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Updated: May 21, 2026
A Model for Perineural Invasion in Head and Neck Squamous Cell Carcinoma
Published on: January 5, 2017
Urinary 5-HIAA excretion is not increased in patients with head and neck paragangliomas
Leonie T van Hulsteijn1, Nicolette van Duinen, Johannes A Romijn
1Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden - the Netherlands. L.T.van_Hulsteijn@lumc.nl
Background:
Case reports have documented carcinoid-like features in head and neck paragangliomas (HNPGLs), which, in addition to catecholamine storing granules, may also contain granules with serotonin. Serotonin is metabolized to 5-hydroxyindoleacetic acid (5-HIAA).
Aim:
To assess the urinary excretion rates of 5-HIAA and catecholamines in HNPGL patients.
Methods:
In 114 consecutive HNPGL patients, normetanephrine, metanephrine, norepinephrine, epinephrine, VMA, dopamine, 3-methoxytyramine and 5-HIAA excretion rates were measured in two 24-hour urinary samples. Increased excretion rates were defined as an increase of the average hormone excretion rate of 2 urine samples above the reference range. In all patients with catecholamine excess, intrathoracic and abdominal paragangliomas were excluded by 123I-MIBG scintigraphy, MRI and/or CT. Genetic screening for mutations in genes of the succinate dehydrogenase (SDH) family was performed.
Results:
Mean urinary 5-HIAA excretion rate was 14±9 μmol/24 hours (reference range 10-44 μmol/24 hours). Urinary 5-HIAA excretion was slightly increased in only 1 patient (48 μmol/24 hours). None of the 50 patients (44%) with increased urinary excretion rates of catecholamines and/or their metabolites had elevated 5-HIAA excretion.
Conclusion:
Urinary 5-HIAA excretion is within the normal reference range in almost all HNPGL patients. Therefore, this parameter has no clinical relevance in the routine clinical assessment of HNPGL patients.
