Carcinoid syndrome
Flush syndrome; Argentaffinoma syndromeCarcinoid syndrome is a group of symptoms associated with carcinoid tumors. These are tumors most often of the small intestine, colon, appendix, or bronchial tubes in the lungs.
Causes
Carcinoid syndrome is the pattern of symptoms sometimes seen in people with carcinoid tumors. These tumors are rare, and often slow growing. Most carcinoid tumors are found in the gastrointestinal tract and lungs.
Carcinoid syndrome occurs in very few people with carcinoid tumors, after the tumor has spread to the liver or lung.
These tumors release too much of the hormone serotonin, as well as several other chemicals. The hormones cause the blood vessels to open (dilate). This causes carcinoid syndrome.
Serotonin
The serotonin test measures the level of serotonin in the blood.
Read Article Now Book Mark ArticleSymptoms
The carcinoid syndrome is made up of four main symptoms including:
- Flushing (face, neck, or upper chest), or widened blood vessels seen on the skin (telangiectasias)
Telangiectasias
Telangiectasias are small, widened blood vessels on the skin. They are usually harmless, but may be associated with several diseases.
Read Article Now Book Mark Article - Difficulty breathing, such as wheezing
- Diarrhea
- Heart problems, such as leaking heart valves, slow heartbeat, low or high blood pressure
Symptoms are sometimes brought on by physical exertion, or eating or drinking things such as blue cheese, chocolate, or red wine.
Exams and Tests
Most of these tumors are found when tests or procedures are done for other reasons, such as during abdominal surgery.
If a physical exam is done, the health care provider may find signs of:
- Heart valve problems, such as murmur
Murmur
A heart murmur is a blowing, whooshing, or rasping sound heard during a heartbeat. The sound is caused by turbulent (rough) blood flow through the h...
Read Article Now Book Mark Article - Niacin-deficiency disease (pellagra)
Pellagra
Pellagra is a disease that occurs when a person does not get enough niacin (one of the B complex vitamins) or tryptophan (an amino acid).
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Tests that may be done include:
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5-HIAA levels in urine
5-HIAA
5-HIAA is a urine test that measures the amount of 5-hydroxyindoleacetic acid (5-HIAA). 5-HIAA is a breakdown product of a hormone called serotonin....
Read Article Now Book Mark Article - Blood tests (including serotonin and chromogranin blood tests)
Serotonin
The serotonin test measures the level of serotonin in the blood.
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CT
MRI scan of the chest or abdomen
CT
A computed tomography (CT) scan is an imaging method that uses x-rays to create pictures of cross-sections of the body. Related tests include:Abdomin...
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A magnetic resonance imaging (MRI) scan is an imaging test that uses powerful magnets and radio waves to create pictures of the body. It does not us...
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Echocardiogram
Echocardiogram
An echocardiogram is a test that uses sound waves to create pictures of the heart. The picture and information it produces is more detailed than a s...
Read Article Now Book Mark Article - PET scan
Treatment
Surgery to remove the tumor is usually the first treatment. It can permanently cure the condition if the tumor is completely removed.
If the tumor has spread to the liver, treatment involves either of the following:
- Removing areas of liver that have tumor cells
- Sending (infusing) medicine directly into the liver to destroy the tumors
When the entire tumor can't be removed, removing large portions of the tumor ("debulking") can help relieve the symptoms.
Octreotide (Sandostatin) or lanreotide (Somatuline) injections are given to people with advanced carcinoid tumors that can't be removed with surgery.
People with carcinoid syndrome should avoid alcohol, large meals, and foods high in tyramine (aged cheeses, avocado, many processed foods), because they may trigger symptoms.
Some common medicines, like selective serotonin reuptake inhibitors (SSRIs), such as paroxetine (Paxil) and fluoxetine (Prozac), may make symptoms worse by increasing levels of serotonin. However, do not stop taking these medicines unless your provider tells you to do so.
Support Groups
Learn more about carcinoid syndrome and get support from:
- The Carcinoid Cancer Foundation -- www.carcinoid.org/resources/support-groups/directory/
- Neuroendocrine Tumor Research Foundation -- netrf.org/for-patients/
Outlook (Prognosis)
The outlook in people with carcinoid syndrome is sometimes different from the outlook in people who have carcinoid tumors without the syndrome.
Prognosis also depends on the site of tumor. In people with the syndrome, the tumor has usually spread to the liver. This lowers the survival rate. People with carcinoid syndrome are also more likely to have a separate cancer (second primary tumor) at the same time. Overall, the prognosis is usually excellent.
Possible Complications
Complications of carcinoid tumors may include:
- Increased risk of falls and injury (from low blood pressure)
-
Bowel obstruction (from tumor)
Bowel obstruction
Intestinal obstruction is a partial or complete blockage of the bowel. The contents of the intestine cannot pass through it.
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Gastrointestinal bleeding
Gastrointestinal bleeding
Gastrointestinal (GI) bleeding refers to any bleeding that starts in the gastrointestinal tract. Bleeding may come from any site along the GI tract, ...
Read Article Now Book Mark Article - Heart valve failure
A fatal form of carcinoid syndrome, carcinoid crisis, may occur as a side effect of surgery, anesthesia or chemotherapy.
When to Contact a Medical Professional
Contact your provider for an appointment if you have symptoms of carcinoid syndrome.
Prevention
Treating the tumor reduces the risk of carcinoid syndrome.
References
National Cancer Institute website. Gastrointestinal carcinoid tumors treatment (Adult) (PDQ) - health professional version. www.cancer.gov/types/gi-carcinoid-tumors/hp/gi-carcinoid-treatment-pdq. Updated August 19, 2022. Accessed October 13, 2022.
Öberg K. Neuroendocrine tumors and related disorders. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 45.
Wolin EM, Jensen RT. Neuroendocrine tumors. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 219.
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Serotonin uptake - illustration
Carcinoid syndrome is the pattern of symptoms that typically are exhibited by people with carcinoid tumors. The symptoms include bright red facial flushing, diarrhea, and occasionally wheezing. A specific type of heart valve damage can occur, as well as other cardiac problems. Carcinoid tumors secrete excessive amounts of the hormone serotonin. Surgery with complete removal of the tumor tissue is the ideal treatment. It can result in a permanent cure if it is possible to remove the tumor entirely.
Serotonin uptake
illustration
-
Serotonin uptake - illustration
Carcinoid syndrome is the pattern of symptoms that typically are exhibited by people with carcinoid tumors. The symptoms include bright red facial flushing, diarrhea, and occasionally wheezing. A specific type of heart valve damage can occur, as well as other cardiac problems. Carcinoid tumors secrete excessive amounts of the hormone serotonin. Surgery with complete removal of the tumor tissue is the ideal treatment. It can result in a permanent cure if it is possible to remove the tumor entirely.
Serotonin uptake
illustration
Review Date: 8/15/2022
Reviewed By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.