skip to main content
Main Site Navigation
Top of main content

What Is Carcinoid Syndrome?

Carcinoid syndrome is a disorder that occurs when small tumors (carcinoid tumors) make chemicals that get into the bloodstream. The chemicals cause various symptoms. These slow-growing tumors are mainly found in the gastrointestinal tract or lungs (bronchi). They occur in the appendix (most often); small bowel (20%); rectum (15%); bronchi (12%); esophagus, stomach, and colon (10%); and ovary, biliary tract, and pancreas (3%). People usually find out about the disorder when the tumors are very advanced and cause symptoms. This syndrome is rare and occurs in about 3 in 100,000 people.

What Causes Carcinoid Syndrome?

Carcinoid tumors can make chemicals called serotonin, bradykinin, and histamine. Tumors grow from special cells called neuroendocrine cells. The cause of the tumors isn’t clear.

What Are the Symptoms of Carcinoid Syndrome?

The main symptoms are skin flushing (75% to 90%), diarrhea, breathing problems, facial skin lesions, and at times, rapid heartbeat. Red-purple flushes usually start in the face and spread to the neck and upper trunk. Flushing lasts from a few minutes to hours. Flushes that last longer may be related to bronchial carcinoids. Emotion, alcohol, or foods may trigger flushes, but flushes may occur without warning. Dizziness, fast heartbeat (tachycardia), and low blood pressure (hypotension) may occur with flushing. Diarrhea occurs in more than 70% of people. It’s often related to bloating of the abdomen (belly). Breathing problems include contraction of smooth muscles in the bronchi (bronchospasm). The result is shortness of breath and wheezing.

How Is Carcinoid Syndrome Diagnosed?

The health care provider makes a diagnosis from the medical history, physical examination, chest X-rays, computed tomography (CT) of the abdomen, and laboratory tests. These tests measure levels of the chemicals produced by the tumor. Some foods and drugs can cause false higher levels. Bananas, pineapples, eggplant, avocados, and walnuts can do this. Drugs that can cause false elevations include acetaminophen, caffeine, guaifenesin, and reserpine. Before this test, people must have a restricted diet and avoid these drugs. Special tests may include using radioactive iodine to label somatostatin to find tumors. The health care provider may suggest seeing a specialist such as an endocrinologist and endocrine surgeon.

How Is Carcinoid Syndrome Treated?

Treating the syndrome means treating the tumor. Surgery may be done to remove the tumor. If surgery can’t remove widespread tumors, medicines may shrink tumors and control symptoms. These drugs include octreotide and interferon alfa. Hepatic artery embolization and heating or freezing tumor cells may be treatment options in some patients.

DOs and DON’Ts in Managing Carcinoid Syndrome:

  • DO avoid alcohol. It may cause flushing.
  • DO eat a well-balanced diet. Avoid large meals, which can trigger flushing.
  • DO keep track of what triggers flushing and avoid those triggers.
  • DO learn as much as you can about your illness.
  • DO find a support group if you think that would help.
  • DON’T ignore symptoms. Call your health care provider if your symptoms don’t improve or get worse with treatment. Call if you have new symptoms.
  • DON’T stop taking your medicine or change the dosage because you feel better unless your health care provider tells you to.
  • DON’T use any medicines (including over-the-counter and herbal products) without first asking your health care provider.

Contact the following sources:

  • American Association of Clinical Endocrinologists
    Tel: (904) 353-7878
  • American Gastroenterological Association
    Tel: (301) 654-2055
  • American Society of Clinical Oncology
    Tel: (703) 299-0150

Copyright © 2016 by Saunders, an imprint of Elsevier, Inc.

Ferri’s Netter Patient Advisor

Not sure which type of care is right for you?

We can help.