The role of proton pump inhibitors in the treatment of Zollinger-Ellison syndrome

Influence of the Microbiome Metagenomics and Epigenomics on Gastric Cancer

Gastric cancer (GC) is one of the major causes of cancer deaths worldwide. The disease is seldomly detected early and this limits treatment options. Because of its heterogeneous and complex nature, the disease remains poorly understood. The literature supports the contribution of the gut microbiome in the carcinogenesis and chemoresistance of GC. Drug resistance is the major challenge in GC therapy, occurring as a result of rewired metabolism. Metabolic rewiring stems from recurring genetic and epigenetic factors affecting cell development. The gut microbiome consists of pathogens such as H. pylori, which can foster both epigenetic alterations and mutagenesis on the host genome. Most of the bacteria implicated in GC development are Gram-negative, which makes it challenging to eradicate the disease. Gram-negative bacterium co-infections with viruses such as EBV are known as risk factors for GC. In this review, we discuss the role of microbiome-induced GC carcinogenesis. The disease risk factors associated with the presence of microorganisms and microbial dysbiosis are also discussed. In doing so, we aim to emphasize the critical role of the microbiome on cancer pathological phenotypes, and how microbiomics could serve as a potential breakthrough in determining effective GC therapeutic targets. Additionally, consideration of microbial dysbiosis in the GC classification system might aid in diagnosis and treatment decision-making, taking the specific pathogen/s involved into account.

Proton pump inhibitor use and appropriateness analysis: a snapshot from a secondary care hospital

Objectives

Proton pump inhibitors (PPIs) have become one of the most frequently prescribed drugs since their introduction 30 years ago. Effectiveness and safety profile of PPIs has led to their overutilization and has exposed patients to a number of potential risks. The objective of this study was to evaluate the use of PPIs in a secondary care hospital in the United Arab Emirates.

Methods

This prospective observational drug-utilization study was conducted in patients receiving treatment with PPIs and admitted to internal medicine wards of the study site. Electronic patient case records were reviewed and data on PPI prescribing was collected and analysed. Appropriateness of PPI use was assessed as per international guidelines.

Key findings

Out of 172 patients enrolled, 53.5% were females with median age of 57 years (34.3, 71.0). Four different PPIs were prescribed to study patients, pantoprazole (86.6%), esomeprazole (5.8%), rabeprazole (4.1%) and omeprazole (3.5%). Ninety-two (53.5%) patients were prescribed intravenous PPI, whereas 80 (46.5%) patients were given PPI in oral form. Overall, 103 (59.9%) patients had inappropriate PPI prescriptions. Of these inappropriate prescriptions, 22 patients had no clear indication for PPI use and for 16 patients; PPIs were indicated for stress ulcer prophylaxis in low-risk category. Corticosteroid use [odds ratio (OR): 4.34, 95% confidence interval (CI): 1.22–15.46; P = 0.023] was significantly associated with greater odds of inappropriate PPI use.

Conclusions

We report a high prevalence of inappropriate PPI prescribing among the hospitalized patients in our study. Inappropriate PPI prescribing is a concerning issue and collective efforts should be made to check and minimize the same.

The Chinese guidelines for the diagnosis and treatment of pancreatic neuroendocrine neoplasms (2020)

Abstract

Pancreatic neuroendocrine neoplasms (pNENs) are highly heterogeneous, and the management of pNENs patients can be intractable. To address this challenge, an expert committee was established on behalf of the Chinese Pancreatic Surgery Association, which consisted of surgical oncologists, gastroenterologists, medical oncologists, endocrinologists, radiologists, pathologists, and nuclear medicine specialists. By reviewing the important issues regarding the diagnosis and treatment of pNENs, the committee concluded evidence-based statements and recommendations in this article, in order to further improve the management of pNENs patients in China.

Gastrinomas: Medical or Surgical Treatment

This article reviews the role of surgical and medical management in patients with Zollinger-Ellison syndrome (ZES) due to a gastrin-secreting neuroendocrine tumor (gastrinoma). It concentrates on the status at present but also briefly reviews the changes over time in treatment approaches. Generally, surgical and medical therapy are complementary today; however, in some cases, such as patients with ZES and multiple endocrine neoplasia type 1, the treatment approach remains controversial.

The Zollinger-Ellison syndrome: is there a role for somatostatin analogues in the treatment of the gastrinoma?

PURPOSE

Analyze the role of somatostatin analogues (SSAs) in the treatment of sporadic and MEN1-related gastrinomas, trying to define whether recent trials have changed the landscape of gastrinoma therapy.

METHODS

We evaluate the rationale of SSA use in the treatment of gastrinomas, summarize the current literature concerning the effect of SSAs on the control of Zollinger-Ellison syndrome (ZES) and gastrinomas tumor progression and discuss their role in the most recent guidelines.

RESULTS

The medical treatment of gastrinoma and related ZES is aimed at controlling acid hypersecretion and tumor progression, in inoperable patients. The use of proton pump inhibitors (PPIs) to control the syndrome is a cornerstone in the ZES therapy. SSAs are not usually indicated for antisecretory purpose, because PPIs are considered the treatment of choice, due to their long lasting high efficacy and oral availability. The antiproliferative effect of SSAs has been established by two placebo-controlled trials that have clearly demonstrated a significant increase in progression free survival in patients affected by non-functioning well-differentiated advanced neuroendocrine tumors (NETs). The recent ENETS guidelines recommend the use of SSAs in advanced well differentiated NETs as antiproliferative agents.

CONCLUSIONS

The high sstr-expression in gastrinomas make them highly responsive to SSAs and support the use of such drugs to counteract the tumour growth in patients not amenable to surgical cure. Unfortunately, limited data, mainly case reports or small series, support the use of SSAs in advanced gastrinomas, therefore, it is difficult to quantify their ability to control tumour growth and disease progression.

Diagnosis of Zollinger-Ellison syndrome in the era of PPIs, faulty gastrin assays, sensitive imaging and limited access to acid secretory testing

In recent years the diagnosis of Zollinger-Ellison syndrome (ZES) has become increasingly controversial with several new approaches and criteria proposed, differing from the classical biochemical criterion of inappropriate hypergastrinemia (i.e., hypergastrinemia in the presence of hyperchlorhydria) (Table 1). These changes have come about because of the difficulty and potential dangers of stopping proton pump inhibitors (PPIs) for gastric acid analysis; the recognition than many of the current assays used to assess gastrin concentrations are unreliable; the development of sensitive imaging modalities that detect neuroendocrine tumors (NETs) including an increasing number of the primary gastrinomas; the increased use of percutaneous or endoscopic ultrasound (EUS)-directed biopsies/cytology and the general lack of availability of acid secretory testing. In this article we will discuss the basis for these controversies, review the proposed changes in diagnostic approaches and make recommendations for supporting the diagnosis of ZES in the modern era.

Effective and safe proton pump inhibitor therapy in acid-related diseases - A position paper addressing benefits and potential harms of acid suppression

BACKGROUND

The introduction of proton pump inhibitors (PPIs) into clinical practice has revolutionized the management of acid-related diseases. Studies in primary care and emergency settings suggest that PPIs are frequently prescribed for inappropriate indications or for indications where their use offers little benefit. Inappropriate PPI use is a matter of great concern, especially in the elderly, who are often affected by multiple comorbidities and are taking multiple medications, and are thus at an increased risk of long-term PPI-related adverse outcomes as well as drug-to-drug interactions. Herein, we aim to review the current literature on PPI use and develop a position paper addressing the benefits and potential harms of acid suppression with the purpose of providing evidence-based guidelines on the appropriate use of these medications.

METHODS

The topics, identified by a Scientific Committee, were assigned to experts selected by three Italian Scientific Societies, who independently performed a systematic search of the relevant literature using Medline/PubMed, Embase, and the Cochrane databases. Search outputs were distilled, paying more attention to systematic reviews and meta-analyses (where available) representing the best evidence. The draft prepared on each topic was circulated amongst all the members of the Scientific Committee. Each expert then provided her/his input to the writing, suggesting changes and the inclusion of new material and/or additional relevant references. The global recommendations were then thoroughly discussed in a specific meeting, refined with regard to both content and wording, and approved to obtain a summary of current evidence.

RESULTS

Twenty-five years after their introduction into clinical practice, PPIs remain the mainstay of the treatment of acid-related diseases, where their use in gastroesophageal reflux disease, eosinophilic esophagitis, Helicobacter pylori infection, peptic ulcer disease and bleeding as well as, and Zollinger-Ellison syndrome is appropriate. Prevention of gastroduodenal mucosal lesions (and symptoms) in patients taking non-steroidal anti-inflammatory drugs (NSAIDs) or antiplatelet therapies and carrying gastrointestinal risk factors also represents an appropriate indication. On the contrary, steroid use does not need any gastroprotection, unless combined with NSAID therapy. In dyspeptic patients with persisting symptoms, despite successful H. pylori eradication, short-term PPI treatment could be attempted. Finally, addition of PPIs to pancreatic enzyme replacement therapy in patients with refractory steatorrhea may be worthwhile.

CONCLUSIONS

Overall, PPIs are irreplaceable drugs in the management of acid-related diseases. However, PPI treatment, as any kind of drug therapy, is not without risk of adverse effects. The overall benefits of therapy and improvement in quality of life significantly outweigh potential harms in most patients, but those without clear clinical indication are only exposed to the risks of PPI prescription. Adhering with evidence-based guidelines represents the only rational approach to effective and safe PPI therapy. Please see related Commentary: doi: 10.1186/s12916-016-0724-1 .

Medical management of secretory syndromes related to gastroenteropancreatic neuroendocrine tumours

Although recent epidemiological evidence indicates that the prevalence of non-functioning gastroenteropancreatic (GEP) neuroendocrine tumours (NETs) is rising, a significant number of GEP-NETs still present with symptoms related to the secretion of biologically active substances leading to the development of distinct clinical syndromes. In the past, these syndromes were associated with substantial morbidity and mortality due to the lack of specific therapies; however, since the introduction of long-acting somatostatin analogues and medications such as proton pump inhibitors, their control has been greatly improved. As a result, nowadays, the main cause of morbidity and mortality in GEP-NETs is mostly directly related to tumour growth and the extent of metastatic disease. However, in some patients with functioning tumours and extensive disease, control of the secretory syndrome still remains problematic, necessitating the employment of several cytoreductive techniques, which may not always be sufficient. Recently, new agents directed against tumour growth, or exerting increased binding activity to receptors expressed in these tumours, or interfering with the synthetic pathway of some of the compounds secreted by these tumours, have been developed. Since there are no specific guidelines addressing the totality of the management of the secretory syndromes related to GEP-NETs, this review aims at critically analysing the medical management of previously recognised secretory syndromes; it also addresses areas of uncertainty, assesses the newer therapeutic developments and also addresses recently described but poorly characterised secretory syndromes related to GEP-NETs.

Weight Gain in Zollinger-Ellison Syndrome After Acid Suppression

OBJECTIVES

Zollinger-Ellison syndrome (ZES) is characterized by hypergastrinemia and gastric acid hypersecretion resulting in peptic ulcer disease, diarrhea, and weight loss. Acid secretion can be controlled with medication, and biochemical cure is possible with surgery. Data on how these interventions affect patients' weight are lacking. We aimed to determine how medical and surgical acid control affects weight over time.

METHODS

We performed a retrospective cohort study on 60 ZES patients. Acid control was achieved with appropriate-dose proton pump inhibitor (PPI) therapy. Surgery was performed for curative intent when appropriate. Weight change was assessed versus pre-acid control or immediate preoperative weights and expressed as absolute and percent change from baseline at 6, 12, 18, and 24 months.

RESULTS

A total of 30 PPI-controlled patients and 20 surgery-controlled patients were analyzed. Weight gain was noted at all time points while on appropriate-dose PPI therapy (P < 0.005). Of patients who had surgery with curative intent, weight gain was noted at 12 months (7.9%, P = 0.013) and 18 months (7.1%, P = 0.007). There was a trend toward weight gain seen at all time points in the patients who were surgically cured.

CONCLUSIONS

These data represent a novel description of weight gain after acid suppression in ZES.

Review of Proton Pump Inhibitor Overuse in the US Veteran Population

Objective: A growing body of evidence provides proof that proton pump inhibitors (PPIs) are overused in the general population and that such use is associated with adverse risks and unnecessary costs. Our objective was to systematically evaluate PPI overuse in the veteran population. Data Sources: A literature search using MEDLINE and CINHAL databases (1946-December 2014) was performed using the search term proton pump inhibitors coupled with each of the following key words: inappropriate use, misuse, and overuse. Searches were limited to studies and reviews in English language and human subjects. Additional references were identified from a review of literature citations. Study Selection and Data Extraction: All articles that centrally addressed the issue of PPI overuse were evaluated, following the PRISMA guidelines for systematic reviews. Data were extracted into Microsoft Excel 2013. Articles that focused on the pediatric or non-US veteran populations were excluded. Data Synthesis: Among 30 articles included, 5 evaluated PPI overuse in veterans. The reported prevalence rate of PPI overuse in veterans ranged from 33% to 67%. Several cases reported PPI-associated Clostridium difficile-associated diarrhea and pneumonia. One Veterans Affairs center reported the total cost of PPI overuse to be more than $200 000 based on over-the-counter costs and more than $1.5 million based on average wholesale price cost. Conclusions: PPI overuse is common among veterans and exposes them to adverse risks and costs the system enormous dollars. Based on the findings of this review, we provide recommendations to curb PPI overuse among veterans and in the Veterans Affairs system.

Diagnostic and Treatment Approaches for Refractory Peptic Ulcers

Refractory peptic ulcers are defined as ulcers that do not heal completely after 8 to 12 weeks of standard anti-secretory drug treatment. The most common causes of refractory ulcers are persistent Helicobacter pylori infection and use of nonsteroidal anti-inflammatory drugs (NSAIDs). Simultaneous use of two or more H. pylori diagnostic methods are recommended for increased sensitivity. Serologic tests may be useful for patients currently taking proton pump inhibitors (PPIs) or for suspected false negative results, as they are not affected by PPI use. NSAID use should be discontinued when possible. Platelet cyclooxygenase activity tests can confirm surreptitious use of NSAIDs or aspirin. Cigarette smoking can delay ulcer healing. Therefore, patients who smoke should be encouraged to quit. Zollinger-Ellison syndrome (ZES) is a rare but important cause of refractory gastroduodenal ulcers. Fasting plasma gastrin levels should be checked if ZES is suspected. If an ulcer is refractory despite a full course of standard PPI treatment, the dose should be doubled and administration of another type of PPI considered.

Causes of death and prognostic factors in multiple endocrine neoplasia type 1: a prospective study: comparison of 106 MEN1/Zollinger-Ellison syndrome patients with 1613 literature MEN1 patients with or without pancreatic endocrine tumors

Multiple endocrine neoplasia type 1 (MEN1) is classically characterized by the development of functional or nonfunctional hyperplasia or tumors in endocrine tissues (parathyroid, pancreas, pituitary, adrenal). Because effective treatments have been developed for the hormone excess state, which was a major cause of death in these patients in the past, coupled with the recognition that nonendocrine tumors increasingly develop late in the disease course, the natural history of the disease has changed. An understanding of the current causes of death is important to tailor treatment for these patients and to help identify prognostic factors; however, it is generally lacking.To add to our understanding, we conducted a detailed analysis of the causes of death and prognostic factors from a prospective long-term National Institutes of Health (NIH) study of 106 MEN1 patients with pancreatic endocrine tumors with Zollinger-Ellison syndrome (MEN1/ZES patients) and compared our results to those from the pooled literature data of 227 patients with MEN1 with pancreatic endocrine tumors (MEN1/PET patients) reported in case reports or small series, and to 1386 patients reported in large MEN1 literature series. In the NIH series over a mean follow-up of 24.5 years, 24 (23%) patients died (14 MEN1-related and 10 non-MEN1-related deaths). Comparing the causes of death with the results from the 227 patients in the pooled literature series, we found that no patients died of acute complications due to acid hypersecretion, and 8%-14% died of other hormone excess causes, which is similar to the results in 10 large MEN1 literature series published since 1995. In the 2 series (the NIH and pooled literature series), two-thirds of patients died from an MEN1-related cause and one-third from a non-MEN1-related cause, which agrees with the mean values reported in 10 large MEN1 series in the literature, although in the literature the causes of death varied widely. In the NIH and pooled literature series, the main causes of MEN1-related deaths were due to the malignant nature of the PETs, followed by the malignant nature of thymic carcinoid tumors. These results differ from the results of a number of the literature series, especially those reported before the 1990s. The causes of non-MEN1-related death for the 2 series, in decreasing frequency, were cardiovascular disease, other nonendocrine tumors > lung diseases, cerebrovascular diseases. The most frequent non-MEN1-related tumor deaths were colorectal, renal > lung > breast, oropharyngeal. Although both overall and disease-related survival are better than in the past (30-yr survival of NIH series: 82% overall, 88% disease-related), the mean age at death was 55 years, which is younger than expected for the general population.Detailed analysis of causes of death correlated with clinical, laboratory, and tumor characteristics of patients in the 2 series allowed identification of a number of prognostic factors. Poor prognostic factors included higher fasting gastrin levels, presence of other functional hormonal syndromes, need for >3 parathyroidectomies, presence of liver metastases or distant metastases, aggressive PET growth, large PETs, or the development of new lesions.The results of this study have helped define the causes of death of MEN1 patients at present, and have enabled us to identify a number of prognostic factors that should be helpful in tailoring treatment for these patients for both short- and long-term management, as well as in directing research efforts to better define the natural history of the disease and the most important factors determining long-term survival at present.

Pharmacotherapy of Zollinger-Ellison syndrome

INTRODUCTION

The role of pharmacotherapy in the management of patients with Zollinger-Ellison syndrome (ZES) is often equated with the medical management of acid hypersecretion. However, pharmacotherapy is also increasingly involved in the other management areas of these patients.

AREAS COVERED

This paper reviews the role of pharmacotherapy in all aspects of the management of patients with ZES. Newer aspects are emphasized. This includes the difficulty of diagnosing ZES in patients taking proton pump inhibitors. Also covered is the role of pharmacotherapy in controlling acid hypersecretion and other hormonal hypersecretory states these patients may develop, including hyperparathyroidism in patients with multiple endocrine neoplasia type 1 and ZES; tumor localization; and the treatment of advanced metastatic disease. The last includes chemotherapy, liver-directed therapies, biotherapy (somatostatin/interferon), peptide radio-receptor therapy and molecular-targeted therapies including the use of mTor inhibitors (everolimus) and tyrosine kinase inhibitors (sunitinib).

EXPERT OPINION

Pharmacotherapy is now involved in all aspects of the management of patients with ZES, with the result that ZES has progressed from being considered an entirely surgical disease initially to the present where medical treatment plays a major role in almost all aspects of the management of these patients.

Pancrelipase: an evidence-based review of its use for treating pancreatic exocrine insufficiency

Pancreatic exocrine insufficiency (PEI) is often observed in patients with pancreatic diseases, including chronic pancreatitis, cystic fibrosis, and tumors, or after surgical resection. PEI often results in malnutrition, weight loss and steatorrhea, which together increase the risk of morbidity and mortality. Therefore, nutritional interventions, such as low-fat diets and pancreatic enzyme replacement therapy (PERT), are needed to improve the clinical symptoms, and to address the pathophysiology of pancreatic exocrine insufficiency. PERT with delayed-release pancrelipase is now becoming a standard therapy for pancreatic exocrine insufficiency because it significantly improves the coefficients of fat and nitrogen absorption as well as clinical symptoms, without serious treatment-emergent adverse events. The major adverse events were tolerable gastrointestinal tract symptoms, such as stomach pain, nausea, and bloating. Fibrosing colonopathy, a serious complication, is associated with high doses of enzymes. Several pancrelipase products have been approved by the US Food and Drug Administration in recent years. Although many double-blind, placebo-controlled trials of pancrelipase products have been conducted in recent years, these studies have enrolled relatively few patients and have often been less than a few weeks in duration. Moreover, few studies have addressed the issue of pancreatic diabetes, a type of diabetes that is characterized by frequent hypoglycemia, which is difficult to manage. In addition, it is unclear whether PERT improves morbidity and mortality in such settings. Therefore, large, long-term prospective studies are needed to identify the optimal treatment for pancreatic exocrine insufficiency. The studies should also examine the extent to which PERT using pancrelipase improves mortality and morbidity. The etiology and severity of pancreatic exocrine insufficiency often differ among patients with gastrointestinal diseases or diabetes (type 1 and type 2), and among elderly subjects. Finally, although there is currently limited clinical evidence, numerous extrapancreatic diseases and conditions that are highly prevalent in the general population may also be considered potential targets for PERT and related treatments.

NANETS treatment guidelines: well-differentiated neuroendocrine tumors of the stomach and pancreas

Well-differentiated neuroendocrine tumors (NETs) of the stomach and pancreas represent 2 major subtypes of gastrointestinal NETs. Historically, there has been little consensus on the classification and management of patients with these tumor subtypes. We provide an overview of well-differentiated NETs of the stomach and pancreas and describe consensus guidelines for the treatment of patients with these malignancies.

Gastric acid hypersecretory states: recent insights and advances

Gastric acid hypersecretory states are characterized by basal hypersecretion of gastric acid and historically include disorders associated with hypergastrinemia, hyperhistaminemia, and those of unknown etiology. Although gastric acid secretion is infrequently measured, it is important to recognize the role of gastric hypersecretion in the symptoms of these disorders because they share several features of pathogenesis and treatment. In this article, recent important articles reporting insights into their diagnosis, pathogenesis, and treatment are reviewed. Particular attention is paid to Zollinger-Ellison syndrome, because it has the most extreme acid hypersecretion of this group of disorders and because numerous recent articles deal with various aspects of the diagnosis, molecular pathogenesis, and treatment of the gastrinoma itself or the acid hypersecretion. Two new hypersecretory disorders are reviewed: rebound acid hypersecretion after the use of proton pump inhibitors and acid hypersecretion with cysteamine treatment in children with cystinosis.

Effects of esomeprazole on acid output in patients with Zollinger-Ellison syndrome or idiopathic gastric acid hypersecretion

OBJECTIVES

To evaluate the efficacy and safety of oral esomeprazole in the control of gastric acid hypersecretion in patients with hypersecretory states.

METHODS

In this 12-month, open-label, multicenter study, acid output (AO) was evaluated at baseline, day 10, and months 3, 6, and 12. The starting dose of esomeprazole was 40 mg or 80 mg twice daily. On day 10, patients with controlled AO were maintained on the same dose, while those with uncontrolled AO had their doses increased (maximum dose 240 mg/day) until control was attained. Esophagogastroduodenoscopy (EGD) was performed at baseline and at 6 and 12 months. Safety and tolerability were assessed throughout the study by EGD, gastric analysis, and adverse events.

RESULTS

Twenty-one patients (19 with Zollinger-Ellison syndrome [ZES], 2 with idiopathic gastric acid hypersecretion [IGH]) completed the study. Of the 20 patients with controlled AO at day 10, 18 (90%) had sustained AO control for the rest of the study. At 12 months, AO was controlled in 14 of 16 patients receiving esomeprazole 40 mg twice daily, in all 4 patients receiving esomeprazole 80 mg twice daily, and in the 1 patient receiving esomeprazole 80 mg 3 times daily. At 6 and 12 months, no patient had endoscopic evidence of mucosal disease. Esomeprazole was well tolerated; 1 patient had a serious adverse event (hypomagnesemia) attributed to treatment that resolved with magnesium supplementation during continued treatment.

CONCLUSION

Esomeprazole in appropriately titrated doses controls AO over 12 months in patients with hypersecretory states and is well tolerated.