Know the symptoms of carcinoid syndrome

You can start by knowing what to look for and learning how to treat these symptoms.

Up to 40% of people with NETs will develop carcinoid syndrome

Diagnosis of carcinoid syndrome can take a long time, as the symptoms of carcinoid syndrome mimic the symptoms of many other more common medical conditions.

In some cases, it can take doctors several years to determine that the symptoms you are experiencing are due to the development of carcinoid syndrome.

The symptoms of carcinoid syndrome may be the first indication that a tumor has developed.

Why it’s critical to speak to a carcinoid/NET specialist

If you suspect that you’re experiencing symptoms of carcinoid syndrome, seek the guidance of a carcinoid/NET specialist.

These physicians have the greatest expertise and experience in diagnosing, treating, and following patients with these rare diseases.

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Starting a conversation with your doctor about the symptoms you are experiencing may be difficult.

Here is a guide for more productive conversations.

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Carcinoid syndrome can be difficult to diagnose because the symptoms are similar to other more common conditions.

Carcinoid syndrome is caused by excess serotonin and other chemicals that are secreted by tumor cells. Your doctor may first administer a 24-hour urine test or blood test to determine the levels of a metabolite of serotonin called 5-HIAA.

The urine test is different than most urine tests, and is quite involved, as your urine will need to be collected and monitored for 24-hours.

Since the level of serotonin in urine can vary depending based on a person’s activities, stress level, and even diet, measuring 5-HIAA is considered by some more useful than measuring serotonin levels overall. A test of blood levels of 5-HIAA can substitute for the urine test.

Clinical tests used to diagnose and monitor carcinoid syndrome

5-HIAA (5-Hydroxyindoleacetic Acid) Test

A urine or blood test that measures the level of the serotonin metabolite, 5-HIAA, in the body over a 24-hour period. In the case of the urine test, the level of 5-HIAA is monitored over a 14-hour period.

Elevated levels of 5-HIAA suggest a neuroendocrine tumor is present.

You will be advised to avoid foods like bananas, walnuts, pineapple, tomatoes, eggplant, kiwi fruit and plums before taking this test since these foods contain serotonin.

Certain medications and foods need to be avoided.

Chromogranin A (CgA) Test

Blood tests that detect proteins found in neuroendocrine cells that are often secreted into the blood in excessive amounts and are considered “markers” of carcinoid.

Gallium-68 PET/CT DOTATATE scan with NETSPOT™

This is a newly approved diagnostic tool.

Gallium-68 dotatate is a radioactive substance, used with PET/CT scans.

Because Gallium-68 attaches to neuroendocrine tumor cells, it can help detect the location and extent of tumors with greater precision than other tests.

Other diagnostic tests

Your doctor may suggest other tests, such as a biopsy of the suspected tumor or imaging tests like a computed tomography (CT) scan, magnetic resonance imaging (MRI), iodine-123-meta-iodobenzylguanidine scan (MIBG), or endoscopic ultrasonography.

Pancreastatin Test, Substance P and Neurokinin A Tests

These tests are often performed every 3-6 months to monitor tumor progression or regression as a result of treatment.

Somatostatin Receptor Scintigraphy (SRS) Test (Octreoscan)

A full-body imaging test that can help to reveal the location and growth of neuroendocrine tumors.

In this test a radioactive agent is injected into the bloodstream. This agent attaches to tumor cells that have receptors for somatostatin. An imaging device detects the radioactive agent and takes pictures of where that agent has attached within the body. This shows doctors the location of the tumor.