A carcinoid tumor (neuroendocrine tumor) is a slow-growing type of cancer that starts in neuroendocrine cells. Carcinoid tumors produce extra amounts of certain hormones and chemicals in your body. That can cause symptoms and syndromes. Treatment is often successful and may involve surgery, medications, chemotherapy or radiation.
A carcinoid tumor is a type of slow-growing cancer that starts in neuroendocrine cells. It’s a type of neuroendocrine tumor (NET).
Neuroendocrine cells are found throughout your body, especially your gastrointestinal (GI or digestive) system. They help your body produce hormones and control the release of digestive juices.
Like other types of cells, neuroendocrine cells can change and become cancerous, growing out of control. This forms a carcinoid tumor.
Carcinoid tumors can start in many parts of your body, most often in your ileum (lower section of your small intestine). But they also occur in your:
Even though carcinoid tumors are slow-growing, they can spread to other organs.
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The excess chemicals produced by carcinoid tumors can produce symptoms, which is called carcinoid syndrome. Only about 10% of people with carcinoid tumors develop carcinoid syndrome.
People with certain medical conditions are more likely to develop a carcinoid tumor:
Carcinoid tumors affect about 4 of every 100,000 adults. They’re even rarer in children.
Carcinoid tumors are a type of cancer, which means they’re malignant.
Researchers don’t know what triggers the cell growth that causes carcinoid tumors. They have, however, linked them to inherited syndromes, including:
The symptoms of a carcinoid tumor depend on:
Many carcinoid tumors don’t cause any symptoms, especially at first. But signs may appear when excess chemicals cause symptoms or when a tumor spreads (metastasizes).
One of the most common symptoms is flushing on your face and neck. Your skin may suddenly become red and hot. Flushing may be triggered by stress, alcohol and certain foods.
Other symptoms may include:
A carcinoid tumor also can lead to certain syndromes:
Carcinoid tumors often are found by accident when people are getting tests for other conditions. For example, a healthcare provider may find a carcinoid tumor during:
But if a healthcare provider suspects you have a carcinoid tumor based on flushing or other symptoms, they may order:
Based on the test results, your healthcare provider may classify or grade the carcinoid tumor. One way to classify a tumor is by location:
Your healthcare provider also might grade a tumor based on how likely it is to spread.
Treatment may involve a combination of strategies, including:
There aren’t any known ways to prevent carcinoid tumors. But scientists suspect smoking increases the risk of this type of cancer. Avoiding tobacco products or quitting smoking may help prevent the disease.
Carcinoid tumors generally have a better outlook than other types of cancer. But prognosis depends on many factors, including:
Carcinoid, or neuroendocrine, tumors can be life-threatening, particularly when cancer spreads to distant areas of your body. Metastatic (spread out) disease has a poorer prognosis than localized disease.
Carcinoid tumors can come back, even after successful treatment. You should have regular follow-up appointments to check for signs and symptoms of a neuroendocrine tumor. Catching cancer early can improve treatment options and effectiveness.
If you have a carcinoid tumor, ask your healthcare provider for a detailed plan for treatment and beyond, including:
A note from Cleveland Clinic
A carcinoid tumor (neuroendocrine tumor) is a type of slow-growing cancer that starts in neuroendocrine cells. It’s most common in the small intestine but can occur in many other places in your body. Treatment may involve a combination of strategies, including surgery and chemotherapy. Your healthcare provider will talk with you about your best treatment options.
Last reviewed by a Cleveland Clinic medical professional on 02/04/2022.
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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