Management of Diarrhea in Patients With Carcinoid Syndrome

Functioning neuroendocrine tumors (NET): Minimum requirements for a NET specialist

INTRODUCTION AND AIMS

Functioning neuroendocrine tumors (f-NETs) represent a minority of all NETs, however their management is challenging due to the impact on patients' survival and quality of life. In addition to f-NETs, paraneoplastic syndromes (PNS) are due to substances that are not related to the primary anatomical site, they can develop in different phases of NETs evolution, and might complicate the patient's clinical course. Dedicated guidelines are still scanty. We aim to review available literature on f-NETs to propose a useful tool for clinicians in order to improve the diagnostic process and the management.

METHODS

Narrative review focused on f-NETs.

RESULTS

The most common f-NETs include insulinomas, gastrinomas and carcinoid syndrome (CS)- associated NETs. Symptoms related to hormone production may overlap with other common endocrine and gastrointestinal disorders, highlighting the pivotal role of multidisciplinary management. Somatostatin analogs (SSAs) represent the gold standard first-line treatment of most f-NETs, often followed by or combined with other treatments (surgery, liver-directed therapies, targeted therapies, peptide receptor radionuclide therapy). Paraneoplastic syndromes can develop in different phases of NET evolution and might complicate the patient's clinical course and response to therapy.

CONCLUSIONS

The management of hormonal syndromes is challenging and must be based on the multidisciplinary approach. Herein, we pointed out the minimal requirements for a NET specialist in the diagnosis and treatment of f-NETs. Efforts should be made to improve the awareness of functioning forms, to understand their pathogenesis and to improve their management.

Efficacy of Racecadotril in a Patient Affected by a Therapy-Refractory VIPoma and Carcinoid Syndrome

Neuroendocrine neoplasms (NENs) encompass a heterogeneous spectrum of tumors originating from the diffuse neuroendocrine cell system. Approximately 30% of NEN exhibit functional activity with clinical syndromes through hormone-mediated effects. Synchronous and metachronous functioning syndromes, resulting from the simultaneous release of distinct hormones, are exceptionally rare. Of note, hormonal excess syndromes can have a greater effect on patients' morbidity and mortality than the tumor mass itself. We present the case of a 49-year-old male patient affected by an oligo-metastatic ileal NEN, concurrently demonstrating vasointestinal peptide (VIP) and serotonin excretion, complicated by pulmonary tuberculosis. After the first cycle of Lutetium-177-DOTATATE peptide-radio-receptor therapy, the patient developed a severe watery diarrhea, hypokalemia, and achlorhydria (WDHA) syndrome, despite receiving high-dose somatostatin analogues, everolimus, and telotristat ethyl, without any surgical options. The WDHA syndrome necessitated intensive-care-unit (ICU) admission with continual intravenous administration of electrolytes and fluids. With limited alternatives, an off-label intervention using the enkephalinase inhibitor racecadotril was initiated. After 5 days of treatment, the WDHA syndrome exhibited sufficient control, facilitating the patient's discharge from the ICU. This case report underscores racecadotril as an individualized, off-label treatment strategy for patients with severe VIPoma and serotonin-driven WDHA syndrome, where conventional therapeutic avenues have been exhausted.

Update in the management of gastroenteropancreatic neuroendocrine tumors

Neuroendocrine neoplasms are a diverse group of neoplasms that can occur in various areas throughout the body. Well-differentiated neuroendocrine tumors (NETs) most often arise in the gastrointestinal tract, termed gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Although GEP-NETs are still uncommon, their incidence and prevalence have been steadily increasing over the past decades. The primary treatment for GEP-NETs is surgery, which offers the best chance for a cure. However, because GEP-NETs are often slow-growing and do not cause symptoms until they have spread widely, curative surgery is not always an option. Significant advances have been made in systemic and locoregional treatment options in recent years, including peptide-receptor radionuclide therapy with α and β emitters, somatostatin analogs, chemotherapy, and targeted molecular therapies.

An update on the safety of lanreotide autogel for the treatment of patients with neuroendocrine tumors

INTRODUCTION

Neuroendocrine neoplasms (NENs) are a rare group of tumors originating from neuroendocrine cells in various organs. They include neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs), which differ in biological behavior and prognosis. NETs are usually well-differentiated and slow-growing, while NECs are poorly differentiated and more aggressive. Management of NETs often involves somatostatin analogs like octreotide and lanreotide to control tumor growth and alleviate symptoms, especially in well-differentiated NETs. Lanreotide is used to control tumor growth, and both lanreotide and octreotide alleviate symptoms. Treatment approaches may vary depending on the specific type and grade of the neuroendocrine neoplasm.

AREAS COVERED

This review provides an update on the safety of lanreotide autogel in treating patients with NETs, through a comprehensive review of clinical trials, post-marketing surveillance, real-world evidence, and its safety profile. Specific adverse events, side effects, and potential risks associated with lanreotide autogel are discussed, along with risk mitigation strategies and recommendations for patient monitoring.

EXPERT OPINION

The findings highlight the overall safety of lanreotide autogel in managing NETs, focusing on its efficacy in controlling hormone secretion, tumor progression, and symptom management. New safety concerns and precautions are also addressed to help healthcare providers make informed decisions when prescribing lanreotide autogel.

A Case Report of Dermatofibrosarcoma Protuberans and Refractory Hypomagnesemia: Unveiling a Paraneoplastic Syndrome

Dermatofibrosarcoma protuberans (DFSP) is a rare, locally aggressive soft tissue sarcoma of the skin. DFSP typically presents as an asymptomatic, firm plaque in its earliest stage, gradually enlarging over months to years. This case report delineates a singular instance involving a 66-year-old female patient previously diagnosed with and treated for DFSP. The individual presented with a recurrent history of hospital admissions, manifesting symptoms of loose stools, generalised weakness, and diminished appetite. Investigations revealed persistent hypomagnesemia. The patient was treated with magnesium correction. Eventually, all complaints were resolved, and the patient was discharged satisfactorily. This case report aims to elucidate an exceptional correlation between DFSP and hypomagnesemia, characterised as its paraneoplastic syndrome (PNS). This study intends to comprehensively outline the clinical manifestations, diagnostic approaches, and therapeutic interventions pertaining to this distinct association.

Molecular biology of carcinoid heart disease: Seeking therapeutic targets in the era of targeted therapy

Carcinoid tumors (CT) are among the least studied tumors. It is a relatively rare and slow-growing tumor with good survival in its primary form. However, metastatic carcinoid tumor comes up with many different complications contributing to increased morbidity and mortality. Metastatic form of the disease has a wide spectrum of clinical manifestations and multisystem involvement including cardiovascular manifestations, neurological manifestations, and psychiatric manifestations and so on. In this review, we are centered towards the cardiovascular manifestations of the disease, which, by far, is one of the commonest causes of death in these patients. Being a neuroendocrine tumor, cardiovascular manifestations are mainly because of biologically active substances, produced by the tumor cells, remodeling the heart. Development of targeted therapies against carcinoid heart diseases is currently limited by lack of understanding of pathophysiology of the disease processes. In this review, we aim to figure out the spectrum of carcinoid heart diseases, along with the molecular biology of the changes going on, which, in turn, will not only pave a way to the development of targeted therapies but will also extend opportunities for molecular screening of the tumor and diagnosis at an early stage, thereby, reducing the morbidity and mortality.

Consideration of quality-of-life in the treatment decision-making for patients with advanced gastroenteropancreatic neuroendocrine tumors

INTRODUCTION

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a complex and heterogenous family of solid malignancies that originate from neuroendocrine tissue in the gastrointestinal tract or pancreas. Most patients diagnosed with GEP-NETs present with advanced or metastatic disease, and quality of life (QoL) is often an important priority when selecting treatments for these patients. Patients with advanced GEP-NETs often experience a substantial and persistent symptom burden that undermines their QoL. Addressing a patient's individual symptoms through judicious selection of treatment may improve QoL.

AREAS COVERED

The objectives of this narrative review are to summarize the impact of advanced GEP-NETs on patient QoL, assess the potential value of current treatments for maintaining or improving patient QoL, and offer a clinical framework for how these QoL data can be translated to inform clinical decision-making for patients with advanced GEP-NETs.

EXPERT OPINION

Patients with advanced GEP-NETs experience a significant and persistent symptom burden that impacts their daily lifestyle, activities, work life, and financial health, leading to erosion of their QoL. Ongoing and future studies incorporating longitudinal QoL assessments and head-to-head treatment evaluations will further inform the incorporation of QoL into clinical decision-making.

Neuroendocrine neoplasms of the lung and gastrointestinal system: convergent biology and a path to better therapies

Neuroendocrine neoplasms (NENs) can develop in almost any organ and span a spectrum from well-differentiated and indolent neuroendocrine tumours (NETs) to poorly differentiated and highly aggressive neuroendocrine carcinomas (NECs), including small-cell lung cancer (SCLC). These neoplasms are thought to primarily derive from neuroendocrine precursor cells located throughout the body and can also arise through neuroendocrine transdifferentiation of organ-specific epithelial cell types. Hence, NENs constitute a group of tumour types that share key genomic and phenotypic characteristics irrespective of their site of origin, albeit with some organ-specific differences. The establishment of representative preclinical models for several of these disease entities together with analyses of human tumour specimens has provided important insights into crucial aspects of their biology with therapeutic implications. In this Review, we provide a comprehensive overview of the current understanding of NENs of the gastrointestinal system and lung from clinical and biological perspectives. Research on NENs has typically been siloed by the tumour site of origin, and a cross-cutting view might enable advances in one area to accelerate research in others. Therefore, we aim to emphasize that a better understanding of the commonalities and differences of NENs arising in different organs might more effectively inform clinical research to define therapeutic targets and ultimately optimize patient care.

Pathogen-driven gene expression patterns lead to a novel approach to the identification of common therapeutic targets

Developing a common medication strategy for disease control and management could be greatly beneficial. Investigating the differences between diseased and healthy states using differentially expressed genes aids in understanding disease pathophysiology and enables the exploration of protein-drug interactions. This study aimed to find the most common genes in diarrhea-causing bacteria such as Salmonella enterica serovar Typhimurium, Campylobacter jejuni, Escherichia coli, Shigella dysenteriae (CESS) to find new drugs. Thus, differential gene expression datasets of CESS were screened through computational algorithms and programming. Subsequently, hub and common genes were prioritized from the analysis of extensive protein-protein interactions. Binding predictions were performed to identify the common potential therapeutic targets of CESS. We identified a total of 827 dysregulated genes that are highly linked to CESS. Notably, no common gene interaction was found among all CESS bacteria, but we identified 3 common genes in both Salmonella-Escherichia and Escherichia-Campylobacter infections. Later, out of 73 protein complexes, molecular simulations confirmed 5 therapeutic candidates from the CESS. We have developed a new pipeline for identifying therapeutic targets for a common medication strategy against CESS. However, further wet-lab validation is needed to confirm their effectiveness.

Neuroendocrine Tumors: A Comprehensive Review on Nutritional Approaches

Neuroendocrine neoplasms are a heterogeneous group of neoplasms with increasing incidence, high prevalence, and survival worldwide. About 90% of cases are well differentiated forms, the so-called neuroendocrine tumors (NETs), with slow proliferation rates and prolonged survival but frequent development of liver metastases and endocrine syndromes. Both the tumor itself and systemic therapy may have an impact on patient nutrition. Malnutrition has a negative impact on outcome in patients with NETs, as well as obesity. In addition, obesity and metabolic syndrome have been shown to be risk factors for both the development and prognosis of NET. Therefore, dietary assessment based on body composition and lifestyle modifications should be an integral part of the treatment of NET patients. Nutrition plans, properly formulated by a dietician, are an integral part of the multidisciplinary treatment team for patients with NETs because they allow an improvement in quality of life, providing a tailored approach based on nutritional needs and nutritional manageable signs and/or symptoms related to pharmacological treatment. The aim of this review is to condense the latest evidence on the role of the most used dietary models, the Mediterranean diet, the ketogenic diet, and intermittent fasting, in the context of NETs, while considering the clinical and molecular mechanisms by which these dietary models act.

Gastroenteropancreatic Neuroendocrine Tumors

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are the most common type of neuroendocrine tumors and are being increasingly identified in clinical practice. The diagnosis, staging, management, and surveillance of GEP-NETs rely heavily on endoscopy, and consequently, it is important for gastroenterologists to have a solid understanding of these tumors. This article reviews the presentation, diagnosis, and management of both localized and advanced GEP-NETs, with increased emphasis on the role of endoscopy, to enable gastroenterologists and other practitioners to have the necessary tools for the care of patients with these tumors.

A double-blind clinical trial to compare the efficacy and safety of a multiple amino acid-based ORS with the standard WHO-ORS in the management of non-cholera acute watery diarrhea in infants and young children: "VS002A" trial protocol

BACKGROUND

Diarrhea is the second deadliest disease for under-five children globally and the situation is more serious in developing countries. Oral rehydration solution (ORS) is being used as a standard treatment for acute watery diarrhea for a long time. Our objective is to compare the efficacy of amino acid-based ORS "VS002A" compared to standard glucose-based WHO-ORS in infants and young children suffering from acute non-cholera watery diarrhea.

METHODS

It is a randomized, double-blind, two-cell clinical trial at Dhaka Hospital of icddr,b. A total of 312 male children aged 6-36 months old with acute non-bloody watery diarrhea are included in this study. Intervention arm participants get amino acid-based ORS (VS002A) and the control arm gets standard glucose-based WHO-ORS. The primary efficacy endpoint is the duration of diarrhea in the hospital.

DISCUSSION

Oral rehydration therapy (ORT) with the present ORS formulation has certain limitations - it does not reduce the volume, frequency, or duration of diarrhea. Additionally, the failure of present standard ORS to significantly reduce stool output likely contributes to the relatively limited use of ORS by mothers as they do not feel that ORS is helping their child recover from the episode of diarrhea. Certain neutral amino acids (e.g., glycine, L-alanine, L-glutamine) can enhance the absorption of sodium ions and water from the gut. By using this concept, a shelf-stable, sugar-free amino acid-based hydration medicinal food named 'VS002A' that effectively rehydrates, and improves the barrier function of the bowel following infections targeting the gastrointestinal tract has been developed. If the trial shows significant benefits of VS002A use, this may provide evidence to support consideration of the use of VS002A in the present WHO diarrhea management guidelines. Conversely, if there is no evidence of benefit, these results will reaffirm the current guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04677296 . Registered on December 21, 2020.

Enterochromaffin Cells-Gut Microbiota Crosstalk: Underpinning the Symptoms, Pathogenesis, and Pharmacotherapy in Disorders of Gut-Brain Interaction

Disorders of gut-brain interaction (DGBIs) are common conditions in community and clinical practice. As specialized enteroendocrine cells, enterochromaffin (EC) cells produce up to 95% of total body serotonin and coordinate luminal and basolateral communication in the gastrointestinal (GI) tract. EC cells affect a broad range of gut physiological processes, such as motility, absorption, secretion, chemo/mechanosensation, and pathologies, including visceral hypersensitivity, immune dysfunction, and impaired gastrointestinal barrier function. We aim to review EC cell and serotonin-mediated physiology and pathophysiology with particular emphasis on DGBIs. We explored the knowledge gap and attempted to suggest new perspectives of physiological and pathophysiological insights of DGBIs, such as (1) functional heterogeneity of regionally distributed EC cells throughout the entire GI tract; (2) potential pathophysiological mechanisms mediated by EC cell defect in DGBIs; (3) cellular and molecular mechanisms characterizing EC cells and gut microbiota bidirectional communication; (4) differential modulation of EC cells through GI segment-specific gut microbiota; (5) uncover whether crosstalk between EC cells and (i) luminal contents; (ii) enteric nervous system; and (iii) central nervous system are core mechanisms modulating gut-brain homeostasis; and (6) explore the therapeutic modalities for physiological and pathophysiological mechanisms mediated through EC cells. Insights discussed in this review will fuel the conception and realization of pathophysiological mechanisms and therapeutic clues to improve the management and clinical care of DGBIs.

Perioperative Carcinoid Crisis: A Systematic Review and Meta-Analysis

Simple Summary

Intraoperative carcinoid crisis (CC) is thought to be a potentially lethal complication for patients with neuroendocrine tumors (NET). Though perioperative octreotide is often recommended for prevention, recent NET society guidelines raised concerns regarding limited data supporting the use of perioperative octreotide to prevent CC. The aim of our meta-analysis was to evaluate the existing evidence characterizing CC and the efficacy of prophylactic octreotide. We found that CC occurs frequently in patients having midgut NETs surgery, specifically those with NET liver metastasis, and is associated with worse postoperative outcomes. Our findings did not show a decreased risk in CC with prophylactic octreotide and questioned the advantage of routine prophylactic octreotide.

Abstract

Background: Surgery is the only curative option for patients with neuroendocrine tumors (NET) and is also indicated for debulking of liver metastasis. Intraoperative carcinoid crisis (CC) is thought to be a potentially lethal complication. Though perioperative octreotide is often recommended for prevention, recent NET society guidelines raised concerns regarding limited data supporting its use. We sought to evaluate existing evidence characterizing CC and evaluating the efficacy of prophylactic octreotide. Methods: A systematic review was performed on studies including patients having surgery for well-differentiated NET and/or NET liver metastasis (2000–2021), and reporting data on the incidence, risk factors, or prognosis of CC, and/or use of prophylactic octreotide. Meta-analysis was performed using random-effects models. Results: Eight studies met inclusion criteria (n = 943 operations). The pooled incidence of CC was 19% (95% CI [0.06–0.36]). Liver metastasis (odds ratio 2.85 [1.49–5.47]) and gender (male 0.58 [0.34–0.99]) were the only significant risk factors. The occurrence of CC was associated with increased risk of major postoperative complications (2.12 [1.03–4.35]). The use of prophylactic octreotide was not associated with decreased risk of CC (0.73 [0.32–1.66]). Notably, there was no standard prophylactic octreotide strategy used. Conclusions: Intraoperative carcinoid crisis is a common complication occurring in up to 20% of patients with midgut NET and/or liver metastasis undergoing surgery. Prophylactic octreotide may not provide an efficient way to prevent this complication. Future studies should focus on prospective evaluation of well-defined prophylactic protocols using a standardized definition for CC.

Bile Acid Malabsorption in Patients with Neuroendocrine Tumors

BACKGROUND

Chronic diarrhea in patients with neuroendocrine tumors (NET) may be caused by bioactive products of NET, bile acid malabsorption (BAM), ileal resection (IR) or steatorrhea.

AIM

To quantitate BA and fat malabsorption in NET with diarrhea.

METHODS

Part of evaluation in medical oncology clinical practice, 67 patients [42F, 25 M; median age 64.0 y (17.0 IQR)] with well-differentiated NET and diarrhea underwent clinically indicated measurements of 48-h fecal BA [(FBA), fecal weight (normal < 400 g/48 h), fecal fat (normal < 7 g/day) in n = 52] and fasting serum 7αC4 (marker of hepatic BA synthesis, n = 30) between 01/2018 and 11/2020. IR had been performed in 45 patients. BAM diagnosis was based on FBA criteria: elevated total FBA (> 2337 µmol/48 h) or > 10% primary FBA or combination > 4% primary FBA plus > 1000 µmol total FBA/48 h. We also measured fecal elastase (for pancreatic insufficiency) in 13 patients.

RESULTS

BAM was present in 48/52 (92%) patients with NET. There were significant correlations between total FBA and 48-h fecal weight (R_s = 0.645, P < 0.001). Mean length of IR was 47 cm; in patients with IR < 25 cm, total FBA was elevated in 85% and primary FBA > 10% in 69%. In 22 patients with no IR, 13/15 tested (87%) had BAM. Among 6 patients with pancreatic NET and no IR, 80% had BAM. Fecal fat was ≥ 15 g/day in 18/42 (43%). In 4/17 (24%) with IR < 25 cm and 8/19 (42%) patients with IR > 25 cm fecal fat was 44.0 (40.5) and 38.0 (38.0)g/day, respectively.

CONCLUSION

A majority of patients with NET and diarrhea had BAM, even with < 25 cm or no IR.

Vitamin D deficiency and tumor aggressiveness in gastroenteropancreatic neuroendocrine tumors

PURPOSE

Data regarding vitamin D status in patients affected by gastroenteropancreatic (GEP) neuroendocrine tumor (NET) are limited and often showing contrasting results. The aim of the study was to evaluate the incidence of vitamin D deficiency (<20 ng/mL) in GEP-NET patients and compare the 25-hydroxyvitamin D (25(OH)D) levels with clinicopathological parameters and clinical outcome.

METHODS

A retrospective cross-sectional study including 75 low grade (G1-G2) GEP-NETs and 123 healthy controls matched for age, sex, and body mass index, was performed.

RESULTS

GEP-NET patients had significantly lower 25(OH)D levels compared to controls (17.9 ± 7.8 vs 24.2 ± 7.7 ng/mL, p < 0.0001). Ileal NETs were associated to lower 25(OH)D levels compared to other primary tumor sites (p = 0.049) and small bowel resection posed a significant increased risk of severe vitamin D deficiency (OR = 2.81, 95% CI = 1.25-3.37, p = 0.018). No correlation with somatostatin analogs treatment was found. 25(OH)D levels were significantly lower in G2 compared to G1 GEP-NETs (15.6 ± 7.8 vs 19.9 ± 7.4 ng/mL, p = 0.016) and in patients with progressive disease (12.6 ± 5.7 ng/mL) compared to those with stable disease (mean 21.5 ± 8.2 ng/mL, p = 0.001) or tumor free after surgery (19.6 ± 7.3 ng/mL, p = 0.002). Patients with vitamin D deficiency and insufficiency had shorter progression-free survival compared to those with sufficiency (p = 0.014), whereas no correlation was found with disease-specific survival.

CONCLUSIONS

Vitamin D deficiency is highly prevalent among GEP-NETs and could be associated with high tumor grade and disease progression. Therefore, the monitoring of 25(OH)D levels is relevant in these patients and vitamin D supplementation should be considered in the management of GEP-NET patients with vitamin D deficiency or insufficiency.

A Systematic Review of Economic and Quality-of-Life Research in Carcinoid Syndrome

BACKGROUND

To date, the economic burden and patient-reported outcomes associated with carcinoid syndrome (CS) in patients with neuroendocrine tumor (NET) remain largely unknown.

OBJECTIVES

The objective of this study was to perform a systematic review of economic and quality-of-life (QOL) studies related to the treatment of CS.

METHODS

Articles included in the review were extracted from PubMed, Embase, and the Cochrane Library. Studies had to be in English and published between 1 January 2000 and 2 July 2020. Other study eligibility criteria included patients with NET with CS receiving treatment for CS, study outcomes of cost or QOL, and clinical trials or population-based studies using claims or other secondary databases. The interventions included somatostatin analogs, telotristat ethyl, or other treatment for CS. To evaluate the quality and bias of the included studies, the 24-item CHEERS and 10-item Gill and Feinstein checklists were used. We report a narrative synthesis of the findings from the selected studies.

RESULTS

A total of 12 economic and 12 QOL studies met the inclusion criteria and were included for review. Patients with uncontrolled CS symptoms had 23-92% higher costs than those with controlled CS; mostly, ambulatory/outpatient services were the primary drivers of the costs. The use of telotristat ethyl may be cost effective if the societal willingness to pay is as high as $US150,000 per quality-adjusted life-year in the USA. Of the 12 QOL papers, only three case-control studies assessed QOL at baseline and more than two follow-up time points. Seven studies evaluated QOL at two or more time points but lacked a control group, obscuring direct intervention effects on patients' well-being.

CONCLUSIONS

We observed wide variations in the reviewed studies evaluating the economic burden and patient-reported outcomes, in terms of cost and QOL, of patients with CS. Although QOL is consistently impaired and costs are consistently increased by CS, the numbers of both cost and QOL studies among this patient population remain sparse, and many of the existing studies indicated an important need for quality improvement.

Weight Maintenance up to 48 Weeks in Patients With Carcinoid Syndrome Treated With Telotristat Ethyl: Pooled Data From the Open-Label Extensions of the Phase III Clinical Trials TELESTAR and TELECAST

Reported incidences of neuroendocrine tumors (NETs) appear to be increasing, possibly due to greater disease awareness and increased accuracy of diagnosis. Approximately 20% of patients with NETs develop carcinoid syndrome (CS), which arises from elevated secretion of bioactive compounds, including serotonin, from NETs. This leads to symptoms including diarrhea and flushing, which result in weight loss and are associated with considerable negative impact on patients' quality of life. We previously reported significant weight gain and improved nutritional status in patients with NETs who were treated with telotristat ethyl (TE) for 12 weeks. In this follow-up analysis, using pooled data from the 36-week open-label extensions of the TELESTAR (NCT01677910) and TELECAST (NCT02063659) phase III trials, we demonstrate that improvements in weight and nutritional parameters were sustained or further improved in patients with CS through to week 48 of treatment with TE. At week 48/end of study, 68.7% of all patients maintained a stable weight or had weight gain and the mean changes from baseline in cholesterol and albumin levels in patients treated with TE were +0.41 mmol/L and -0.34 g/L, respectively. These results indicate that TE, alongside routine clinical practice, may provide long-term benefits in nutritional intake and weight evolution in patients with CS.

Opportunities to Improve Symptom Control with Somatostatin Congeners in GEP-NETs: A Review of Key Issues

Octreotide acetate (octreotide) is the most prescribed and most studied somatostatin congener, or analog, for gastroenteropancreatic neuroendocrine tumors (GEP‐NETs) and carcinoid syndrome, the latter of which may be characterized by debilitating diarrhea and flushing. Approved in the U.S. more than 30 years ago, octreotide is widely used to control the symptoms of carcinoid syndrome and has been shown to demonstrate antiproliferative activity. The two formulations available in the U.S. include a subcutaneous immediate‐release (IR) injection introduced in 1989 and a long‐acting repeatable (LAR) intramuscular injection approved in 1999. Lanreotide depot (lanreotide), a more recent somatostatin congener, has been available in the U.S. since 2014.

Despite widespread use of octreotide LAR, several key challenges exist with the current depot‐based treatment paradigm. Studies indicate that LAR formulations are associated with continued unmet patient needs, owing in part to a loss of bioactivity over time that may necessitate progressive supplemental treatment with IR octreotide to adequately control symptoms. Clinicians should understand the key differences in the pharmacokinetic profiles of the LAR and IR formulations that may contribute to bioactivity loss and somatostatin receptor desensitization. In addition, there is a need to re‐evaluate the role of IR octreotide in combination with depot therapy to provide consistent bioavailability and better control of carcinoid syndrome symptoms.

The purpose of this review is to explore all these issues and to re‐establish a rationale for the IR formulation, particularly with respect to novel use cases and its use during the COVID‐19 pandemic.

This review explores key challenges with depot‐based treatment of gastroenteropancreatic neuroendocrine tumors with octreotide and the key differences between the LAR and IR formulations.

Can an amino acid mixture alleviate gastrointestinal symptoms in neuroendocrine tumor patients?

Background

Neuroendocrine tumors, although relatively rare in incidence, are now the second most prevalent gastrointestinal neoplasm owing to indolent disease biology. A small but significant sub-group of neuroendocrine tumor patients suffer from diarrhea. This is usually secondary to carcinoid syndrome but can also be a result of short gut syndrome, bile acid excess or iatrogenic etiologies. Recently, an amino acid based oral rehydration solution (enterade Advanced Oncology Formula) was found to have anti-diarrheal properties in preclinical models.

Methods

A retrospective chart review of all NET patients treated with enterade AO was performed after IRB approval.

Results

Ninety-eight NET patients who had received enterade AO at our clinic from May 2017 through June 2019 were included. Patients (N=49 of 98) with follow up data on bowel movements (BMs) were included for final analysis. Eighty-four percent of patients (41/49) had fewer BMs after taking enterade AO and 66% (27/41) reported more than 50% reduction in BM frequency. The mean number of daily BMs was 6.6 (range, 320) at baseline before initiation of therapy, while the mean number of BMs at 1 week time point post enterade AO was 2.9 (range, 011).

Conclusions

Our retrospective observations are encouraging and support prospective validation with appropriate controls in NET patients. This is first published report of the potential anti-diarrheal activity of enterade AO in NET patients.

Effects of care bundles for patients with pressure ulcers and the impact on self-care efficacy

OBJECTIVE

To investigate the effects of care bundles for patients with pressure ulcers and the impact on self-care efficacy.

METHOD

A total of 160 patients with pressure ulcers were enrolled and divided into two groups using a lottery method. The control group (n=80) was cared for with routine nursing while the observation group (n=80) was additionally nursed with care bundles for 3 months. Both groups were compared in terms of grading of pressure ulcers, self-care efficacy, pressure ulcer management, awareness rate, and quality of life.

RESULTS

At 3 months after nursing, the grading of pressure ulcers was significantly improved in both groups. The observation group exhibited higher incidence of pressure ulcers, unstageable and deep tissue injury than the control group (P<0.05). DSES scores were improved in both groups (P<0.05). Scores of daily living, health behavior, compliance behavior, and emotional management in the observation group were higher than those in the control group (P<0.05). The skills of pressure ulcer management were strengthened in both groups (P<0.05). Scores of nutritional support, repositioning, skin care, dressing changes, and pressure ulcer assessment in the observation group were higher than those in the control group (P<0.05). The observation group also exhibited higher scores in terms of diet, pressure ulcer monitoring, lesion staging, complications and knowledge of pressure ulcer triggers than the control group (P<0.05). Quality of life was significantly improved in both groups after 3 months of nursing. PH, RP, BP, GH, VT, SF, RE and MH scores in the observation group were higher than those in the control group (P<0.05).

CONCLUSION

Care bundles can improve pressure ulcer grading, enhance patient self-care efficacy and skills of pressure ulcer management, and help improve patient awareness rates and quality of life for patients with pressure ulcers, which is worth of promoting.

Hypomagnesemia in the Cancer Patient

Hypomagnesemia is a common medical problem that contributes to the morbidity and mortality of patients with cancer. This review summarizes magnesium physiology and highlights the mechanisms underlying magnesium disturbances due to cancer and cancer treatment. The causes of hypomagnesemia can be categorized according to the pathophysiologic mechanism: decreased intake, transcellular shift, gastrointestinal losses, and kidney losses. Patients with cancer are at risk for opportunistic infections, frequently experience cardiovascular complications, and often receive classes of medications that cause or exacerbate hypomagnesemia. Also, cancer-specific therapies are responsible for hypomagnesemia, including platinum-based chemotherapy, anti-EGF receptor mAbs, human EGF receptor-2 target inhibitors (HER2), and calcineurin inhibitors. Urinary indices, such as the fractional excretion of magnesium, can provide useful information about the etiology. The management of hypomagnesemia depends on the magnitude of hypomagnesemia and the underlying cause. We recommended checking serum magnesium at the beginning of treatment and as part of routine monitoring throughout cancer treatment. Opportunities exist for potential research and practice improvement, including further characterization of hypomagnesemia regarding the clinical effect on cancer outcomes, preventing hypomagnesemia in patients receiving high-risk anticancer agents, and developing effective therapeutic strategies.

Differential Diagnosis of Diarrhea in Patients With Neuroendocrine Tumors

Patients with neuroendocrine tumors (NETs) and carcinoid syndrome experience diarrhea that can have a debilitating effect on quality of life. Diarrhea also may develop in response to other hormonal syndromes associated with NETs, surgical complications, medical comorbidities, medications, or food sensitivities. Limited guidance on the practical approach to the differential diagnosis of diarrhea in these patients can lead to delays in appropriate treatment. This clinical review and commentary underscore the complexity in identifying the etiology of diarrhea in patients with NETs. Based on our collective experience and expertise, we offer a practical algorithm to guide medical oncologists and other care providers to expedite effective management of diarrhea and related symptoms in patients with NETs.

Differential diagnosis of diarrhoea in patients with neuroendocrine tumours: A systematic review

BACKGROUND

Approximately 20% of patients with neuroendocrine tumours (NETs) develop carcinoid syndrome (CS), characterised by flushing and diarrhoea. Somatostatin analogues or telotristat can be used to control symptoms of CS through inhibition of serotonin secretion. Although CS is often the cause of diarrhoea among patients with gastroenteropancreatic NETs (GEP-NETs), other causes to consider include pancreatic enzyme insufficiency (PEI), bile acid malabsorption and small intestinal bacterial overgrowth. If other causes of diarrhoea unrelated to serotonin secretion are mistaken for CS diarrhoea, these treatments may be ineffective against the diarrhoea, risking detrimental effects to patient quality of life.

AIM

To identify and synthesise qualitative and quantitative evidence relating to the differential diagnosis of diarrhoea in patients with GEP-NETs.

METHODS

Electronic databases (MEDLINE, Embase and the Cochrane Library) were searched from inception to September 12, 2018 using terms for NETs and diarrhoea. Congresses, systematic literature review bibliographies and included articles were also hand-searched. Any study designs and publication types were eligible for inclusion if relevant data on a cause(s) of diarrhoea in patients with GEP-NETs were reported. Studies were screened by two independent reviewers at abstract and full-text stages. Framework synthesis was adapted to synthesise quantitative and qualitative data. The definition of qualitative data was expanded to include all textual data in any section of relevant publications.

RESULTS

Forty-seven publications (44 studies) were included, comprising a variety of publication types, including observational studies, reviews, guidelines, case reports, interventional studies, and opinion pieces. Most reported on PEI on/after treatment with somatostatin analogs; 9.5%-84% of patients with GEP-NETs had experienced steatorrhoea or confirmed PEI. Where reported, 14.3%–50.7% of patients received pancreatic enzyme replacement therapy. Other causes of diarrhoea reported in patients with GEP-NETs included bile acid malabsorption (80%), small intestinal bacterial overgrowth (23.6%-62%), colitis (20%) and infection (7.1%). Diagnostic approaches included faecal elastase, breath tests, tauroselcholic (selenium-75) acid (SeHCAT) scan and stool culture, although evidence on the effectiveness or diagnostic accuracy of these approaches was limited. Assessment of patient history or diarrhoea characteristics was also reported as initial approaches for investigation. From the identified evidence, if diarrhoea is assumed to be CS diarrhoea, consequences include uncontrolled diarrhoea, malnutrition, and perceived ineffectiveness of CS treatment. Approaches for facilitating differential diagnosis of diarrhoea include improving patient and clinician awareness of non-CS causes and involvement of a multidisciplinary clinical team, including gastroenterologists.

CONCLUSION

Diarrhoea in GEP-NETs can be multifactorial with misdiagnosis leading to delayed patient recovery and inefficient resource use. This systematic literature review highlights gaps for further research on prevalence of non-CS diarrhoea and suitability of diagnostic approaches, to determine an effective algorithm for differential diagnosis of GEP-NET diarrhoea.

Differential Diagnosis and Management of Diarrhea in Patients with Neuroendocrine Tumors

Diarrhea is a recurrent symptom in patients with neuroendocrine tumors (NETs) and can represent different etiologies; thus, differential diagnosis is challenging. This paper distinguishes the different causes of chronic diarrhea in patients with gastroenteropancreatic NETs, with the aim to identify the most appropriate therapeutic approach. Underlying causes of diarrhea can be multifactorial, including not only diarrhea that is related to specific hormonal hypersecretory syndromes, but also diarrhea that is secondary to the following: extensive surgery which can cause pancreatic exocrine insufficiency or short bowel syndrome, treatment with somatostatin analogs or other antineoplastic agents, and bile acid malabsorption. After initial management of diarrhea with general treatments (dietary modification, use of antidiarrheals), a proper differential diagnosis is necessary to treat patients with specific etiology-driven therapeutic approaches, such as somatostatin analogs, pancreatic enzyme replacement therapy, and tryptophan hydroxylase inhibitors. In conclusion, NETs should be considered in the differential diagnosis of patients suffering from chronic diarrhea, after the exclusion of more common etiologies. Furthermore, physicians should keep in mind that several different etiologies might be responsible for diarrhea occurrence in NET patients. A prompt diagnosis of the actual cause of diarrhea is necessary to guide the treatment and a multidisciplinary approach is mandatory.

Prevention and Management of Hormonal Crisis during Theragnosis with LU-DOTA-TATE in Neuroendocrine Tumors. A Systematic Review and Approach Proposal

Neuroendocrine tumors (NETs) frequently overexpress somatostatin receptors (SSTR) on their cell surface. The first-line pharmacological treatment for inoperable metastatic functioning well-differentiated NETs are somatostatin analogs. On second line, Lu-DOTA-TATE (177Lu-DOTA0 Tyr 3 octreotate) has shown stabilization of the disease and an increase in progression free survival, as well as effectiveness in controlling symptoms and increasing quality of life. The management of functional NETs before and during LU-DOTA-TATE treatment is specially challenging, as several complications such as severe carcinoid and catecholamine crisis have been described. The aim of this review is to establish practical guidance for the management and prevention of the most common hormonal crises during radionuclide treatment with Lu-DOTA-TATE: carcinoid syndrome (CS) and catecholamine hypersecretion, as well as to provide a brief commentary on other infrequent metabolic complications. To establish a practical approach, a systematic review was performed. This systematic review was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and conducted using MEDLINE (accessed from PubMed), Google Scholar and ClinicalTrials.gov. Literature searches found 449 citations, and finally nine were considered for this systematic review.

Role of tryptophan-metabolizing microbiota in mice diarrhea caused by Folium sennae extracts

BACKGROUND

Although reports have provided evidence that diarrhea caused by Folium sennae can result in intestinal microbiota diversity disorder, the intestinal bacterial characteristic and specific mechanism are still unknown. The objective of our study was to investigate the mechanism of diarrhea caused by Folium sennae, which was associated with intestinal bacterial characteristic reshaping and metabolic abnormality.

RESULTS

For the intervention of Folium sennae extracts, Chao1 index and Shannon index were statistical decreased. The Beta diversity clusters of mice interfered by Folium sennae extracts were distinctly separated from control group. Combining PPI network analysis, cytochrome P450 enzymes metabolism was the main signaling pathway of diarrhea caused by Folium sennae. Moreover, 10 bacterial flora communities had statistical significant difference with Folium sennae intervention: the abundance of Paraprevotella, Streptococcus, Epulopiscium, Sutterella and Mycoplasma increased significantly; and the abundance of Adlercreutzia, Lactobacillus, Dehalobacterium, Dorea and Oscillospira reduced significantly. Seven of the 10 intestinal microbiota communities were related to the synthesis of tryptophan derivatives, which affected the transformation of aminotryptophan into L-tryptophan, leading to abnormal tryptophan metabolism in the host.

CONCLUSIONS

Folium sennae targeted cytochrome P450 3A4 to alter intestinal bacterial characteristic and intervene the tryptophan metabolism of intestinal microbiota, such as Streptococcus, Sutterella and Dorea, which could be the intestinal microecological mechanism of diarrhea caused by Folium sennae extracts.

The Neuroendocrine Neoplasms of the Digestive Tract: Diagnosis, Treatment and Nutrition

Nuroendocrine neoplasms (NENs) are a group of rare neoplasms originating from dispersed neuroendocrine cells, mainly of the digestive and respiratory tract, showing characteristic histology and immunoprofile contributing to classification of NENs. Some NENs have the ability to produce biogenic amines and peptide hormones, which may be associated with clinical syndromes like, e.g., the carcinoid syndrome caused by unmetabolized overproduced serotonin, hypoglycemic syndrome in case of insulinoma, or Zollinger-Ellison syndrome accompanying gastrinoma. Diagnostics for these include ultrasound with endoscopic ultrasound (EUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron-emission tomography/computed tomography (PET/CT). Different nuclear medicine procedures can also be used, like somatostatin analogues scintigraphy (SRS) and 68Ga-Dota-Peptide PET/CT, as well as biochemical methods to determine the level of general neuroendocrine markers, such as chromogranin A (CgA), 5-hydroxyindolacetic acid (5-HIAA), synaptopfysin and cell type-specific peptide hormones, and neurotransmitters like gastrin, insulin, serotonin, and histamine. NENs influence the whole organism by modulating metabolism. The treatment options for neuroendocrine neoplasms include surgery, somatostatin analogue therapy, radionuclide therapy, chemotherapy, molecular targeted therapies, alpha-interferon therapy, and inhibitors of serotonin production. In the case of hypersensitivity to biogenic amines, a diet that limits the main sources of amines should be used. The symptoms are usually connected with histamine, tyramine and putrescine. Exogenic sources of histamine are products that take a long time to mature and ferment. Patients with a genetic insufficiency of the diamine oxidase enzyme (DAO), and those that take medicine belonging to the group of monoamine oxidases (MAO), are particularly susceptible to the negative effects of amines. Diet plays an important role in the initiation, promotion, and progression of cancers. As a result of the illness, the consumption of some nutrients can be reduced, leading to nutritional deficiencies and resulting in malnutrition. Changes in metabolism may lead to cachexia in some patients suffering from NENs. The aim of this narrative review was to advance the knowledge in this area, and to determine possibilities related to dietary support. The authors also paid attention to role of biogenic amines in the treatment of patients with NENs. We can use this information to better understand nutritional issues faced by patients with gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs), and to help inform the development of screening tools and clinical practice guidelines.