[Evolution of clinical ideas about Zollinger-Ellison syndrome].

The paper gives the current views of the diagnosis and treatment of Zollinger-Ellison syndrome (ZES). It underlines the importance of including ZES in differential diagnosis in patient with frequently recurrent and standard-dose proton pump inhibitor therapy-resistant erosive and ulcerative lesions of the upper gastrointestinal tract. It provides the current stepwise algorithm for the diagnosis of the pathology in question. Relevant and promising treatments in patients with ZES are considered.

Mechanism of acid hypersecretion post curative gastrinoma resection.

BACKGROUND: Some patients with Zollinger-Ellison syndrome post curative gastrinoma resection continue to show gastric acid hypersecretion; however, the mechanism is unknown. AIM: The aim of this study was to prospectively study acid secretion following curative gastrinoma resection and analyze factors contributing in patients with Zollinger-Ellison syndrome. METHODS: Fifty patients cured post gastrinoma resection were studied with serial assessments of acid secretory status, cure status and ECL-cell status/activity (with serial biopsies, CgA, urinary N-MIAA). Correlative analysis was performed to determine predictive factors. RESULTS: Hypersecretion occurred in 31 patients (62%) and 14 had extreme-hypersecretion. There was an initial decline (3-6 months) in BAO/MAO, which then remained stable for eight years. Preoperative BAO correlated with the postoperative secretion, but not other clinical, tumoral, laboratory variables, the degree of postoperative acid suppression or type of antisecretory drug needed. Hypersecretors had greater postoperative ECL changes (P=0.005), serum CGA (P=0.009) and 24-h urinary N-MIAA (P=0.0038). CONCLUSIONS: Post curative resection, gastric hypersecretion persists long term (mean 8 years) in 62% of patients and in 28% it is extreme, despite normogastrinemia. No preoperative variable except BAO correlates with postresection hypersecretion. The persistent increased ECL-cell extent post curative resection suggests prolonged hypergastrinemia can lead to changes in ECL-cells that are either irreversible in humans or sustained by unknown mechanisms not involving fasting hypergastrinemia and which can result in hypersecretion, in a proportion of which it can be extreme. Whether similar findings may occur in patients with idiopathic GERD treated for prolonged periods (>10 years) with PPIs, at present, is unknown.

Costs and risks in the management of patients with gastric acid hypersecretion.

GOALS: To define both risks and costs of optimal care of patients with gastric acid hypersecretion. BACKGROUND: The management of Zollinger-Ellison syndrome and other gastric acid hypersecretory disorders remains challenging. The optimal strategy for follow-up including gastric acid analysis, laboratory studies, and endoscopy is unknown but important given the potential complications from uncontrolled acid secretion. STUDY: Over the last 18 years, patients with gastric acid hypersecretory disorders have been followed prospectively with gastric acid analysis and endoscopy titrating oral lansoprazole and evaluating for complications. Protocol driven charges were calculated using the most recent information available. RESULTS: After 1 year of treatment optimization, 19 of 67 patients had 43 relapses, (once only in 10 patients). Risk markers for relapse included: (1) antrectomy, 67% relapsed versus 21% in unoperated patients; (2) basal acid output >5 mmol/h (risk=5.17); and (3) poor compliance. On treatment, 79% of 58 intact patients (excluding antrectomy) were lesion-free; 11% had only 1 relapse. Thus 90% were well managed with optimized lansoprazole alone. Protocol driven charges exceeded $25,000 the first year and $7000 annually thereafter. CONCLUSIONS: Relapse is infrequent and generally mild with acid secreting status closely monitored. The ideal strategy to balance costs and testing awaits further study.

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.

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.

Gastric emptying and secretion in Zollinger-Ellison syndrome.

Gastric emptying and secretion, as well as intragastric volume and composition, were determined simultaneously in three patients with Zollinger-Ellison syndrome and in seven normal subjects. Gastric hypersecretion was observed in patients with Zollinger-Ellison syndrome and in normal subjects receiving pentagastrin. In contrast, the fraction of gastric contents emptied per minute (fractional rate of emptying) was increased in Zollinger-Ellison patients and unchanged or decreased in normal subjects receiving pentagastrin. The increased fractional rate of gastric emptying in patients with Zollinger-Ellison syndrome persisted despite abolition of gastric hypersecretion by metiamide. Thus, the increased fractional gastric emptying seen in patients with Zollinger-Ellison syndrome is not attributable to hypergastrinemia, or to gastric hypersecretion per se. Instead, it appears to be caused by an undefined nervous or humoral factor.

Zollinger-Ellison syndrome in 2006: concepts from a clinical point of view.

Zollinger-Ellison syndrome (ZES) is characterised by peptic ulcers of the upper gastrointestinal tract failing to heal despite maximal medical therapy, diarrhoea and marked gastric acid hypersecretion associated with a gastrin-secreting tumour (gastrinoma). ZES might be associated with multiple endocrine neoplasia type 1. The main diagnostic features are hypergastrinemia and acid hypersecretion. When these parameters give borderline results, provocation test (with secretin or calcium) may be required. To identify the localisation of gastrinoma several imaging techniques have been proposed. Somatostatin receptor scintigraphy is capable to localise the tumour in 80% of the cases and to identify it even in anatomic sites other than pancreas and duodenum. Endoscopic ultrasonography has a sensitivity as high as 79-93% and a specificity of 93%. The 2 main principal therapeutic strategies are to control both the gastric acid hypersecretion and the growth of the neoplasia. Proton pump inhibitors (PPIs) are the drugs of choice for patients with ZES. Furthermore, safety of PPIs in the maintenance therapy has been proven both in short- and in long-term studies. The best surgical treatment is excision of gastrinoma before metastatic spread has occurred. Somatostatin-analogues can reduce both gastric acid hypersecretion and serum gastrin levels. Moreover, they have an antiproliferative effect. Chemotherapy, interferon and embolisation are indicated in rapidly evolving tumours or in cases in which the tumoral symptoms cannot be treated by other approaches.

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.

Gastric secretion in Zollinger-Ellison syndrome. Correlation with clinical expression, tumor extent and role in diagnosis--a prospective NIH study of 235 patients and a review of 984 cases in the literature.

We prospectively studied 235 patients with Zollinger-Ellison syndrome (ZES) (205 without and 30 with prior acid-reducing surgery) and compared the results with 984 patients from 182 reports in the literature. The aims of the study were to evaluate the sensitivity of proposed acid secretory criteria for the diagnosis of ZES, propose new criteria, evaluate the variability and methodology of gastric secretory testing, and correlate the symptoms and signs of ZES, tumor extent, and primary tumor size and location with the degree of gastric acid hypersecretion. Multiple endocrine neoplasia-type 1 (MEN1) occurred in 22% of patients. The mean basal acid output (BAO) in patients without and with prior acid-reducing surgery was 41.2 +/- 1.7 mEq/hr (range, 1.6-118.3 mEq/hr) and 27.6 +/- 3.5 mEq/hr (range 5.9-102.9 mEq/hr), respectively. In patients with MEN1, those with female gender, Hispanic, or Asian race had lower BAOs. Diarrhea, esophageal stricture, and pyloric scarring were associated with a higher BAO. Neither other symptoms nor the tumor extent, primary tumor location, or size correlated with the magnitude of acid hypersecretion. ZES diagnosis was delayed a mean of 5.5 +/- 0.4 yr. Patients who were misdiagnosed as having either Crohn or celiac disease had higher BAOs. The sensitivities from our study and the literature review of the proposed BAO criteria for the diagnosis of ZES in patients without previous gastric acid-reducing surgery were 91% and 90% for BAO > or = 15 mEq/hr, 86% and 82% for BAO > or = 18 mEq/hr, 69% and 67% for BAO > 25 mEq/hr, and < 60% for BAO > 31 mEq/hr, respectively. The specificities of all the proposed BAO criteria were high. Both the criterion of BAO > or = 15 mEq/hr and BAO > or = 18 mEq/hr had good specificities and equal sensitivity. With prior acid-reducing surgery, the sensitivities in our study and from the literature review were 100% and 81% for BAO > or = 5 mEq/hr, 73% and 45% for BAO > 14.4 mEq/hr, and 37% and 31% for BAO > 19.2 mEq/hr, respectively. The reported mean specificity for the criterion of BAO > or = 5 mEq/hr was 85%, while it was 100% for the other 2 criteria. The maximal acid output (MAO) criterion of > 70 mEq/hr had sensitivities in the present National Institutes of Health (NIH) study and the literature review of 39% and 31%, respectively, and the criterion of MAO > 100 mEq/hr had a sensitivity of < 15% in patients with no prior acid-reducing surgery. The proposed criterion of BAO/MAO ratio > 0.6 had a low sensitivity. The proposed criterion of the ratio of basal and maximal acid H+ concentration (BAC/MAC ratio) > or = 0.6 had an excellent sensitivity-- > or = 89% in patients with or without previous acid-reducing surgery. The reported specificity for both the BAO/MAO criterion and the BAC/MAC criterion were similar, but BAC/MAC had a better sensitivity. Combination criteria of BAO generally did not improve sensitivity. The criterion of pH < or = 1 was met by only 27% of patients, and pH < or = 0.96 by 21% of patients with previous acid-reducing surgery. For patients with MEN1 with no prior acid-reducing surgery, the sensitivities were lower compared with patients with the sporadic form of ZES. The mean gastric volume in patients without prior acid-reducing surgery was 314 +/- 10 mL/hr and 247 +/- 25 mL/hr in patients with prior acid-reducing surgery. A basal volume criteria of > 160 mL/hr in patients without prior acid-reducing surgery occurred in > 86% of patients, and > 140 mL/hr in 87% of patients with prior acid-reducing surgery; these, thus, are neglected findings that have good sensitivities. Our analysis shows criteria based on MAO, pH, and BAO/MAO ratio do not have high sensitivities and thus are not useful. In patients without prior acid-reducing surgery, the criteria of BAO > or = 15 mEq/hr, BAC/MAC ratio > or = 0.6, and basal gastric volume > 160 mL/hr are useful for the diagnosis of ZES and have good specificities. In patients with prior acid-reducing surgery, the criteria of BAO > or = 5 mEq/hr, BAC/MAC ratio > or = 0.6, and basal gastric volume > 140 mL/hr have high sensitivities. In patients with sporadic ZES without acid-reducing surgery, the criterion of BAO > or = 18 mEq/hr is recommended as it has a similar sensitivity but higher specificity than the criterion of BAO > or = 15 mEq/hr. Only 1 patient in either data set (NIH or the literature) with or without previous acid-reducing surgery had a basal gastric pH > 2, therefore this finding essentially excludes the diagnosis of ZES. Gastric secretory measurements for 30 minutes, but not 15 minutes, give results comparable to those for a full hour. On the basis of these results, a number of gastric secretory criteria are proposed, including some for the first time, and alterations in methodology are proposed that should prove useful in the diagnosis of ZES.

Famotidine in the therapy of gastric hypersecretory states.

The histamine (H2)-receptor antagonist famotidine was compared with ranitidine and cimetidine in its ability to control gastric acid hypersecretion in 33 patients with gastric hypersecretory states (32 patients with Zollinger-Ellison syndrome and one patient with idiopathic hypersecretion). Equipotent doses of each drug were determined in nine patients and used to determine relative onset of action, duration of action, and potency. Each drug had a similar time course of onset with a maximal effect at three to four hours after oral ingestion. The duration of action of famotidine was 30 percent longer than that of either cimetidine or ranitidine. In terms of relative potency, famotidine was nine times more potent than ranitidine and 32 times more potent than cimetidine. Thirty-two patients underwent long-term famotidine treatment for up to 34 months (mean, 10 months) with a duration in 21 patients of at least six months, in nine patients of at least 12 months, and in six patients of at least 24 months. The mean daily maintenance dose with famotidine was 0.33 g per day (range, 0.05 to 0.8 g). Prior to famotidine therapy, 27 patients were taking ranitidine and the mean daily dose required was 2.3 g per day (range, 0.6 to 5.4 g), whereas six patients were taking cimetidine and the mean daily dose was 4.6 g per day (range, 1.2 to 9.0 g). Fourteen of the 32 patients required an anticholinergic agent in addition to ranitidine or cimetidine to maintain control, whereas only five patients required an anticholinergic agent with famotidine. Gastric acid hypersecretion was controlled in seven patients with less frequent dosing with famotidine than with cimetidine or ranitidine. Long-term treatment with famotidine was not associated with any hematologic or biochemical toxicity or clinical side effects. These results demonstrate that famotidine has a similar onset of action to other H2-receptor antagonists but has a 30 percent longer duration of action and is nine times more potent than ranitidine and 32 times more potent than cimetidine. Famotidine is safe and highly effective in the long-term treatment of gastric hypersecretory states.

Zollinger-Ellison syndrome. Recognition and management of acid hypersecretion.

Zollinger-Ellison syndrome (ZES) should be suspected if a patient has severe peptic ulceration, ulcers and kidney stones, a family history of ulcers or endocrine diseases, watery diarrhoea or malabsorption with or without ulcers, or if hypergastrinaemia is found. Any patient in whom ZES is suspected, and certainly if diagnosed, should be given large doses of antisecretory medication immediately. This should never be stopped except under controlled conditions or unless acid outputs have been reduced surgically. Patients cannot be managed safely without measuring acid outputs. These should be lowered to < 10 mmol/h, or < 5 mmol/h in patients with a previous gastric resection or severe oesophageal disease. Acid secretion can be controlled acutely in 70% of patients with an infusion of ranitidine 1 mg/kg/h, while 4 mg/kg/h will control acid in all. The initial oral dosage of omeprazole or lansoprazole should be 60 mg/day. Doses should then be adjusted daily on the basis of acid outputs. Proton pump inhibitors in a dosage of 60 mg/day will control acid output in most patients and 60 mg every 12 hours will control acid output in all. Doses can then often be slowly and progressively reduced. A parietal cell vagotomy reduces acid secretion and reduces, but does not abolish, the need for antisecretory medication. In patients with multiple endocrine neoplasia type 1 and hyperparathyroidism, a parathyroidectomy that results in normocalcaemia will reduce acid secretion and drug requirements. A total gastrectomy is rarely if ever needed nowadays. Given the high degree of safety of gastric antisecretory medications versus the risks of acid hypersecretion in patients with ZES, the mistakes in management of acid hypersecretion that must be avoided are those of giving insufficient medication and not measuring acid secretory rates.

Laboratory diagnosis of gastrinoma. I. A prospective evaluation of gastric analysis and fasting serum gastrin levels.

In a small percentage of patients with ulcer disease, a gastrinoma may be ultimately discovered. In most institutions, a fasting serum gastrin determination and gastric analysis are as first-line tests to identify this subgroup of patients with ulcer disease. The blood test is relatively inexpensive and well accepted by patients. Gastric analysis is uncomfortable and required a well-equipped facility staffed by skilled personnel. A prospective study designed to assess the diagnostic usefulness of these tests and, particularly, whether combining both tests adds to the individual value of each, revealed that gastric analysis does not improve the diagnostic ability of the fasting serum gastrin test. Therefore, gastric analysis probably is not indicated for determining whether a patient with active ulcer disease has a gastrinoma. The fasting serum gastrin test will suffice, and abnormal values on this test should be verified by the use of other tests such as responses to gastrin provocative tests.

Relationship between fundic endocrine cells and gastric acid secretion in hypersecretory duodenal ulcer diseases.

BACKGROUND: Acid hypersecretion is associated with duodenal ulcer disease in the following conditions: Zollinger-Ellison syndrome (ZES) and antral gastrin cell hyperfunction (AGCH) due to hypergastrinaemia, or hypersecretory duodenal ulcer (HDU) without hypergastrinaemia. AIM: To evaluate whether quantitative changes in fundic ECL and D cells may be involved in acid hypersecretion. PATIENTS AND METHODS: Seven ZES, six AGCH and six HDU Helicobacter pylori-positive patients were compared. Basal (BAO) and pentagastrin-stimulated gastric acid secretions (PAO), and morphometry of fundic ECL and D cells were performed. The six AGCH and six HDU patients were investigated again using the same tests 1 year after H. pylori eradication. RESULTS: Median PAO values were no different in all the hypersecretory conditions studied. The median volume density of ECL cells in ZES was significantly higher than in controls (2.75, range 1.74-5.8 vs. 0.73, 0.52-1.11: P < 0.05), whereas it was in the control range in AGCH and HDU patients (0.77, range 0.20-1.39 and 0.99, range 0.42-1.51; respectively). The count of fundic D cells was significantly lower in AGCH patients than in all other investigated groups (median 0.16, range 0.1-0.52; P < 0.05). Cure of infection in AGCH and HDU patients did not modify the ECL cell volume density, whereas a significant increase in the count of fundic D cells was observed in AGCH patients. Thus, the ECL/D cell index was significantly affected in AGCH patients (P < 0.05), being higher during H. pylori infection (median 6, range 0.7-9.25) than after the cure (median 2.12, range 1.10-3.5). BAO and PAO were not affected by H. pylori eradication in either group. CONCLUSIONS: The study provides evidence, for the first time, that quantitative alterations in the fundic endocrine cells are not involved in acid hypersecretion of patients with hypersecretory states, and that eradication of H. pylori does not restore normal acid secretion values.

Effect of propranolol on secretin-induced gastrin release and secretin-induced tachycardia in patients with the Zollinger-Ellison syndrome.

The mechanism for secretin-induced gastrin release in the Zollinger-Ellison syndrome is uncertain. We evaluated whether the stimulatory effect of intravenous secretin on gastrin release was partly mediated through a beta-adrenergic stimulatory mechanism. Serum gastrin concentrations and heart rate were monitored in six patients with the Zollinger-Ellison syndrome. Secretin (2 clinical units/kg) increased mean serum gastrin concentrations from 1558 pg/ml basally to a peak of 3683 pg/ml (136% above baseline). This increase was not altered by pretreatment with 2 mg of propranolol intravenously, a dose which in previous studies blocked terbutaline-induced gastrin release. Secretin increased heart rate by 14 beats/min (20% above base-line) and this also was not altered by propranolol pretreatment. Thus, the stimulatory effects of secretin on gastrinoma cells and the heart do not appear to be mediated by beta-adrenergic receptors.

Gastric carcinoid tumors in multiple endocrine neoplasia-1 patients with Zollinger-Ellison syndrome can be symptomatic, demonstrate aggressive growth, and require surgical treatment.

BACKGROUND: Gastric carcinoid tumors occur in 15% to 50% of patients with multiple endocrine neoplasia-1/Zollinger-Ellison syndrome (MEN-1/ZES) but are thought to be benign. We report 5 patients with MEN-1/ZES with symptomatic, aggressive gastric carcinoid tumors that required surgical procedures. METHODS: This was a retrospective chart review. RESULTS: Each patient had MEN-1/ZES. Each patient had innumerable gastric carcinoid tumors with symptoms. The fasting gastrin level was 47,000 pg/mL (normal, <200 pg/mL); the basal acid output was 79 mEq/hr (n = 3), and the age at surgical exploration was 47 +/- 6 years, with a duration of MEN-1 of 21 +/- 3 years and of ZES of 15 +/- 2 years. All patients had elevated 5-HIAA or serotonin levels. Somatostatin receptor scintigraphy showed increased stomach uptake in 4 patients (80%). Four patients had a total gastrectomy; 4 patients had lymph node metastases removed, and 3 patients had liver metastases resected. One patient who did not have a total gastrectomy had liver carcinoid metastases. CONCLUSIONS: These results demonstrate that gastric carcinoid tumors in patients with longstanding MEN-1/ZES may be symptomatic, aggressive, and metastasize to the liver. With increased long-term medical treatment and life expectancy, these tumors will become an important determinant of survival.

Pulsatile activation of the hypothalamic-pituitary-adrenal axis during major surgery.

To examine the response of the hypothalamic-pituitary-adrenal (HPA) axis to severe surgical stress, we measured the immunoreactive plasma levels of corticotropin-releasing hormone (CRH), corticotropin, cortisol, arginine-vasopressin (AVP), atrial natriuretic factor (ANF), neuropeptide Y (NPY), interleukin-1 (IL-1), IL-6, interferon gamma (INF), and tumor necrosis factor-alpha (TNF-alpha) in eight patients with Zollinger-Ellison syndrome (ZES) or mediastinal parathyroid carcinoma, all undergoing major surgery with a standardized anesthetic technique. Blood samples were drawn the morning before surgery, every 10 to 30 minutes throughout surgery (average, 308.7 +/- 15 minutes), and every morning for the next 4 postoperative days (POD). During surgery, plasma CRH concentrations were slightly but not significantly elevated compared with those before surgery and with those of the next 4 POD. However, the values were within the normal range (less than 2.2 pmol/L) and showed 8.9 +/- 0.6 pulses (one pulse every 34.7 +/- 1.6 minutes). Plasma corticotropin, on the other hand, was quite elevated, but was also released in a pulsatile fashion during the surgical procedure (one pulse every 36.7 +/- 1.6 minutes). Most of these secretory episodes of corticotropin were temporally related to those of CRH. Corticotropin returned to basal levels on the first POD and remained so for all 4 POD. Plasma cortisol concentrations increased steadily during surgery and remained elevated the first POD. Cortisol showed 6.2 +/- 1.1 pulses during the operative sampling period (one pulse every 71.8 +/- 13 minutes). Plasma AVP concentrations were also markedly elevated during surgery, but individual secretory pulses were not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

The natural history of multiple endocrine neoplasia type 1. Highly uncommon or highly unrecognized?

Among 2000 descendants of an English immigrant to Tasmania, Australia, the diagnosis of multiple endocrine neoplasia type 1 was found to be very highly probable or highly probable in 130 and moderately probable in 22. Another 242 children and siblings were 50% likely to have inherited this dominant gene. In all age groups, especially the elderly, the majority of affected members had symptoms of only one endocrine disorder or were asymptomatic. In teenagers, the most common presentation was pituitary lesions and the second most common presentation was insulinomas. Frequently, pituitary lesions or insulinomas developed before any parathyroid lesions could be detected. Elevation of gastrin levels, usually associated with hypercalcemia, was rarely seen in patients younger than 25 years. The classic presentation with symptoms of multiple endocrinopathy may represent only a small fraction of these patients in the community.

Zollinger-Ellison syndrome.

As clinical experience with patients with ZES has grown, increasing recognition has been made of the broad spectrum of symptoms associated with gastrinomas. Diarrhea and acid-induced esophageal injury have taken their place alongside chronic peptic ulcer disease as indications for screening for gastrinoma. Diagnostic testing should begin with fasting serum gastrin levels and should include intravenous secretin infusion if fasting serum levels of gastrin are nondiagnostic and the patient is not found to be hypochlorhydric. Tumor localization is critical to aid in the identification of patients with potentially curable localized disease. Preoperative evaluation utilizing CT scanning with intravenous contrast should be done early and should be supplemented by other imaging modalities as necessary. Exploratory laparotomy, including a thorough examination of the duodenum and perhaps intraoperative ultrasound, should be performed in all patients with sporadic gastrinoma who lack evidence of extensive metastatic disease on preoperative evaluation. By utilizing this approach, it is likely that at least 20% of patients with ZES can be cured. With the availability of the highly effective H(+)-K(+)-ATPase inhibitor omeprazole, excellent control of symptoms related to gastric acid hypersecretion can be expected. Patients with unresectable gastrinoma may thus avoid potentially morbid antisecretory surgery and be managed with a fairly simple medical regimen. Further developments in the chemotherapeutic management of these patients with unresectable disease should be forthcoming in the future.