Patient education: Carcinoid syndrome (The Basics)

What is carcinoid syndrome? — Carcinoid syndrome is a group of symptoms that can happen when you have a type of cancer called a carcinoid tumor. These tumors are also called "neuroendocrine tumors." They can start growing in the digestive tract, lungs, or other parts of the body (figure 1 and figure 2). These tumors sometimes then spread to other parts of the body.

Carcinoid syndrome happens with some, but not all, neuroendocrine tumors. Most commonly, it happens when a neuroendocrine tumor that started in the small intestine spreads to the liver. Carcinoid syndrome happens because neuroendocrine tumors can make hormones and other substances. When the tumor has spread to the liver, these substances can get into the blood. When these substances get into the blood, they can travel around the body and cause symptoms.

What are the symptoms of carcinoid syndrome? — Symptoms can include:

●Episodes of "flushing" – Flushing is when your skin gets red or purple and feels hot. This is the most common symptom of carcinoid syndrome. An episode of flushing usually starts suddenly and lasts 30 seconds to 30 minutes. Flushing usually happens on the face, neck, or upper chest. Episodes can sometimes be triggered by certain things, such as eating a big meal or drinking alcohol.

●Spider veins, called "telangiectasias" – These are small, swollen veins that look like purple stripes or spots on the skin. They are usually on the nose, cheek, or upper lip.

●Watery diarrhea that is not bloody

●Wheezing (noisy breathing) or trouble breathing

Sometimes, neuroendocrine tumors cause a type of heart disease called "carcinoid heart disease," which affects the heart valves. Carcinoid heart disease doesn't always cause symptoms. When it does, it can cause swelling of the legs or trouble breathing, or make people feel tired.

Is there a test for carcinoid syndrome? — Yes. Your doctor or nurse will do an exam. They will also order tests to make sure you have carcinoid syndrome and look for neuroendocrine tumors in your body.

Tests can include:

●Urine tests – This involves collecting all of the urine you make for 24 hours. This is the test done most often to check whether carcinoid syndrome is the cause of your symptoms.

●Blood tests

●Imaging tests – Imaging tests create pictures of the inside of the body. They include CT and MRI scans, as well as other tests that involve injecting a special substance into the veins and then using a camera to take images of the body. These tests might be done to find the location of the carcinoid tumor that is causing your symptoms.

●Endoscopy – This is a procedure that lets the doctor look at the inside of your stomach and first part of your small intestine. The doctor will put a thin tube with a camera and light on the end in your mouth and down into your stomach (figure 3).

●Echocardiogram (also called an "echo") – This test uses sound waves to create pictures of your heart as it beats (figure 4).

How is carcinoid syndrome treated? — Treatment depends on your symptoms, where your neuroendocrine tumor or tumors are, and how much the cancer has spread in your body.

Some medicines help control your symptoms. They include:

●Medicines that block a neuroendocrine tumor from making the hormones or substances that cause symptoms

●Anti-diarrhea medicines

Other treatments aim to remove tumors or make them smaller, so they can't make as much of the substances that cause problems. They include:

●Surgery to remove all or part of a neuroendocrine tumor

●A procedure to block a neuroendocrine tumor's blood supply, called "embolization" – This is done only for tumors in the liver. During this procedure, the doctor blocks off the blood vessel that sends blood to the tumor.

●Ablation therapy – This is a procedure that can kill cancer cells. It does not involve surgery. It is done only for tumors in the liver. Doctors can do ablation therapy in different ways. For example, they can use heat or a laser to kill the cancer cells.

●Chemotherapy – Chemotherapy is the term doctors use for medicines that kill cancer cells or stop them from growing.

●Treatment for carcinoid heart disease – In some cases, this involves surgery to replace a diseased heart valve with a healthy heart valve.

●Lutetium Lu 177-Dotatate (brand name: Lutathera) – This is a medicine that delivers radiation directly into the tumor to kill the cancer cells. It is given through a thin tube that goes into your vein, called an "IV." This treatment is usually done for advanced neuroendocrine tumors, and might be used if other treatments do not work.

Is there anything I can do on my own to prevent flushing? — Maybe. If you find that certain things trigger your flushing, you can try to avoid those things. Triggers can include eating certain foods or drinking alcohol.

What else should I do? — It's important to follow all of your doctor's instructions about visits and tests. It's also important to talk to your doctor about any side effects or problems you have during treatment.

Getting treated for carcinoid syndrome involves making many choices, such as what treatment to have. Always let your doctors and nurses know how you feel about a treatment. Any time you are offered a treatment, ask:

●What are the benefits of this treatment? Is it likely to help me live longer? Will it reduce or prevent symptoms?

●What are the downsides of this treatment?

●Are there other options besides this treatment?

●What happens if I do not have this treatment?

More on this topic

Patient education: Diarrhea in teens and adults (The Basics)
Patient education: Upper endoscopy (The Basics)
Patient education: Echocardiogram (The Basics)

Patient education: Chronic diarrhea in adults (Beyond the Basics)