Neuroendocrine tumours and their microenvironment.

Tumours can escape the immune system by expressing programmed death-ligand-1 (PD-L1), which allows them to bind to PD-1 on T-cells and avoid recognition by the immune system. Regulatory T-cells (Tregs), indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) also play a role in immune suppression. Knowledge about the interaction of neuroendocrine tumours (NETs) with their immune microenvironment and the role of immunotherapy in patients with NET is scarce.

Quantitative Profiling of Platelet-Rich Plasma Indole Markers by Direct-Matrix Derivatization Combined with LC-MS/MS in Patients with Neuroendocrine Tumors.

Background: Currently, several indole markers are measured separately to support diagnosis and follow-up of patients with neuroendocrine tumors (NETs). We have developed a sensitive mass spectrometry method that simultaneously quantifies all relevant tryptophan-related indoles (tryptophan, 5-hydroxytryptophan, serotonin, 5-hydroxyindoleacetic acid) in platelet-rich plasma. Direct-matrix derivatization was used to make the chemical properties of the indoles uniform and to improve the analytical sensitivity and specificity of the assay.

Interlesional Heterogeneity of Metastatic Neuroendocrine Tumors Based on 18F-DOPA PET/CT.

Purpose: Neuroendocrine tumors (NETs) can produce neuroendocrine amines resulting in symptoms. Selecting the most active amine-producing tumor lesions for local treatment might be beneficial for patients with metastatic small intestinal NET. Tumor burden correlates with catecholamine pathway activity.

Web-based personalised information and support for patients with a neuroendocrine tumour: randomised controlled trial.

Background: Patients with a neuroendocrine tumour (NET) frequently have physical and psychosocial complaints. Aim of this study is to determine whether a web-based, personalised information and support system (WINS) reduces distress and/or improves patients' perception of and satisfaction with information received.

Methods: Patients with NET, stratified for those newly diagnosed (< 6 months, n = 28) and with a longer history of disease (n = 74), were randomised between standard care (n = 49) and intervention, consisting of access to WINS (n = 53).