeries include:
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All of these surgeries may have significant side effects. In some cases, you may need additional help at home as you recover from your surgery. Ask your healthcare provider what you can expect after your specific surgery.
It may. In most cases, your surgery will involve removing part of your digestive tract. This could affect your lifestyle, from how and what you eat to how you go to the bathroom. Your surgeon will explain exactly how surgery may affect you and what they’ll do to help you manage your digestive tract issues.
Healthcare providers may combine surgery with some of these treatments:
Each of these treatments affects people in different ways. Ask your healthcare provider to explain each treatment’s benefits and side effects so you understand how each one may affect you. Your healthcare provider will consider your overall health and your personal preferences when recommending treatment.
Unfortunately, there’s no known way to prevent GI NET. Medical researchers have discovered some links between certain hereditary syndromes and/or medical conditions that may increase your risk of developing neuroendocrine tumors. Talk to your healthcare provider about your medical history and your family’s medical history. They may recommend specific tests to monitor for early signs of GI NET so they can catch and treat tumors early on.
Your prognosis, or expected outcome, may depend on when a tumor was diagnosed and treated. Approximately 97% of people with GI NET who received treatment before the tumor spread were alive five years after diagnosis. That five-year survival rate drops to 95% if the tumor spreads to nearby tissues or lymph nodes. Approximately 67% of people whose GI NET spread outside of their digestive tracts were alive five years after diagnosis.
GI NET can come back. Depending on the tumor’s size, grade and location, you may have regular follow-up tests. For example, your provider may recommend you have annual CT scans for the first three years after treatment and annual physicals every year. Ask your healthcare provider about follow-up visits and tests for your specific situation.
You’ll likely need surgery if you have a gastrointestinal neuroendocrine tumor. Surgeons typically use open incisions rather than laparoscopic surgery. That means you may need to stay in the hospital for several days and then recover at home for several weeks.
You may have a regular follow-up schedule so your healthcare provider can check for signs your cancer has come back. Ask your surgeon what post-surgery symptoms may be signs of a serious issue. You should seek immediate medical care if you experience any of the following:
A note from Cleveland Clinic
Gastrointestinal neuroendocrine tumor (GI NET) may be a life-changing illness. That’s because most people with this condition need surgery that removes part or all of their digestive tracts. Your surgery may change how you eat or go to the bathroom. Your healthcare providers know it’s not always easy to make these changes. If you have concerns, share them with your provider. They’ll understand your situation and help you find solutions.
Last reviewed on 01/10/2023.
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