Urine 5-HIAA and quality of life in neuroendocrine neoplasia. Is there an association?

Background To determine whether urine 5-HIAA (u5HIAA) concentrations correlate with health-related quality of life (HRQL) in patients with neuroendocrine neoplasms (NEN). Methods A retrospective single-centre cross-sectional study was conducted including 386 patients with histological or radiological diagnosis of NEN. Patients completed standardized questionnaires at clinic appointments. Spot u5HIAA concentrations were correlated with Patient Health Questionnaire-9 (PHQ-9) depression scores, Generalized Anxiety Disorder-7 (GAD-7) anxiety scores, European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) scores, and the Quality of Life Questionnaire Gastrointestinal Neuroendocrine Tumour Module 21 (QLQ-GINET21) scores. Correlation was evaluated with the Spearman rho test. Results 258 patients had completed HRQL data and corresponding u5HIAA available. Unknown primary sites and sites which do not typically secrete 5-HIAA (26 cases) were excluded in the analysis making a total of 232. One hundred and nineteen (51.3%) were male, 145 (62.5%) had a small intestine primary. Median age was 66 years and median u5HIAA was 7.8 µmol/mmol. Males had significantly higher u5HIAA (median:10.0, IQR: 5.6 – 15.4) compared to females (5.6, IQR: 3.3 - 11.3) (p=0.001). Males reported significantly higher Global Health Status (p=0.018) and lower GINET21 (p=0.001), GAD-7 (p=0.001) and PHQ-9 (p=0.009) scores. Within the overall cohort, there was a significant association between high u5HIAA and low GAD-7 (p=0.032); and between high u5HIAA and low GINET21 GI symptoms (p=0.024). No significant association was found between u5HIAA and PHQ-9 (p=0.383), QLQ GINET21 endocrine symptoms (p=0.197), EORTC QLQ-C30 Global Health Status (p=0.746) or diarrhoea score (p=0.305). Conclusion High circulating concentrations of serotonin may be associated with less anxiety in patients with NEN, further prospective studies are required to corroborate these results. Males had higher u5HIAA and fewer symptoms than females. The sex differences in 5-HIAA values and HRQL in this cohort warrant further investigation.