A gastrointestinal (GI) carcinoid tumor—also referred to as a gastrointestinal endocrine tumor—is a type of cancer that develops in the lining of the gastrointestinal (digestive) tract. Part of the body’s digestive system, the gastrointestinal tract digests foods and absorbs nutrients before passing waste material out of the body. GI carcinoid tumors form when neuroendocrine cells, which help control digestive juices and the muscles that facilitate digestion, grow and divide uncontrollably. These tumors may be found in multiple components of the gastrointestinal tract, including the stomach, appendix, small intestine and rectum.
Like most types of cancer, early detection is key when it comes to effective gastrointestinal carcinoid tumor treatment. If diagnosed at an early stage when it is still contained within the digestive tract, this cancer is generally highly treatable. However, if it has spread to nearby tissues, lymph nodes or other organs, it may be more difficult to treat. GI carcinoid tumors are often discovered unexpectedly during routine procedures for other conditions, as noticeable symptoms may not develop until the cancer has reached an advanced stage.
What are the signs of gastrointestinal carcinoid tumors?
Gastrointestinal carcinoid tumors tend to grow slowly and may not produce noticeable symptoms in early stages. When symptoms develop, they can vary according to the specific location of the tumor and stage of the cancer. For example, tumors in the small intestine may cause abdominal discomfort, while rectal tumors can lead to constipation and bleeding. In general, though, GI carcinoid tumors are often associated with:
- Nausea and vomiting
- Trouble passing stool due to bowel blockages
- Abdominal pain
- Rectal pain or bleeding
Some GI carcinoid tumors release hormone-like substances that can create additional symptoms. About 10% of tumors produce enough hormones to cause Carcinoid syndrome, a condition characterized by:
- Severe diarrhea
- Accelerated heartbeat
- Redness or warmth around the face (skin flushing)
Cushing syndrome is another possible byproduct of a GI carcinoid tumor, causing hormone-related symptoms that may involve:
- High blood pressure
- Increased blood sugar or diabetes
- Weight gain
- An increased amount of fat around the back of the neck
- Additional facial and body hair
- Muscle weakness
Who is at risk for gastrointestinal carcinoid tumors?
More than 10,000 Americans are diagnosed with gastrointestinal carcinoid tumors every year. This cancer occurs in people of various ages and backgrounds, but researchers have identified certain risk factors that may increase the likelihood of developing a GI carcinoid tumor. These risk factors include:
- Digestive health. Having certain gastrointestinal conditions, including atrophic gastritis, pernicious anemia and Zollinger-Ellison syndrome, may increase the likelihood of carcinoid tumors.
- Race. For reasons unknown, carcinoid tumors are more common among African Americans than Caucasians.
- Genetics. Neuroendocrine tumors are more prevalent in people with certain genetic syndromes, including multiple endocrine neoplasia type 1 and neurofibromatosis type 1.
- Tobacco use. Smoking cigarettes can increase the risk of carcinoid tumors and many other types of cancer.
- Older age. Carcinoid tumors are more common in older adults than children or young adults.
Individuals who do not have any established risk factors should still be mindful of changes in their digestive health and promptly speak with a physician about their symptoms.
How are gastrointestinal carcinoid tumors treated?
Each patient’s ideal course of gastrointestinal carcinoid tumor treatment will depend on the tumor’s location, stage and hormone production. Tumors that are detected at an early stage are often completely removed through surgery. In some cases, a portion of an affected organ is surgically removed along with the tumor. When only a portion of the tumor can be removed, surgery may be combined with chemotherapy or radiation therapy to help destroy remaining cancer cells and reduce symptoms. Because GI carcinoid tumors typically grow very slowly, complete resection of the tumor isn’t always necessary to achieving a successful outcome.
GI carcinoid tumors that have spread (metastasized) to the liver require more extensive treatment. Surgery to remove cancerous growths or a section of the liver may be recommended for patients who are healthy enough to undergo surgery. In other cases, techniques such as radiofrequency ablation, chemotherapy, embolization or targeted therapies may be used to slow the progression of disease and improve quality of life.
Our approach to gastrointestinal carcinoid tumor treatment
Patients who have been diagnosed with a gastrointestinal carcinoid tumor or believe they may have symptoms can find the highly specialized care they need at Moffitt Cancer Center. The experts in our Gastrointestinal Oncology Program have an unparalleled level of experience in treating complex GI carcinoid tumors, as Moffitt sees a high volume of patients with this cancer every year. Patients in our GI cancer program have access to a multispecialty team that includes:
- Medical oncologists
- Radiation oncologists
- Endoscopy specialists
- Pain intervention specialists
Our GI carcinoid tumor specialists meet regularly as a tumor board to discuss complex cases and refine treatment plans as necessary, ensuring the best possible outcomes and quality of life for our patients.
Furthermore, Moffitt has been designated a Comprehensive Cancer Center by the National Cancer Institute—the only cancer center based in Florida to have earned this distinction. We offer a full spectrum of progressive treatments for gastrointestinal carcinoid tumors, which range from minimally invasive GI procedures and novel chemotherapy combinations to breakthrough clinical trials and compassionate supportive care.