Some NETs increase the amount of serotonin in the body. Serotonin is a chemical the body makes that sends messages between different parts of the brain. It helps control lots of functions, such as how you sleep, your mood, and your appetite. The liver changes serotonin into a chemical called 5HIAA. The body then passes 5HIAA out through the urine.
You will be asked to save all the urine you pass in a 24-hour period. Your doctor will then test it for 5HIAA.
Certain foods, drinks and medicines can raise your levels of 5HIAA. You may need to avoid these for a few days before and during the urine collection.
If you have a NET, the levels of some chemicals in the blood may rise. This is mainly serotonin and a protein called chromogranin A (CgA). You will need to have blood samples taken to check the levels of these chemicals.
You will also have a blood test to count the number of healthy blood cells in your blood. This is called a full blood count or FBC. Another blood test will check how well your kidneys and liver are working.
Below is a sample of the sources used in our neuroendocrine tumours (NETs) information. If you would like more information about the sources we use, please contact us at firstname.lastname@example.org
Esmo clinical practice guidelines: endocrine and neuroendocrine cancers. Available from: www.esmo.org/guidelines/endocrine-and-neuroendocrine-cancers (accessed Nov 2017).
This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.
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