Web-based information and support for patients with a newly diagnosed neuroendocrine tumor:A feasibility study

Purpose: Patients with a neuroendocrine tumor (NET) frequently experience physical and psychosocial complaints. Novel strategies to provide information to optimize supportive care in these patients are of interest. The aim of this study was to examine whether the use of a web-based system consisting of self-screening of problems and care needs, patient education, and self-referral to professional health care is feasible in NET patients and to evaluate their opinion on this. Methods: Newly diagnosed NET patients were randomized between standard care (n = 10) or intervention with additional access to the web-based system (n = 10) during 12 weeks. Patients completed questionnaires regarding received information, distress, quality of life (QoL), and empowerment. The intervention group completed a semi-structured interview to assess patients' opinion on the web-based system. Results: The participation rate was 77% (20/26 invited patients) with no dropouts. The use of the web-based system had a negative effect on patients' perception and satisfaction of received information (range Cohen's d -0.88 to 0.13). Positive effects were found for distress (Cohen's d 0.75), global QoL (subscale European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30, Cohen's d 0.46), resolving problems with social functioning and finding information (subscales EORTC QLQ-GINET 21, Cohen's d 0.69, respectively, 1.04), and feeling informed (subscale empowerment questionnaire, Cohen's d 0.51). The interview indicated that the web-based system was of additional value to standard care. Conclusions: Use of this web-based system is feasible. Contradictory effects on informing and supporting NET patients were found and should be subject of further research

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. Here, we investigated the immune microenvironment of serotonin-producing (SP) and non-serotonin-producing NETs (NSP-NETs). Tumours of 33 patients with SP-NET and 18 patients with NSP-NET were studied. Immunohistochemical analyses were performed for PD-L1, T-cells, IDO, TDO, mismatch repair proteins (MMRp) and activated fibroblasts. PD-L1 expression was seen in <1% of tumour and T-cells. T-cells were present in 33% of NETs, varying between 1 and 10% T-cells per high power field. IDO was expressed in tumour cells in 55% of SP-NETs and 22% of NSP-NETs (p = 0.039). TDO was expressed in stromal cells in 64% of SP-NETs and 13% of NSP-NETs (p = 0.001). No tumours had loss of MMRp. TDO-expressing stromal cells also strongly expressed alpha-SMA and were identified as cancer-associated fibroblasts (CAFs). Factors that are associated with a response to checkpoint inhibitor treatment were absent or only present to a limited extent in the tumour microenvironment of NETs. The expression of IDO and TDO in a substantial part of NETs and the presence of CAFs suggest two mechanisms that could be responsible for the cold immune microenvironment, which should be explored to enhance anti-tumour immunity and clinical responses

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. METHODS: In situ derivatization was performed directly in platelet-rich plasma with propionic anhydride at an ambient temperature. The derivatized indoles were extracted by online solid-phase extraction and eluted to the analytical column for separation followed by mass spectrometric detection. The method was validated according to international guidelines. Platelet-rich plasma samples from 68 healthy individuals and 40 NET patients were analyzed for tryptophan, 5-hydroxytryptophan, serotonin, and 5-hydroxyindoleacetic acid. RESULTS: The method reproducibly quantified relevant indoles in 8.5 min, including online sample cleanup. Intra- and interassay imprecision, evaluated at 3 different concentrations, ranged from 2.0% to 12% and 1.9% to 13%, respectively. The limit of quantification was sufficient to measure endogenous concentrations of all 4 indoles. Healthy individuals and NET patients had different concentrations of 5-hydroxytryptophan, serotonin, and 5-hydroxyindoleacetic acid, but tryptophan concentrations were the same. CONCLUSIONS: Direct-matrix derivatization in combination with LC-MS/MS is a powerful tool for the simultaneous quantification of all tryptophan-related indoles in platelet-rich plasma. Simultaneous profiling of relevant indoles improves the biochemical characterization and follow-up of NETs

Capillary gravity waves on the free surface of an inviscid fluid of infinite depth. Existence of solitary waves

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. We analyzed interlesional heterogeneity with 18F-DOPA PET scans in patients with small intestinal NET and investigated if lesions with substantially higher 18F-DOPA uptake could be identified. Methods In this retrospective, observational study, the 18F-DOPA uptake was calculated by dividing SUVpeak of the lesion by the SUVmean of the background organ. The magnitude of heterogeneity between lesions within a patient was calculated by dividing the lesion with the highest by the one with the lowest 18F-DOPA uptake. Lesions with a higher 18F-DOPA uptake than the upper inner or outer fence (>1.5 or 3 times the interquartile range above the third quartile) were defined as lesions with mild or extreme high 18F-DOPA uptake, respectively, and presence of these was determined in patients with 10 lesions or more. Results 18F-DOPA was detected over 680 lesions in 38 patients, of which 35 were serotonin producing. 18F-DOPA uptake varied with a median of 8-fold up to 44-fold between lesions within a patient. In 12 of 20 evaluable patients, lesions with mild high 18F-DOPA uptake were found, and in 5, lesions with extreme high 18F-DOPA uptake. Conclusions 18F-DOPA-PET showed considerable heterogeneity in 18F-DOPA uptake between tumor lesions and identified lesions within patients with mild or extreme high 18F-DOPA uptake