Endocrine Abstracts

Introduction: Neuroendocrine tumours (NETs) are rare, slow-growing malignancies, often arising in the gastrointestinal tract and pancreas. Disease- and treatment-related factors such as malabsorption, reduced oral intake, and metabolic disturbances contribute to malnutrition, sarcopenia, and micronutrient deficiencies, which adversely affect quality of life, treatment tolerance, and survival. There are no established evidence-based nutritional guidelines for this population.

Objective: To map existing evidence on dietary interventions for adults with NETs, describe the types and outcomes of interventions studied, and identify gaps to inform clinical practice and research.

Methods: Following the JBI methodology and Arksey & O’Malley framework, a comprehensive search of Web of Science, OVID Medline, CINAHL Plus, and PubMed was conducted in July 2023. Eligible studies included adults with NETs receiving any dietary intervention, such as dietary advice, supplementation, pancreatic enzyme replacement therapy (PERT), or enteral/parenteral nutrition. Outcomes including survival, nutritional status, weight, or biochemical markers were also included in the search terms. Studies in children, non-empirical literature, or those not specific to NETs were excluded. Screening was performed independently by two reviewers, with data charted and synthesised using descriptive and thematic analysis.

Results: From 463 records, six observational studies (n = 439 gastroenteropancreatic NET patients) were included, most from the UK. Interventions included vitamin/mineral supplementation, home parenteral nutrition (HPN), PERT, and adherence to a Mediterranean diet. Reported outcomes were survival, weight changes, nutritional status, and biochemical markers. HPN and PERT were associated with improved survival and nutritional parameters; vitamin D and B12 supplementation corrected deficiencies and improved bone health markers. Most studies were small (mean sample size 73), heterogeneous, and rarely used validated nutritional assessment tools. Evidence was limited to biomedical interventions, with no qualitative or patient-reported outcomes and little exploration of oral nutritional support or enteral feeding.

Conclusions: Dietary interventions in NETs show potential clinical benefits, but current evidence is sparse, small-scale, and methodologically limited. There is a need for dietitian-led research incorporating diverse NET subtypes, robust nutritional assessment, and mixed-methods designs to develop evidence-based nutrition care strategies.

Keywords: Neuroendocrine tumours; dietary intervention; nutrition; scoping review