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  5. 5-hydroxyindoleactic acid (5-HIAA)
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5-hydroxyindoleactic acid (5-HIAA)

  1. Home
  2. Cancer information
  3. Resources
  4. Glossary
  5. 5-hydroxyindoleactic acid (5-HIAA)
Print

Description

A substance produced when serotonin breaks down.

5-HIAA can be used as a tumour marker. It is used to look for tumours that start in cells of the neuroendocrine system or to monitor a person’s response to treatment for neuroendocrine tumours.

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