Sporadic and MEN1-related gastrinoma and Zollinger-Ellison syndrome: differences in clinical characteristics and survival outcomes.

PURPOSE: Gastrinoma with Zollinger-Ellison syndrome (ZES) may occur sporadically (Sp) or as part of the inherited syndrome of multiple endocrine neoplasia 1 (MEN-1). Data comparing Sp and MEN-1/ZES are scanty. We aimed to identify and compare their clinical features. METHODS: Consecutive patients with ZES were evaluated between 1992 and 2020 among a monocentric Italian patient cohort. RESULTS: Of 76 MEN-1 patients, 41 had gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN), 18 of whom had ZES; of 320 Sp-GEP-NEN, 19 had Sp-ZES. MEN-1/ZES patients were younger (p = 0.035) and the primary MEN-1/ZES gastrinoma was smaller than Sp-ZES (p = 0.030). Liver metastases occurred in both groups, but only Sp-ZES developed extrahepatic metastases. 13 Sp-ZES and 8 MEN-1/ZES underwent surgery. 8 Sp-ZES and 7 MEN-1/ZES received somatostatin analogs (SSAs). Median overall survival (OS) was higher in MEN-1/ZES than in Sp-ZES (310 vs 168 months, p = 0.034). At univariate-logistic regression, age at diagnosis (p = 0.01, OR = 1.1), G3 grading (p = 0.003, OR = 21.3), Sp-ZES (p = 0.02, OR = 0.3) and presence of extrahepatic metastases (p = 0.001, OR = 7.2) showed a significant association with OS. At multivariate-COX-analysis, none of the variables resulted significantly related to OS. At univariate-logistic regression, age (p = 0.04, OR = 1.0), size (p = 0.039, OR = 1.0), G3 grade (p = 0.008, OR = 14.6) and extrahepatic metastases (p = 0.005, OR = 4.6) were independently associated with progression-free survival (PFS). In multivariate-COX-analysis, only extrahepatic metastases (p = 0.05, OR = 3.4) showed a significant association with PFS. Among SSAs-treated patients, MEN-1/ZES showed better PFS (p = 0.0227). After surgery, the median PFS was 126 and 96 months in MEN-1 and Sp, respectively. CONCLUSION: MEN-1/ZES patients generally show better OS and PFS than Sp-ZES as well as better SSAs response.

Somatostatin analogs in patients with Zollinger Ellison syndrome (ZES): an observational study.

PURPOSE: Zollinger Ellison syndrome (ZES) is a rare syndrome caused by gastrin hypersecretion from a gastrinoma. Gastrinoma treatment has two goals: the control of acid hypersecretion and the control of tumor growth. While therapy for the syndrome is univocally based on proton pump inhibitors, the one for disease control is still debated. We here aimed at evaluating the role of somatostatin analogs (SSAs) in the control of tumor progression in a series of ZES patients. METHODS: A retrospective analysis of a prospectively collected database of ZES patients, followed and managed from 1990 to 2019, was performed. The patients' clinical, pathological, treatment, and follow-up data were analyzed. Data regarding SSAs therapy start, dosage, duration, and side effects were collected. RESULTS: 33 patients with ZES were diagnosed. Fourteen patients (42%) had a grade 1 (G1) neuroendocrine neoplasm (NEN), five had G2 (15%), none had G3. Fifteen patients (45%) had metastatic disease. Overall, 12 (36%) underwent SSAs therapy. The median treatment duration was 36 months. Eight patients (67%) had a sustained response to SSAs, four (33%) showed an early progression, with a significant difference in terms of PFS between the patients with early and late progression (84 vs 2 months, p = 0.004). No differences in terms of OS and PFS were observed between the treated and non-treated patients, despite the proportion of metastatic patients was greater in the SSAs-treated group (75% vs 29% in the non-treated group, p = 0.01). CONCLUSION: Present data support the use of SSAs in ZES, considering that gastrinoma is mainly a well-differentiated low-grade tumor (G1 or G2), with a high expression of somatostatin receptors.

Proton Pump Inhibitor Use, Hypergastrinemia, and Gastric Carcinoids-What Is the Relationship?

Neuroendocrine tumors (NETs) throughout the body are the focus of much current interest. Most occur in the gastrointestinal tract and have shown a major increase in incidence over the past 30 years, roughly paralleling the world-wide increase in the use of proton pump inhibitor (PPI) drugs. The greatest rise has occurred in gastric carcinoids (g-NETs) arising from enterochromaffin-like (ECL) cells. These tumors are long known to occur in auto-immune chronic atrophic gastritis (CAG) and Zollinger-Ellison syndrome (ZES), with or without multiple endocrine neoplasia type-1 (MEN-1), but the incidences of these conditions do not appear to have increased over the same time period. Common to these disease states is persistent hypergastrinemia, generally accepted as causing g-NETs in CAG and ZES, and postulated as having similar tumorigenic effects in PPI users. In efforts to study the increase in their occurrence, g-NETs have been classified in a number of discussed ways into different grades that differ in their incidence and apparent pathogenesis. Based on a large amount of experimental data, tumorigenesis is mediated by gastrin's effects on the CCK2R-receptor on ECL-cells that in turn leads to hyperplasia, dysplasia, and finally neoplasia. However, in all three conditions, the extent of response of ECL-cells to gastrin is modified by a number of genetic influences and other underlying risk factors, and by the duration of exposure to the hormonal influence. Data relating to trophic effects of hypergastrinemia due to PPI use in humans are reviewed and, in an attached Appendix A, all 11 reports of g-NETs that occurred in long-term PPI users in the absence of CAG or ZES are summarized. Mention of additional suspected cases reported elsewhere are also listed. Furthermore, the risk in humans may be affected by the presence of underlying conditions or genetic factors, including their PPI-metabolizer phenotype, with slow metabolizers likely at increased risk. Other problems in estimating the true incidence of g-NETs are discussed, relating to non-reporting of small tumors and failure of the Surveillance, Epidemiology, and End Results Program (SEER) and other databases, to capture small tumors or those not accorded a T1 rating. Overall, it appears likely that the true incidence of g-NETs may be seriously underestimated: the possibility that hypergastrinemia also affects tumorigenesis in additional gastrointestinal sites or in tumors in other organ systems is briefly examined. Overall, the risk of developing a g-NET appears greatest in patients who are more than 10 years on drug and on higher doses: those affected by chronic H. pylori gastritis and/or consequent gastric atrophy may also be at increased risk. While the overall risk of g-NETs induced by PPI therapy is undoubtedly low, it is real: this necessitates caution in using PPI therapy for long periods of time, particularly when initiated in young subjects.

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.

Gastrinoma and Zollinger-Ellison syndrome in canids: a literature review and a case in a Mexican gray wolf.

Gastrinoma, an infrequent diagnosis in middle-aged dogs, occurs with nonspecific gastrointestinal morbidity. Laboratory tests can yield a presumptive diagnosis, but definitive diagnosis depends on histopathology and immunohistochemistry. We describe a malignant pancreatic gastrinoma with lymph node metastases and corresponding Zollinger-Ellison syndrome in a Mexican gray wolf ( Canis lupus baileyi) and review this endocrine neoplasm in domestic dogs. A 12-y-old, captive, male Mexican gray wolf developed inappetence and weight loss. Abdominal ultrasonography revealed a thickened duodenum and peritoneal effusion. Two duodenal perforations were noted on exploratory celiotomy and were repaired. Persisting clinical signs led to a second celiotomy that revealed a mesenteric mass, which was diagnosed histologically as a neuroendocrine carcinoma. During the following 16 mo, the wolf received a combination of H2-receptor antagonists, proton-pump inhibitors, gastroprotectants, and anti-emetics, but had recurrent episodes of anorexia, nausea, acid reflux, and remained underweight. Worsening clinical signs and weakness prompted euthanasia. The antemortem serum gastrin concentration of 414 ng/L (reference interval: 10-40 ng/L) corroborated hypergastrinemia. Autopsy revealed a mass expanding the right pancreatic limb; 3 parapancreatic mesenteric masses; duodenal ulcers; focal duodenal perforation with septic fibrinosuppurative peritonitis; chronic-active ulcerative esophagitis; and poor body condition. The pancreatic mass was diagnosed histologically as a neuroendocrine carcinoma and the parapancreatic masses as lymph node metastases. Immunohistochemistry of the pancreatic mass was positive for gastrin and negative for glucagon, insulin, pancreatic polypeptide, serotonin, somatostatin, and vasoactive intestinal peptide.

Diagnosis and management of Zollinger-Ellison syndrome in 2018.

Zollinger-Ellison syndrome (ZES) is a clinical syndrome characterized by gastric acid hypersecretion due to the ectopic secretion of gastrin by a gastrinoma, a neuroendocrine tumor (NET) which mostly develops in the duodenum and in the pancreas. This syndrome was first described by Zollinger and Ellison in 1964; if left untreated, ZES can lead to multiple complications mainly due to gastric hypersecretion and some patients can suffer from the complications of an advanced metastatic disease. Although its clinical features are considered typical, the diagnosis of ZES is often challenging for the clinician. A previous review was published in 2005 by our group, but in 12 years many things have changed: the diagnostic tools have been improved and many different therapeutical options are now available.

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.

The appropriate use of proton pump inhibitors (PPIs): Need for a reappraisal.

The advent of powerful acid-suppressive drugs, such as proton pump inhibitors (PPIs), has revolutionized the management of acid-related diseases and has minimized the role of surgery. The major and universally recognized indications for their use are represented by treatment of gastro-esophageal reflux disease, eradication of Helicobacter pylori infection in combination with antibiotics, therapy of H. pylori-negative peptic ulcers, healing and prophylaxis of non-steroidal anti-inflammatory drug-associated gastric ulcers and control of several acid hypersecretory conditions. However, in the last decade, we have witnessed an almost continuous growth of their use and this phenomenon cannot be only explained by the simple substitution of the previous H2-receptor antagonists, but also by an inappropriate prescription of these drugs. This endless increase of PPI utilization has created an important problem for many regulatory authorities in terms of increased costs and greater potential risk of adverse events. The main reasons for this overuse of PPIs are the prevention of gastro-duodenal ulcers in low-risk patients or the stress ulcer prophylaxis in non-intensive care units, steroid therapy alone, anticoagulant treatment without risk factors for gastro-duodenal injury, the overtreatment of functional dyspepsia and a wrong diagnosis of acid-related disorder. The cost for this inappropriate use of PPIs has become alarming and requires to be controlled. We believe that gastroenterologists together with the scientific societies and the regulatory authorities should plan educational initiatives to guide both primary care physicians and specialists to the correct use of PPIs in their daily clinical practice, according to the worldwide published guidelines.

[Switching to a generic drugA blessing or a curse?]. / Overstappen op een generiek geneesmiddel.

A patient suffering from Zollinger-Ellison was treated with Nexium, but after patent expiry only the costs of generic omeprazol were reimbursed. Generic tablets and capsules, pantoprazol and rabeprazol, were tried without success and finally the pharmacist dispensed Nexium at his own expense. Registered generic drugs have been shown to be bioequivalent with the originator drug within narrow margins. When two batches of the originator are compared, the same requirements are valid. Although the subject has received a lot of negative publicity, meta-analyses on outcome comparison support generic substitution; problems associated with switching can be partially explained by the loss of trust in the treatment, and differences in appearance also cause confusion. Generic prescribing should be encouraged to keep medical treatment affordable; however, in order to prevent the problems described it is desirable to keep to the same product as far as possible. Effective education and patient information are essential if switching is to be successful.

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.

Severe symptomatic hypomagnesaemia induced by the chronic use of proton pump inhibitors: a case report of a patient with Zollinger-Ellison syndrome.

The association between proton pump inhibitor (PPI) therapy and hypomagnesaemia has been recognized since 2006. We report the case of a 51-year-old woman who developed severe symptomatic hypomagnesaemia after a long-term PPI therapy given for recurrent peptic ulcer disease. Hypomagnesaemia could only partially be resolved during substitution therapy, but was corrected after withdrawal of the PPI. Recurrence of hypomagnesaemia occurred after retreatment with PPIs, supporting the causal relationship. An underlying gastric acid hypersecretion (Zollinger-Ellison syndrome) was highly suspected and eventually controlled by a combination of a histamine 2-receptor antagonist and octreotide, without the need for further PPI therapy after 2 years of follow-up.

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.

[PPI-sensitive diarrhea - unusual case of an adolescent with sporadic gastrinoma]. / Ansprechen einer episodenhaften chronischen Diarrhoe auf Protonenpumpenhemmer. Seltener Fall eines Jugendlichen mit sporadischem Gastrinom.

HISTORY AND CLINICAL FINDINGS: A 14-year-old boy was admitted to hospital because of chronic episodic diarrhea lasting for 4 years. Previous investigations in the past had not revealed the cause of the symptoms. INVESTIGATIONS: The 13C-triglyceride breathing test showed a diminished intestinal lipolysis. Endoscopic examination demonstrated small gastroduodenic ulcers. During therapy with proton-pump inhibitors the diarrhea stopped. DIAGNOSIS, TREATMENT AND COURSE: The combination of gastroduodenic ulcers and improvement of diarrhea with PPI-therapy were suggestive of Zollinger-Ellison syndrome. Endosonography and MR-scan showed an extrapancreatic mass with marked activity during somatostatin receptor scintigraphy. The primary tumor was excised, a liver metastasis was treated with radiofrequency ablation. The histological examination confirmed the diagnosis of a gastrinoma. CONCLUSION: In patients with chronic diarrhea, especially if the symptoms are PPI-sensitive, a gastrinoma should be considered.

Rabeprazole for the treatment of acid-related disorders.

Proton pump inhibitors are widely used for the treatment of acid-related disorders. Rabeprazole is a potent and irreversible inhibitor of H(+)/K(+)-ATPase gastric pump, and it is indicated for the treatment of gastroesophageal reflux disease, Zollinger Ellison syndrome, duodenal and gastric ulcers and for the eradication of Helicobacter pylori in combination with antibiotics. Pharmacokinetic and pharmacodynamic data show that rabeprazole achieves a pronounced acid suppression from the first administration that is maintained with repeated use; this may translate into faster onset of symptom relief for patients, particularly suitable when the indication is for the on-demand long-term maintenance of gastroesophageal reflux disease. Due to its predominantly nonenzymatic metabolism, rabeprazole has a lower potential for drug-drug interactions. The objective of this article is to update efficacy and safety data of rabeprazole in the treatment of acid-related disorders, following a previous review dated 2008.

The Zollinger-Ellison syndrome: dangers and consequences of interrupting antisecretory treatment.

BACKGROUND & AIMS: Patients with Zollinger-Ellison syndrome (ZES) are treated by proton pump inhibitors (PPIs) to protect them from severe and potentially lethal peptic complications related to massive gastric acid hypersecretion. We report here on the dangerous consequences of interrupting PPI therapy. METHODS: We describe 2 ZES patients in whom interruption of PPI treatment for diagnostic evaluation generated severe health complications. RESULTS: Less than 48 hours after stopping PPIs, patient 1 developed multiple strictures of the esophagus caused by massive vomiting of gastric acid, and patient 2 presented with severe abdominal pain with intestinal microperforation from duodenal ulcers. Because of persistent gastrin stimulatory drive and because of the abolition of reflex protective defense mechanisms against gastric acid hypersecretion during PPI treatment, patients with ZES under PPI therapy are exposed to severe peptic complications when facing rebound acid secretion at the interruption of their antisecretory treatment. CONCLUSIONS: PPI treatment interruption has dangerous consequences, and PPI therapy always should be maintained in patients known or suspected of ZES. Diagnostic evaluations should be performed under PPI protection.

Zollinger-Ellison syndrome: presentation, response to therapy, and outcome.

BACKGROUND: Recent series describing the clinical presentation, response to therapy, and long-term outcome of Zollinger-Ellison syndrome are limited. AIMS: To assess the clinical characteristics and long-term outcome of patients with Zollinger-Ellison syndrome. METHODS: Over a 20-year period, patients with Zollinger-Ellison syndrome were enrolled in a prospective trial evaluating the efficacy of lansoprazole. Following dose stabilization, patients were followed on a 6-monthly basis with interval history, physical examination, endoscopy with gastric biopsies, gastric acid analysis and laboratory studies. RESULTS: 72 patients (mean age 54±12 years, % male 58%, % Caucasian 69%) were prospectively enrolled. The clinical presentation was stereotypical for Zollinger-Ellison syndrome. Symptoms had been reported for a median of 9 years prior to diagnosis. Cross-sectional abdominal imaging was often negative for demonstrable tumour. All patients had gastric acid hypersecretion controlled with variable doses of lansoprazole (median dose 60 mg/day, range 15-480 mg/day). The median survival from the time of diagnosis was 6.6 years; only two of 19 deaths were due to metastatic gastrinoma. CONCLUSIONS: The clinical presentation of Zollinger-Ellison syndrome was similar to prior reports. Acid hypersecretion was controlled in all patients with variable doses of lansoprazole. Long-term survival was principally related to underlying co-morbidity.

CYP2C19-guided design of a proton pump inhibitor dose regimen to avoid the need for pharmacogenetic individualization in H. pylori eradication.

OBJECTIVE: It has been demonstrated that genetic variation in CYP2C19 has a significant influence upon H. pylori eradication rates. We have determined a dosage regimen of lansoprazole that will provide EMs with exposure approximately equivalent to that obtained by PMs treated with standard doses and determined the exposure that a PM would experience if they were to be treated with this 'EM optimised' lansoprazole dose. METHODS: Non-compartmental pharmacokinetic parameters (AUC, C(max), t(max)) for CYP2C19 genotypes were obtained from the literature. Primary pharmacokinetic parameters (CL, Vd, ka) for 200 virtual patients were calculated from the weighted non-compartmental variables and used to simulate a 7 day treatment course of twice daily lansoprazole, at standard and optimised doses for 1,000 patients. RESULTS: The administration of 180 mg twice daily to CYP2C19 EMs results in approximately equivalent exposure to lansoprazole as the administration of standard 30 mg twice daily doses to PMs. Administration of this six-fold dose increase to EMs is predicted to result in only a 2.5-fold increase in C(max) when compared with PMs receiving the standard 30 mg dose. CONCLUSION: We present a potential lansoprazole dosing regimen that should result in improved H. pylori eradication within CYP2C19 EMs and may not require individualization. Whilst the optimised dose represents a significant increase, it is below that reported in the chronic management of Zollinger-Ellison syndrome. On the basis that treatment is of limited duration and lansoprazole is generally well tolerated, such an approach warrants further in vivo evaluation to confirm drug exposure, efficacy and tolerability.