Provide a valuable resource to your clients or customers by linking to this resource page. Just place the following link on your website.
Carcinoid tumors are a rare type of slow-growing cancer that begins in the neuroendocrine cells, which are found throughout the body. Carcinoid syndrome is the collection of severe symptoms that occur when these tumors release excessive amounts of hormones, such as serotonin, into the bloodstream.
read more about carcinoid syndrome carcinoid tumours ...Carcinoid tumors typically originate in the gastrointestinal tract (stomach, small intestine, appendix, or colon) or in the lungs. Most tumors do not cause symptoms until they have metastasized (spread) to the liver, at which point the released hormones cause the distinct syndrome.
Symptoms include episodes of sudden flushing of the face and neck, persistent diarrhea, and wheezing or shortness of breath. The flushing can be triggered by stress, alcohol, or certain foods. Abdominal pain and heart valve damage can occur as the disease progresses. Fatigue and weight loss are also common in advanced stages. Because the symptoms overlap with other conditions, diagnosis often requires specific blood and imaging tests.
The connection lies in the uncontrolled release of hormones like serotonin. Since the liver usually filters these hormones, their entry into the general bloodstream in high amounts causes the widespread symptoms associated with the syndrome.
Carcinoid syndrome can directly impact eye health by causing severe and sustained conjunctival injection (redness or dilation of blood vessels in the whites of the eyes). Severe, frequent flushing episodes can cause the blood vessels on the eye's surface to become prominent and permanently visible.
Management involves a combination of strategies. Tumors are treated with surgery, chemotherapy, or targeted therapies. The severe hormonal symptoms of the syndrome are managed with medications like somatostatin analogs, which help block the release of the excess hormones.
Yes, carcinoid tumors are cancerous, but they are often slow-growing compared to many other types of cancer.
No, while flushing is characteristic, persistent diarrhea and wheezing are also major symptoms that define the syndrome.
No, the syndrome only occurs when the tumors have spread, typically to the liver, bypassing the body's filtering system.
If you experience unexplained "facial flushing" that lasts for minutes, see a doctor. This flushing can sometimes cause visible "telangiectasias" (spider veins) on the cheeks and eyelids. A 24-hour urine test for 5-HIAA is often used for diagnosis.
National Cancer Institute. Neuroendocrine Tumors (cancer.gov). 2025.
American Cancer Society. GI Tumors (cancer.org). 2025.
Mayo Clinic. Carcinoid Syndrome (mayoclinic.org). 2025.
Cleveland Clinic. Carcinoid Syndrome (clevelandclinic.org). 2023.