The cckOMA syndrome and its relation to the Zollinger-Ellison syndrome: a diagnostic challenge.

OBJECTIVE: Among patients with enteropancreatic neuroendocrine tumor syndromes only one case with a cholecystokinin (CCK) secreting tumor has been reported. She had significant hyperCCKemia leading to a specific syndrome of severe diarrheas, weight loss, repeated duodenal ulcers and a permanently contracted gallbladder with gallstones. There are, however, reasons to believe that further CCKomas exist, for instance among Zollinger-Ellison patients with normal plasma gastrin concentrations. The present review is a call to gastroenterologists for awareness of such CCKoma patients. METHOD: After a short case report, the normal endocrine and oncological biology of CCK is described. Subsequently, the CCKoma symptoms are discussed with particular reference to the partly overlapping symptoms of the Zollinger-Ellison syndrome. In this context, the diagnostic use of truly specific CCK and gastrin assays are emphasized. The discussion also entails the problem of access to accurate CCK measurements. CONCLUSION: Obviously, the clinical awareness about the CCKoma syndrome is limited. Moreover, it is also likely that the knowledge about the necessary specificity demands of diagnostic gastrin and CCK assays have obscured proper diagnosis of the CCKoma syndromes in man.

Multiple endocrine neoplasia type 1 with Zollinger-Ellison syndrome: clinicopathological analysis of a Japanese family with focus on menin immunohistochemistry.

Background: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the occurrence of multiple epithelial neuroendocrine tumors (NETs) and non-NETs in various organs. MEN1 encodes a 610-amino acid-long tumor suppressor protein, menin. The optimal treatment for multiple tumors, identification of the most critical tumors for patient prognosis, and menin immunohistochemistry findings remain controversial. Therefore, we aimed to elucidate these issues through a histological analysis of tumors and tumor-like lesions in a Japanese family, comprising a father and his two sons, who had MEN1 with Zollinger-Ellison syndrome (ZES). Patients and methods: All family members had a germline alteration in exon 10, c.1714-1715 del TC of MEN1, and exhibited multiple synchronous and metachronous tumors. The patients had pulmonary NETs, hyperparathyroidism, hypergastrinemia, pituitary adenomas, pancreaticoduodenal NETs, adrenocortical adenoma with myelolipoma, nodular goiter of the thyroid, lipomas, and angiofibroma. Most tumors were resected and histologically examined. We compared their clinical courses and tumor histology, and conducted menin immunohistochemistry (IHC). Results: Two patients died of pulmonary NET G2. One patient who underwent pancreaticoduodenectomy was cured of ZES; however, the two other patients who did not undergo pancreaticoduodenectomy suffered persistent ZES despite treatment with octreotide. Menin IHC revealed varying NET intensities, ranging from positive to negative stains. Conclusion: Pancreaticoduodenectomy is the most effective treatment for ZES. Long-term follow-up is essential for pulmonary NET G2 owing to the risk of distant metastasis and/or multiplicity. Moreover, the variability of menin IHC in MEN1-related tumors may indicate the pattern of tumor formation rather than the diagnostic utility of menin in MEN1.

All you need to know about gastrinoma today | Gastrinoma and Zollinger-Ellison syndrome: A thorough update.

Zollinger-Ellison syndrome (ZES) is a distinct syndrome characterized by hyperchlorhydria-induced peptic ulcer disease and chronic diarrhea. It is the result of a gastrin-excess state caused by a duodenal or pancreatic neuroendocrine tumor referred to as gastrinoma. This gastrin-secreting neuroendocrine tumor is usually sporadic in nature, or part of multiple endocrine neoplasia type 1 syndrome. The high rate of malignancy associated with gastrinomas substantiates the need for early diagnosis. In order to diagnose ZES with laboratory tests, patients under antacid medication are required to stay off proton pump inhibitors for at least one week and H2 receptor antagonists for 48 h. Fasting serum gastrin level measurement serves as an initial and fundamental diagnostic test, boasting a sensitivity of 99%. Gastrinoma patients will present with a gastrin level greater than 100 pg/mL, while a serum gastrin level higher than 1000 pg/mL, in the presence of gastric pH <2, is considered diagnostic. Since more common causes of hypergastrinemia exist in the setting of hypochlorhydria, ruling those out should precede ZES consideration. Such causes include atrophic gastritis, Helicobacter pylori (H. pylori)-associated pangastritis, renal failure, vagotomy, gastric outlet obstruction and retained antrum syndrome. The secretin stimulation test and the calcium gluconate injection test represent classic adjuvant diagnostic techniques, while alternative approaches are currently being introduced and evaluated. Specifically, the secretin stimulation test aids in differentiating ZES cases from other hypergastrinemic states. Its principle is based on secretin stimulation of gastrinoma cells to secrete gastrin, while inhibiting normal G cells. The rapid intravenous infusion of 4 µg/kg secretin over 1 min is followed by gastrin level evaluation at specific intervals post-infusion. Localization of the primary tumor and its metastases is the next diagnostic step when gastrinoma-associated ZES is either suspected or biochemically confirmed. Endoscopic ultrasound has showcased sensitivity as high as 83% for pancreatic gastrinomas and is considered the primary modality in such cases, although its tumor detection rates are substantially lower in duodenal lesions. Gallium-68 radiotracers, especially DOTATOC with positron emission tomography, are currently setting the standard in tumor localization, enhancing traditional imaging techniques and showcasing high sensitivity and specificity. Although gastrinomas have been reported in various anatomic locations, the vast majority arise in a specific site named the "gastrinoma triangle", involving parts of the duodenum, pancreas and extra-hepatic biliary system. Proton pump inhibitors serve as the cornerstone of symptomatic ZES treatment. Surgery is routinely performed in localized sporadic ZES, irrespective of imaging results. ZES in multiple endocrine neoplasia type 1 requires work-up for evaluation and treatment of hyperparathyroidism, while surgery might be an option for selected cases. In cases of advanced and metastatic disease, there is a variety of potential treatments, ranging for somatostatin analogs to chemotherapeutic drugs, liver-directed therapies and liver transplantation, while neither hepatic metastases, nor locally invasive disease necessarily preclude surgical management. This article thoroughly and critically reviews available literature and provides an extensive and multidimensional overview of ZES, along with current controversies regarding management of this disease.

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.

[Primary lymph node gastrinoma]. / Gastrinoma primario de ganglio linfático.

Gastrinomas are neuroendocrine tumors usually located in the duodenum and pancreas, in the context of a Multiple Endocrine Neoplasm and forming a Zollinger-Ellison syndrome. The location of this type of lymph node tumor is extremely unusual and its early diagnosis constitutes a real challenge to be able to establish an adequate treatment and manage the complications that these entail. We present the case of a 64-year-old male patient with a lymph node gastrinoma and whose surgical removal resulted in the immediate remission of the patient's symptoms.

Neurofibromatosis Type 1: A Rare Predisposition for Gastrinomas and Other Neuroendocrine Tumors.

ABSTRACT: Neurofibromatosis type (NF-1) is an autosomal dominant disorder characterized predominantly by neurocutaneous manifestations. Involvement of the gastrointestinal tract is uncommon but is associated with a significant risk of malignancy. There are a handful of case reports linking NF-1 with pancreatic neuroendocrine tumors; these include gastrin-secreting variants with the attendant Zollinger-Ellison syndrome. We present the case of a 52-year-old lady who presented with recurrent peptic ulceration and diarrhea. Serum gastrin levels were elevated and magnetic resonance imaging demonstrated the presence of a pancreatic lesion with multiple liver metastases. The lesion was moderately fludeoxyglucose avid on positron emission tomography-computed tomography. Endoscopic ultrasonography-guided sampling revealed the presence of synaptophysin positive neuroendocrine cells with positive gastrin immunostaining. A conservative approach was adopted, and the patient's symptoms improved on proton pump inhibitors. Zollinger-Ellison syndrome is an important condition, which should be kept in mind in the patient with NF-1 who presents with recurrent peptic ulceration and diarrhea. The emerging association between these 2 conditions is being examined on a cellular and immunohistochemical level.

Secretin Stimulation Test and Early Diagnosis of Gastrinoma in MEN1 Syndrome: Survey on the MEN1 Florentine Database.

CONTEXT: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited endocrine cancer syndrome. Multiple gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) affect 30% to 80% of MEN1 patients, with the most common functioning GEP-NET being gastrinoma. Biochemical identification of hypergastrinemia may help to recognize the presence of gastrinomas before they are detectable by instrumental screening, enabling early diagnosis and start of therapy, preferably before tumor progression and metastases occurrence. OBJECTIVE: Evaluate the effectiveness of secretin stimulation test to precociously diagnose the presence of gastrin-secreting tumors. DESIGN: Results of secretin stimulation tests, performed between 1991 and February 2020, were retrospectively analyzed, as aggregate, in a cohort of MEN1 patients with GEP-NETs. SETTING: Data were extracted from the MEN1 Florentine database. PATIENTS: The study included 72 MEN1 patients with GEP-NETs who underwent a secretin stimulation test for the evaluation of gastrin secretion. OUTCOMES: A positive secretin stimulation test was assumed with a difference between basal fasting serum gastrin (FSG) and the maximum stimulated value of gastrin over 120 pg/mL. RESULTS: The secretin stimulation test showed a secretin-induced hypergastrinemia in 27.8% (20/72) of patients with GEP-NETs, and a positive test in 18 cases. The test allowed the identification of a positively stimulated hypergastrinemia in 75.0% (3/4) of patients who presented a basal FSG within the normal range. CONCLUSIONS: Diagnosis of gastrinoma is complex, difficult, and controversial. Results of this study confirm that a positive secretin stimulation test allows early diagnosis of gastrinomas, even in the presence of borderline or normal levels of nonstimulated FSG.

Gastrinoma and Zollinger Ellison syndrome: A roadmap for the management between new and old therapies.

Zollinger-Ellison syndrome (ZES) associated with pancreatic or duodenal gastrinoma is characterized by gastric acid hypersecretion, which typically leads to gastroesophageal reflux disease, recurrent peptic ulcers, and chronic diarrhea. As symptoms of ZES are nonspecific and overlap with other gastrointestinal disorders, the diagnosis is often delayed with an average time between the onset of symptoms and final diagnosis longer than 5 years. The critical step for the diagnosis of ZES is represented by the initial clinical suspicion. Hypergastrinemia is the hallmark of ZES; however, hypergastrinemia might recognize several causes, which should be ruled out in order to make a final diagnosis. Gastrin levels > 1000 pg/mL and a gastric pH below 2 are considered to be diagnostic for gastrinoma; some specific tests, including esophageal pH-recording and secretin test, might be useful in selected cases, although they are not widely available. Endoscopic ultrasound is very useful for the diagnosis and the local staging of the primary tumor in patients with ZES, particularly in the setting of multiple endocrine neoplasia type 1. Some controversies about the management of these tumors also exist. For the localized stage, the combination of proton pump inhibitory therapy, which usually resolves symptoms, and surgery, whenever feasible, with curative intent represents the hallmark of gastrinoma treatment. The high expression of somatostatin receptors in gastrinomas makes them highly responsive to somatostatin analogs, supporting their use as anti-proliferative agents in patients not amenable to surgical cure. Other medical options for advanced disease are super-imposable to other neuroendocrine neoplasms, and studies specifically focused on gastrinomas only are scant and often limited to case reports or small retrospective series. The multidisciplinary approach remains the cornerstone for the proper management of this composite disease. Herein, we reviewed available literature about gastrinoma-associated ZES with a specific focus on differential diagnosis, providing potential diagnostic and therapeutic algorithms.

Validity of Secretin Stimulation Testing on Proton Pump Inhibitor Therapy for Diagnosis of Zollinger-Ellison Syndrome.

INTRODUCTION: Zollinger-Ellison syndrome (ZES) is characterized by gastrinoma-induced hypergastrinemia causing excessive gastric acid secretion. Secretin stimulation tests (SSTs) are required for diagnosis in the majority of patients. Two case reports suggest that proton pump inhibitors (PPIs) cause false SST results. Consequently, PPIs are discontinued to allow hyperchlorhydria to recur; however, uncontrolled acidity can cause life-threatening complications in those with underlying undiagnosed ZES. The aim of this study was to determine whether PPIs influence the validity of SSTs for the diagnosis of ZES. METHODS: A retrospective chart review was performed. Charts of patients who underwent SSTs were reviewed to determine whether they were performed on or off PPI and the test's accuracy by comparing the results with gold standard tests (diagnostic laboratory testing performed off PPI or surgical pathology consistent with gastrinoma). Sensitivity, specificity, and positive predictive value (PPV) of SST on PPI were calculated and results compared with SST off PPI using noninferiority analyses. RESULTS: Twenty-eight patients corresponding to 29 SSTs were performed on PPI, and 70 patients corresponding to 107 SSTs were performed off PPI. Most of them were female and white and had multiple endocrine neoplasia type 1. We found no false-positive or false-negative SSTs on PPI. Sensitivity, specificity, and PPV of SSTs on PPI were determined to be noninferior to SSTs off PPI (P ≤ 0.05 for all). DISCUSSION: In our cohort, SSTs on PPI compared with SSTs off PPI were noninferior for sensitivity, specificity, and PPV. These results suggest that PPI withdrawal before SSTs may not be necessary.

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.

[Neuroendocrine neoplasia of the stomach : What is new?] / Neuroendokrine Neoplasien des Magens : Was ist neu?

INTRODUCTION: Neuroendocrine Neoplasms are classified according to the new WHO classification in (1.) well differentiated neuroendocrine tumors G1 (NET G1, Ki67 ≤ 2 or mitosis count <2) and (2.) well differentiated neuroendocrine tumors G2 (NET G2, Ki67 3-20 or mitosis count 2-20) and (3.) poorly differentiated neuroendocrine carcinomas G3 (NEC G3, Ki67 > 20 or mitosis count >20). MATERIAL AND METHODS: In this study 310 NENs of the Ludwig-Maximilians-University in Munich were reevaluated according to the new WHO classification. RESULTS: 7% of the analyzed NENs were presented as neoplasias of the stomach. In NENs of the stomach three distinct subtypes are recognized: (1) type 1 associated with autoimmune chronic atrophic gastritis (2) type 2, associated with multiple endocrine neoplasia (MEN1) and Zollinger-Ellison Syndrom; and (3) type 3, sporadic tumors. DISCUSSION: Precursor lesions (i. e. hyperplasia of the ECL cells) are found in patients with hypergastrinaemia (type 1 and 2). This article should provide insights into the diagnosis of NENs of the stomach with emphasis on the new international standard.