Determinants of metastatic rate and survival in patients with Zollinger-Ellison syndrome: a prospective long-term study

Early surgical intervention and strategy in patients with multiple endocrine neoplasia type 1

Patients with multiple endocrine neoplasia type 1 (MEN-1) are an unusual challenge to the endocrine surgeon. Pituitary disease is often treated without surgery, but nearly all patients will require parathyroidectomy for parathyroid hyperplasia. Subtotal parathyroidectomy can be accomplished with a very low rate of permanent hypoparathyroidism and an acceptable rate of recurrent hyperparathyroidism. The treatment of pancreaticoduodenal disease is quite controversial. Even when associated with the Zollinger-Ellison syndrome, early and aggressive surgical treatment should be considered to influence the hormonal syndrome as well as to address the malignant potential of both pancreatic and duodenal tumours. This includes distal pancreatectomy, enucleation of pancreatic head lesions, and duodenotomy with the resection of gastrinomas. Many patients may be completely cured of the manifestations of their disease. As MEN-1 is an uncommon entity, there are very few prospective, randomized data upon which to base surgical judgements.

The surgical management of pancreatic neuroendocrine tumors

NETs of pancreas are rare and may or may not be associated with symptoms of hormone overproduction. Treatment is required for control of tumor growth and for relief of symptoms associated with excess hormone. With advances in the nonsurgical management of many hormone-related symptoms (e.g., proton pump inhibitors or somatostatin analogues), care for many of these patients has shifted toward the control of tumor progression. Complete surgical resection is the only curative treatment for these tumors. With improvements in the preoperative imaging and intraoperative localization techniques, it is hoped that these tumors will be identified and resected for cure with increased frequency. For patients with hepatic metastasis, initial expectant observation and medical management of symptoms is appropriate in view of the long and indolent course of the disease. Hepatic arterial embolization is the preferred mode of palliation for pain and hormonal symptoms. A curative hepatic resection may be possible in selected patients.

Multiple endocrine neoplasia type 1: new clinical and basic findings

Multiple endocrine neoplasia type 1 (MEN1) provides a prime example of how a rare disease can advance our understanding of basic cell biology, neoplasia and common endocrine tumors. MEN1 is expressed mainly as parathyroid, enteropancreatic neuroendocrine, anterior pituitary and foregut carcinoid tumors. It is an autosomal dominant disease caused by mutation of the MEN1 gene. Since its identification, the MEN1 gene has been implicated in many common endocrine and non-endocrine tumors. This is a brief overview of recent scientific advances relating to MEN1, including newly recognized clinical features that are now better characterized by genetic analysis, insights into the function of the MEN1-encoded protein menin, and refined recommendations for mutation testing and tumor screening, which highlight our increasing understanding of this complex syndrome.

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.

A new cause of Zollinger-Ellison syndrome: non-small cell lung cancer

Numerous epidemiologic studies suggest a relationship between lung cancer and peptic ulcer disease. Furthermore, various lung cancers synthesize and release a number of peptides such as gastrin and gastrin-releasing peptide that could cause acid hypersecretion; however, Zollinger-Ellison syndrome (ZES), because of a lung tumor, has never been described. We report such a patient for the first time. A 60-year-old man with a non-small cell lung carcinoma (large cell type) presented with diarrhea, heartburn, abdominal pain, and duodenal ulcers. Evaluation showed ZES was present (fasting hypergastrinemia, hyperchlorhydria) and control of all symptoms by omeprazole. No abdominal or cardiac tumor, the other known locations of gastrinomas causing ZES, was found on detailed tumor imaging studies. Resection of the lung tumor resulted in a decrease in gastrin levels to normal values. Plasma radioimmunoassays showed elevated gastrin, chromogranin A and normal levels of gastrin-releasing peptide, and 9 other hormones. The tumor showed similar immunocytochemical results. The characteristics of this case are compared with 100 cases of sporadic abdominal gastrinomas, and the evidence reviewed suggests why ZES should be considered in patients with lung cancer with peptic symptoms.

Malignant endocrine tumors in patients with MEN 1 disease

BACKGROUND

In contrast with multiple endocrine neoplasia type 2, malignancies are of minor importance in multiple endocrine neoplasia type 1 (MEN 1) syndrome.

METHODS

The data for 42 patients with MEN 1 syndrome were evaluated. Twelve patients (29%) had 1 or more associated malignancies: malignant gastrinoma (1 patient), neuroendocrine tumors of the thymus (2 patients), neuroendocrine tumors of the lung (3 patients), neuroendocrine tumor of the ileum (1 patient), adrenocortical carcinomas (2 patients), and a combination of neuroendocrine tumors of thymus, lung or pancreas (3 patients).

RESULTS

Despite suspected MEN 1 syndrome in 7 patients, malignancies were detected late in 4 patients and could not be resected curatively. The survival rates for 5 years and 10 years after operation of the malignant tumor were 66% +/- 14% (SE) and 33% +/- 15% (SE), respectively.

CONCLUSIONS

In patients at risk for the MEN 1 syndrome, genetic screening is indispensable. Gene carriers have to be followed up closely with hormone analysis and routine examination of the thorax, pancreas, and adrenal glands to detect malignancies as early as possible.

Zollinger-Ellison syndrome. Clinical presentation in 261 patients

We prospectively evaluated the initial presenting symptoms in 261 patients with Zollinger-Ellison syndrome (ZES) over a 25-year period. Twenty-two percent of the patients had multiple endocrine neoplasia-type 1 (MEN-1) with ZES. Mean age at onset was 41.1 +/- 0.7 years, with MEN-1 patients presenting at a younger age than those with sporadic ZES (p < 0.0001). Three percent of the patients had onset of the disease < age 20 years, and 7% > 60 years. A mean delay to diagnosis of 5.2 +/- 0.4 years occurred in all patients. A shorter duration of symptoms was noted in female patients and in patients with liver metastases. Abdominal pain and diarrhea were the most common symptoms, present in 75% and 73% of patients, respectively. Heartburn and weight loss, which were uncommonly reported in early series, were present in 44% and 17% of patients, respectively. Gastrointestinal bleeding was the initial presentation in a quarter of the patients. Patients rarely presented with only 1 symptom (11%); pain and diarrhea was the most frequent combination, occurring in 55% of patients. An important presenting sign that should suggest ZES is prominent gastric body folds, which were noted on endoscopy in 94% of patients; however, esophageal stricture and duodenal or pyloric scarring, reported in numerous case reports, were noted in only 4%-10%. Patients with MEN-1 presented less frequently with pain and bleeding and more frequently with nephrolithiasis. Comparing the clinical presentation before the introduction of histamine H2-receptor antagonists (pre-1980, n = 36), after the introduction of histamine H2-receptor antagonists (1981-1989, n = 118), and after the introduction of proton pump inhibitors (PPIs) (> 1990, n = 106) demonstrates no change in age of onset; delay in diagnosis; frequency of pain, diarrhea, weight loss; or frequency of complications of severe peptic disease (bleeding, perforations, esophageal strictures, pyloric scarring). Since the introduction of histamine H2-receptor antagonists, fewer patients had a previous history of gastric acid-reducing surgery or total gastrectomy. Only 1 patient evaluated after 1980 had a total gastrectomy, and this was done in 1977. The location of the primary tumor in general had a minimal effect on the clinical presentation, causing no effect on the age at presentation, delay in diagnosis, frequency of nephrolithiasis, or severity of disease (strictures, perforations, peptic ulcers, pyloric scarring). Disease extent had a minimal effect on symptoms, with only bleeding being more frequent in patients with localized disease. Patients with advanced disease presented at a later age and with a shorter disease history (p = 0.001), were less likely to have MEN-1 (p = 0.0087), and tended to have diarrhea more frequently (p = 0.079). A correct diagnosis of ZES was made by the referring physician initially in only 3% of the patients. The most common misdiagnosis made were idiopathic peptic ulcer disease (71%), idiopathic gastroesophageal reflux disease (GERD) (7%), and chronic idiopathic diarrhea (7%). Other less common misdiagnosis were Crohn disease (2%) and various diarrhea diseases (celiac sprue [3%], irritable bowel syndrome [3%], infectious diarrhea [2%], and lactose intolerance [1%]). Other medical disorders were present in 55% of all patients; patients with sporadic disease had fewer other medical disorders than patients with MEN-1 (45% versus 90%, p < 0.00001). Hyperparathyroidism and a previous history of kidney stones were significantly more frequent in patients with MEN-1 than in those with sporadic ZES. Pulmonary disorders and other malignancies were also more common in patients with MEN-1. These results demonstrate that abdominal pain, diarrhea, and heartburn are the most common presenting symptoms in ZES and that heartburn and diarrhea are more common than previously reported. The presence of weight loss especially with abdominal pain, diarrhea, or heartburn is an important clue suggesting the presence of gastrinoma. The presence of prominent gastric body folds, a clinical sign that has not been appreciated, is another important clue to the diagnosis of ZES. Patients with MEN-1 presented at an earlier age; however, in general, the initial symptoms were similar to patients without MEN-1. Gastrinoma extent and location have minimal effects on the clinical presentation. Overall, neither the introduction of successful antisecretory therapy nor widespread publication about ZES, attempting to increase awareness, has shortened the delay in diagnosis or reduced the incidence of patients presenting with peptic complications. The introduction of successful antisecretory therapy, however, has dramatically decreased the rate of surgery in controlling the acid secretion and likely led to patients presenting with less severe symptoms and fewer complications. (ABSTRACT TRUNCATED)

Expression of the calcium-sensing receptor in gastrinomas

Extracellular calcium levels are able to influence the secretion of gastrin by gastrinomas and possibly affect the growth pattern. The molecular mechanisms of these functions are not known. The purpose of the present study was to investigate the presence of the calcium-sensing receptor (CaR) in 10 gastrinomas and determine the extent of expression in the tumors. The amounts of CaR messenger ribonucleic acid in eight tumors were determined by quantitative RT-PCR. Protein expression was analyzed by Western blot and immunohistochemistry using a monoclonal antibody (ADD). CaR messenger ribonucleic acid was detected in all gastrinomas with levels ranging from 0.04-3.16 times the amount of beta-actin transcripts. The Western blot showed a major immunoreactive band at 250 kDa and a minor at 140 kDa, corresponding to the receptor dimer and monomer, respectively. Immunohistochemistry demonstrated variable membranous staining in all gastrinomas and normal pancreatic islets. No staining was observed in the normal liver, lymph node, or exocrine pancreas. We conclude that the CaR is present in all gastrinomas, with expression varying by 80-fold. It probably contributes to the calcium-stimulated gastrin release by gastrinomas. Whether the density of the CaR is a determining factor of the magnitude of this gastrin release or plays a role in regulating the growth pattern of the gastrinoma, as it does in other cells, remains unclear at present.

Phenotype and phenocopy: the relationship between genotype and clinical phenotype in a single large family with multiple endocrine neoplasia type 1 (MEN 1)

BACKGROUND

The majority of reports describing the natural history and prognosis of multiple endocrine neoplasia type 1 (MEN 1) utilize phenotypic rather than molecular genetic criteria to establish a diagnosis of MEN 1.

OBJECTIVES AND PATIENTS

We sought to determine the spectrum of endocrine abnormality amongst 152 members (64 gene carriers and 88 noncarriers) of a large MEN 1 family in whom a determination of MEN 1 status had previously been made by phenotype screening. The predictive utility of both clinical and molecular screening techniques are described.

RESULTS

A novel IVS2-3 (C-G) MEN1 mutation was identified in affected members of this family. Seven (10%) of 71 individuals satisfying clinical diagnostic criteria for MEN 1 were found to be genetically negative (excluded by mutation analysis and haplotyping) for MEN 1. These cases of MEN 1 phenocopy comprised four cases of primary hyperparathyroidism, two 'nonsecretory' pituitary adenoma and one case of coincident prolactinoma and hyperparathyroidism. Three of the patients with hyperparathyroidism had previously required parathyroidectomy and each had achieved normocalcaemia following parathyroid resection. Predictive genetic testing prospectively identified three children with the MEN 1 genotype. Serum calcium was normal at the time of their initial molecular genetic diagnosis. In each case hyperparathyroidism subsequently developed during adolescence.

CONCLUSION

Multiple endocrine neoplasia type 1 phenocopy is an important differential diagnosis in patients exhibiting an multiple endocrine neoplasia type 1 phenotype. This is a relevant consideration, particularly when the diagnosis of multiple endocrine neoplasia type 1 is made using sensitive, but nonspecific, criteria such as mild hyperparathyroidism, pituitary micoadenoma, and hyperprolactinaemia. Confirmatory genetic testing should be undertaken to confirm clinical diagnoses of multiple endocrine neoplasia type 1.

Carcinoid and pancreatic endocrine tumors: recent advances in molecular pathogenesis, localization, and treatment

Neuroendocrine tumors include carcinoids and pancreatic endocrine tumors, which share a number of common features in their pathology, ability to cause clinical symptoms due to ectopic hormone and bioamine release, localization methods, and treatment. Although generally slow growing, a proportion demonstrate aggressive tumor growth. Therefore, in many cases treatment must be directed against both the tumor and the hormone-excess state. There have been significant recent advances into their molecular pathogenesis, natural history, and prognostic factors; clinical presentation defined by larger series analysis; localization methods; and the development of new treatments directed against the tumor and to control the hormone-excess state (including depot somatostatin analogues, interferon combinations, embolization, chemoembolization, radiotherapy with novel somatostatin analogues, and liver transplantation). Recent advances in each of these areas are briefly discussed.

Multiple endocrine neoplasias

Multiple endocrine neoplasia type 1 (MEN 1), and the multiple endocrine neoplasia type 2 syndromes (MEN 2A, MEN 2B, and familial non-MEN medullary thyroid carcinoma [FMTC]) encompass a wide range of endocrine problems, but arise from only two genes: the MEN 1 tumor suppressor gene and the RET proto-oncogene. MEN 1 is characterized by parathyroid hyperplasia, pancreaticoduodenal neuroendocrine tumors (PNTs), and pituitary adenomas. Surgery is the principal treatment modality for hyperparathyroidism and PNTs, but questions still remain concerning the timing and extent of surgery for PNTs. The MEN 2 syndromes are characterized by complete penetrance of medullary thyroid cancer. The MEN 2 syndromes differ in their variable expression of hyperparathyroidism, pheochromocytomas, and other clinical features. Genetic testing for mutations in the RET gene has revolutionized treatment by enabling thyroidectomies before significant disease occurs.

Primary nodal gastrinomas

BACKGROUND

The term primary lymph node gastrinoma was first used to describe a group of patients with gastrin-producing tumors present in lymph nodes located in a well-defined anatomic region. The patients had no known primary tumors in the pancreas or gastrointestinal tract and had disease-free survival for up to 18 years. The anatomic region in question has a triangular shape that extends from the cystic and common bile ducts to the second and third portion of the duodenum and the neck and body of the pancreas. The term gastrinoma triangle was coined to identify the area; in addition, it was postulated that lymph nodes located in the gastrinoma triangle normally contained neuroendocrine cells capable of secreting gastrin and other neuropeptides. From its inception, the postulate became the subject of controversy.

DESIGN

To extend previous observations, we examined the lymph nodes located in the gastrinoma triangle of 20 autopsy cases for the presence of neuroendocrine cells, as determined by immunohistochemistry, using antibodies to a panneuroendocrine substance (eg, synaptophysin) and a specific neuropeptide (eg, gastrin). Scanning for positive cells was performed by 2 observers (M.E.H. and M.C.C.). We compared the findings in these lymph nodes with lymph nodes obtained from axillary and inguinal dissections during surgical procedures.

RESULTS

In all, 417 lymph nodes were studied. Five of the 20 gastrinoma triangle cases contained synaptophysin reactive cells, whereas 3 had gastrin reactive cells. None of the axillary and inguinal lymph nodes contained neuroendocrine cells.

CONCLUSION

Our findings support the hypothesis of entrapment of neuroendocrine cells during development and the presence of primary nodal gastrinomas.

Duodenopancreatic resections in patients with multiple endocrine neoplasia type 1

OBJECTIVE

To review the authors' 7-year experience with a surgical approach for pancreatic and duodenal neuroendocrine tumors (NETs) in patients with multiple endocrine neoplasia type 1 (MEN 1) designed to remove all gross tumor with limited complications, preserving pancreatic function.

SUMMARY BACKGROUND DATA

MEN 1 is an autosomal dominant familial neoplasia syndrome characterized by the development of NETs of the duodenum and pancreas. Some tumors are clinically insignificant or follow a benign course, although a subset pursues a malignant, lethal natural history; the risk of surgical management must be appropriate to the disease course.

METHODS

The clinical, biochemical, genetic, and pathologic data were retrospectively reviewed for 21 consecutive MEN 1 patients undergoing pancreatic resection for NETs between 1993 and 1999 at one institution. Age at operation, presenting symptoms, results of preoperative and intraoperative localization studies, major and minor complications, and pathology, including metastases, were analyzed.

RESULTS

The surgical approach was selected based on the location and size of the tumors. Five patients required pancreaticoduodenectomy, 11 patients underwent non-Whipple pancreatic resections, and 5 underwent simple enucleation of benign NETs. The incidence of regional lymph node metastases was 33%.

CONCLUSIONS

Major pancreatic procedures can be performed safely in most patients with MEN 1 and NETs. Because NETs are the most common MEN 1-related cause of death in the authors' kindreds, an aggressive surgical approach, including early intervention before malignant spread and major pancreatic resection where indicated, appears justified.

Intravenous pantoprazole rapidly controls gastric acid hypersecretion in patients with Zollinger-Ellison syndrome

BACKGROUND & AIMS

Parenteral control of gastric acid hypersecretion in conditions such as Zollinger-Ellison syndrome (ZES) or idiopathic gastric acid hypersecretion is necessary perioperatively or when oral medications cannot be taken for other reasons (e.g., during chemotherapy, acute upper gastrointestinal bleeding, or in intensive care unit settings).

METHODS

We evaluated the efficacy and safety of 15-minute infusions of the proton pump inhibitor pantoprazole (80-120 mg every 8-12 hours) in controlling acid output for up to 7 days. Effective control was defined as acid output >10 milliequivalents per hour (mEq/h) (<5 mEq/h in patients with prior acid-reducing surgery) for 24 hours.

RESULTS

The 21 patients enrolled had a mean age of 51.9 years (range, 29-75) and a mean disease duration of 8.1 years (range, <0.5-21); 13 were male, 7 had multiple endocrine neoplasia syndrome type I, 4 had undergone acid-reducing surgery, 2 had received chemotherapy, and 13 had undergone gastrinoma resections without cure. Basal acid output (mean +/- SD) was 40.2 +/- 27.9 mEq/h (range, 11.2-117.9). In all patients, acid output was controlled within the first hour (mean onset of effective control, 41 minutes) after an initial 80-mg intravenous pantoprazole dose. Pantoprazole, 80 mg every 12 hours, was effective in 17 of 21 patients (81%) for up to 7 days. Four patients required upward dose titration, 2 required 120 mg pantoprazole every 12 hours, and 2 required 80 mg every 8 hours. At study end, acid output remained controlled for 6 hours beyond the next expected dose in 71% of patients (n = 15); mean acid output increased to 4.0 mEq/h (range, 0-9.7). No serious or unexpected adverse events were observed.

CONCLUSIONS

Intravenous pantoprazole, 160-240 mg/day administered in divided doses by 15-minute infusion, rapidly and effectively controlled acid output within 1 hour and maintained control for up to 7 days in all ZES patients.

Personal review: is profound acid inhibition safe?

Inhibitors of gastric acid secretion, particular proton pump inhibitors, are effective drugs in the treatment and prophylaxis of acid-related diseases. Proton pump inhibitors are therefore prescribed widely, often for minor complaints. Gastric acidity kills swallowed microorganisms, and acid secretion must be of biological importance because it is maintained in phylogenesis. Acid secretion is controlled by feedback mechanisms, mainly via gastrin. A decrease in acidity always causes an increase in plasma gastrin. The trophic effect of gastrin leads to hyperplasia and neoplasia of the enterochromaffin-like (ECL) cell. ECL cell derived tumours in man were previously regarded as rare, and also as rather benign. It is now clear that the ECL cell gives rise to a significant proportion of gastric carcinomas. Moreover, ECL cell carcinoids secondary to hypergastrinaemia may develop into highly malignant tumours. Treatment with a proton pump inhibitor is followed by rebound acid hypersecretion and decreased efficiency of H2-blockers, thus such treatment may induce a type of physical dependence. It is therefore reasonable to be cautious and not to treat younger (< 50 years) patients for long periods of time with profound inhibitors of gastric acid secretion. Chromogranin A in the blood is a sensitive marker of the ECL cell mass, and it could be used to survey patients on long-term proton pump inhibitors.

Protocol for the examination of specimens from patients with endocrine tumors of the pancreas, including those with mixed endocrine and acinar cell differentiation: a basis for checklists. Cancer Committee of the College of American Pathologists

No Abstract Available

Surgery to cure the Zollinger-Ellison syndrome

BACKGROUND AND METHODS

The role of surgery in patients with the Zollinger-Ellison syndrome is controversial. To determine the efficacy of surgery in patients with this syndrome, we followed 151 consecutive patients who underwent laparotomy between 1981 and 1998. Of these patients, 123 had sporadic gastrinomas and 28 had multiple endocrine neoplasia type 1 with an imaged tumor of at least 3 cm in diameter. Tumor-localization studies and functional localization studies were performed routinely. All patients underwent surgery according to a similar operative protocol, and all patients who had surgery after 1986 underwent duodenotomy.

RESULTS

The 151 patients underwent 180 exploratory operations. The mean (+/-SD) follow-up after the first operation was 8+/-4 years. Gastrinomas were found in 141 of the patients (93 percent), including all of the last 81 patients to undergo surgery. The tumors were located in the duodenum in 74 patients (49 percent) and in the pancreas in 36 patients (24 percent); however, primary tumors were found in lymph nodes in 17 patients (11 percent) and in another location in 13 patients (9 percent). The primary location was unknown in 24 patients (16 percent). Among the patients with sporadic gastrinomas, 34 percent were free of disease at 10 years, as compared with none of the patients with multiple endocrine neoplasia type 1. The overall 10-year survival rate was 94 percent.

CONCLUSIONS

All patients with the Zollinger-Ellison syndrome who do not have multiple endocrine neoplasia type 1 or metastatic disease should be offered surgical exploration for possible cure.

[Multiple endocrine neoplasia Type I. Diagnosis and therapy in a case with classical family history]

BACKGROUND

A classical family history, representative of the multiple endocrine neoplasia type I (MEN I) syndrome, is reported to illustrate the clinical manifestations, diagnostic procedures and therapeutic modalities of the various endocrine disorders of this syndrome.

DIAGNOSIS

Today genetic analysis clearly identifies gene carriers. In these patients screening of all involved endocrine organs (parathyroid, pituitary, pancreas) at regular time intervals is necessary because also at higher ages additional endocrine manifestations may develop. Due to consequent screening the age at time of diagnosis was reduced by 10 to 20 years. As a consequence the rate of malignancy of pancreatic endocrine tumors which is the limiting factor with regard to long-term prognosis was reduced to about one third. At present it is not known whether this procedure can also increase the survival rate of MEN I patients as could be demonstrated in the MEN II syndrome.

Prospective study of the value of serum chromogranin A or serum gastrin levels in the assessment of the presence, extent, or growth of gastrinomas

BACKGROUND

Serum chromogranin A levels (CgA) are reported by some authors to be of clinical utility for assessing the presence or absence of a pancreatic endocrine tumor and tumor extent or growth. The aim of the current study was to assess this finding and compare the results with those from serum gastrin determinations (FSG) in a large cohort of patients with gastrinomas.

METHODS

In 112 consecutive patients with the Zollinger-Ellison syndrome serum CgA and FSG levels were measured and correlated with disease activity, extent of disease, and the presence of multiple endocrine neoplasia type-1 (MEN-1) or gastric carcinoid tumors.

RESULTS

Serum CgA levels drawn on 2 consecutive days correlated closely (P < 0.00001) as did serum gastrin levels. Serum CgA levels correlated significantly with FSG levels (P < 0.00001). Serum CgA and FSG levels were significantly higher in patients with active disease than in disease free patients (P < 0.00001). The sensitivity for the presence of disease was higher for CgA compared with FSG (92% vs. 80%; P = 0.021). However, the specificity of CgA was 67%. Serum CgA levels were not significantly different in the four disease categories (stable extrahepatic disease, increasing extrahepatic disease, stable liver metastases, and increasing liver metastases). FSG levels were significantly lower in patients with stable extrahepatic disease compared with those with increasing extrahepatic disease. However, both tumor markers decreased significantly with a gastrinoma resection in five patients. The presence of MEN-1 or a gastric carcinoid tumor did not influence the results.

CONCLUSIONS

The results of the current study showed that serum CgA and FSG levels both are sensitive tumor markers for the detection of a gastrinoma; however, CgA levels have a relatively low specificity. Neither the magnitude of the serum CgA nor gastrin level correlated with tumor growth or tumor extent and therefore cannot be used to determine these variables. However, in contrast to some other studies, the results of the current study show that changes in serum CgA or gastrin in a given patient with time are related to the tumor extent and not to gastric mucosal changes due to hypergastrinemia.

Prognostic factors in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. Groupe d'Etude des Néoplasies Endocriniennes Multiples (GENEM and groupe de Recherche et d'Etude du Syndrome de Zollinger-Ellison (GRESZE)

BACKGROUND & AIMS

Risk factors of metachronous liver metastases and death are not well known in patients with the Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. These factors were retrospectively determined in 77 patients.

METHODS

Data chart review was performed.

RESULTS

Median follow-up was 102 months (range, 12-366). Surgery was performed on 48 patients, including 9 of the 10 patients with large pancreatic tumors (>/=3 cm). Liver metastases developed in 4 patients (40%) with large pancreatic tumors, in 3 (4.8%) without, and in 1 of the 4 patients with pancreatic tumors of unknown size; all had previously undergone surgery. The only independent factor associated with development of liver metastases identified by multivariate analysis was large pancreatic tumors (risk ratio, 29.0; 95% confidence interval [CI], 3. 2-260.7). Surgery was not selected. The probability of being free of liver metastases in the 63 patients without large pancreatic tumors was 96% (95% CI, 88-100) at 10 and 15 years. Thirteen (16.9%) patients died. The only independent factors of death selected by multivariate analysis were Zollinger-Ellison syndrome diagnosis before 1980 (risk ratio, 8.2; 95% CI, 1.7-40.6) and age at diagnosis (risk ratio/year, 1.08; 95% CI, 1.03-1.14).

CONCLUSIONS

Large pancreatic tumors are predictive of the development of metachronous liver metastases, and surgery does not seem to prevent them.

Surgical resection of intracardiac gastrinoma

There has been only one previous report of an intracardiac gastrinoma causing Zollinger-Ellison syndrome. In this communication we describe the successful surgical resection of a gastrinoma located in the interventricular septum using cardiopulmonary bypass, blood cardioplegia, and mild hypothermia. Preoperative evaluation and histologic examination of the resected tumor strongly suggest that this was a primary intracardiac gastrinoma.

Prospective study of the clinical course, prognostic factors, causes of death, and survival in patients with long-standing Zollinger-Ellison syndrome

PURPOSE

The long-term clinical course of unselected patients with gastrinomas as well as other functional pancreatic endocrine tumors (PETs) in whom the excess-hormone state is controlled is largely unknown. To address this issue, patients with gastrinomas were assessed.

PATIENTS AND METHODS

Two hundred twelve patients with Zollinger-Ellison syndrome (ZES) were prospectively studied. All had controlled acid hypersecretion and were assessed yearly, with a mean follow-up period of 13.8+/-0.6 years (range, 0.1 to 31 years). Annual assessments of possible factors that might affect prognosis or treatment approaches were performed, such as those for tumor size and location; the presence, location, and extent of metastases; and the occurrence of ectopic Cushing's syndrome or another PET syndrome. Deaths were categorized as ZES-related or non-ZES-related and classified into different causes.

RESULTS

Thirty-one percent of patients died, all of non-acid-related causes. One half died of a ZES-related cause; they differed from those who died of non-ZES deaths by having a large primary tumor, more frequently a pancreatic tumor; lymph node, liver, or bone metastases; ectopic Cushing's syndrome; or higher gastrin levels. The extent of liver metastases correlated with survival rate. The presence of liver metastases alone only moderately decreased survival time; however, the additional development of bone metastases or ectopic Cushing's syndrome markedly decreased survival rate.

CONCLUSIONS

In ZES, gastrinoma growth is now the main single determinant of long-term survival, with one half of patients dying a gastrinoma-related death and none an acid-related death. Large primary tumors that are pancreatic in location, the development of liver metastases, (especially if associated with bone metastases or Cushing's syndrome), and the extent of liver metastases are all important prognostic factors. The identification of these factors allows the recognition of subgroups that can be used to tailor antitumor treatment approaches.

Pancreatic endocrine tumors: recent advances

Pancreatic endocrine tumors (PET's) can be divided on a clinical and pathologic basis into ten classes [insulinomas, gastrinomas (Zollinger-Ellison syndrome), VIPomas (Verner-Morrison syndrome, WDHA, pancreatic cholera), glucagonomas, somatostatinomas, ACTH-releasing tumors (ACTHomas), growth hormone-releasing factor secreting tumors (GRFomas), nonfunctioning or pancreatic polypeptide secreting tumors (non-functioning PET), PET's causing carcinoid syndrome and PET's causing hypercalcemia)]. Recent reports suggest calcitonin-secreting PET's also rarely occur but whether they cause a distinct clinical syndrome is unclear. PET's resemble carcinoid tumors histologically; in their ability to synthesize and frequently secrete multiple peptides such as neuroendocrine cell markers (chromogranins); their biologic behavior and their tumor growth patterns. Both groups of tumors are highly vascular, have high densities of somatostatin receptors and similar tumor localization studies including somatostatin receptor scintigraphy are used for both. PET's, similar to carcinoids causing the carcinoid syndrome, require two separate treatment options be considered: treatment directed against the hormone-excess state and treatment directed against the tumor per se because of their malignant nature. In the last few years there have been advances in tumor diagnosis, localization methods, treatment approaches particularly related to the use of synthetic somatostatin analogues, and the definition of the role of surgical procedures in these diseases. Important other advances include insights into the long-term natural history of PET's particularly from studies of gastrinomas, which allow prognostic factors to be identified and the timing of treatment options to better planned, as well as insights into the molecular basis of these disorders. The latter includes both a description of the molecular basis of the genetic inherited syndromes associated with PET's or carcinoid tumors, as well as an increased understanding of the molecular basis for sporadic PET's or carcinoid tumors. Each of these areas will be briefly highlighted in this presentation.

Pancreatic islet cell tumor metastasis in multiple endocrine neoplasia type 1: correlation with primary tumor size

BACKGROUND

Islet cell tumor (ICT) metastasis is one of the potentially lethal outcomes of multiple endocrine neoplasia type 1 (MEN 1). Management of ICT in patients with MEN 1 is controversial; some advocate resection based on biochemical evidence of progression, whereas others use tumor size to predict the risk of metastasis and the need for resection. This study correlates the size of primary ICT with the presence of metastases.

METHODS

Forty-eight patients with MEN 1 with ICT, from 34 kindreds followed up in our multiple endocrine neoplasia program, were evaluated; 43 of the 48 have been explored for ICT. Metastases to the lymph nodes and liver were documented.

RESULTS

Thirty-three percent of patients with pancreatic tumors less than 1 cm in greatest diameter had metastatic disease at surgery and in follow-up, whereas 34.8% of patients with tumors greater than 2 cm in diameter had metastases to lymph nodes or liver. The 2 patients with liver metastases each had primary tumors greater than 2 cm. Follow-up revealed subsequent metastasis in 1 patient.

CONCLUSIONS

The size of primary tumors in MEN 1 does not correlate with metastatic potential. This is not a good criterion for exploration. Continued follow-up of these patients will be necessary to define the effect of operation on the course of ICT in MEN 1.

Surgical treatment of localized gastrinoma within the liver: a prospective study

BACKGROUND

Studies demonstrate that liver metastases of gastrinoma significantly reduce survival.

METHODS

Since 1982 we have prospectively studied 213 patients with Zollinger-Ellison syndrome. For this report the results of surgery for localized liver gastrinoma were analyzed.

RESULTS

Zollinger-Ellison syndrome was diagnosed biochemically in all patients and acid output was controlled with medications. Imaging studies demonstrated liver gastrinoma in 69 patients (32%). Fifty-two had diffuse unresectable disease, whereas 17 (10%) had localized disease. All patients with localized liver gastrinoma and 2 patients with diffuse disease who needed surgery are the subject of this report. Major hepatic lobectomy was performed in 10 patients and wedge resections in 9. Three patients had apparent liver primary gastrinomas and 16 had metastatic disease. Seventeen of 19 patients were able to have all identifiable gastrinoma resected. Extrahepatic tumor was also removed at the same procedure. Extirpation of liver gastrinoma required hepatic lobectomy in 10 patients and wedge resections in the others. Five-year survival was 85%. Five of 17 completely resected patients (29%) remained disease free.

CONCLUSIONS

Resectable localized liver gastrinoma is rare. Primary liver gastrinomas can occur. Surgical resection of localized liver gastrinoma provides a cure rate similar to that of extrahepatic gastrinoma and an excellent long-term survival.

Analysis of factors associated with long-term (five or more years) cure in patients undergoing operation for Zollinger-Ellison syndrome

BACKGROUND

Only 30% to 40% of patients with Zollinger-Ellison syndrome (ZES) undergoing operation with curative intent have biochemical cures. The purpose of this analysis was to identify perioperative factors associated with long-term (> or = 5 years) biochemical cures.

METHODS

From December 1981 to September 1997, 128 patients with potentially curable ZES underwent 152 abdominal explorations with resection of all identifiable disease. Of these, 31 outcomes were identified with documented cures at > or = 5 years from operation and were compared with outcomes of 110 patients who were not cured. Univariate and multivariate statistical analyses were performed.

RESULTS

The results of a normal immediate postoperative fasting serum gastrin and secretin stimulation test were significantly and independently correlated with 5-year cure (P2 = .005 and .0099, respectively). A diagnosis of multiple endocrine neoplasia type 1 was significantly inversely correlated with cure on univariate analysis (P2 = .027). Gender, age, duration of symptoms, results of diagnostic tests, or results of imaging studies did not correlate with outcome.

CONCLUSIONS

All patients with sporadic potentially curable ZES should undergo exploration because outcome is not associated with preoperative tests. Only 5% of patients with ZES and multiple endocrine neoplasia type 1 were cured at 5 years. A normal fasting serum gastrin or secretin stimulation value value immediately postoperatively provides important prognostic information.

Prognostic factors in patients with endocrine tumours of the duodenopancreatic area

BACKGROUND

The development of endocrine tumours of the duodenopancreatic area (ETDP) is thought to be slow, but their natural history is not well known. The aim of this study was to determine the factors that influence survival of patients with ETDP.

PATIENTS/METHODS

Eighty two patients with ETDP (44 non-functioning tumours, 23 gastrinomas, seven calcitonin-secreting tumours, four glucagonomas, three insulinomas, one somatostatinoma) followed from October 1991 to June 1997 were included in the study. The following factors were investigated: primary tumour size, hormonal clinical syndrome, liver metastases, lymph node metastases, extranodular/extrahepatic metastases, progression of liver metastases, local invasion, complete resection of the primary tumour, and degree of tumoral differentiation. The prognostic significance of these factors was investigated by uni- and multi-variate analysis.

RESULTS

Twenty eight patients (34%) died within a median of 17 months (range 1-110) from diagnosis. Liver metastases (p = 0.001), lymph node metastases (p = 0.001), progression of liver metastases (p < 0.00001), lack of complete resection of the primary tumour (p = 0.001), extranodular/extrahepatic metastases (p = 0.001), local invasion (p = 0.001), primary tumour size > or = 3 cm (p = 0.001), non-functioning tumours (p = 0.02), and poor tumoral differentiation (p = 0.006) were associated with an unfavourable outcome by univariate analysis. Multivariate analysis identified only liver metastases (risk ratio (RR) = 8.3; p < 0.0001), poor tumoral cell differentiation (RR = 8.1; p = 0.0001), and lack of complete resection of the primary tumour (RR = 4.8; p = 0.0007) as independent risk factors. Five year survival rates were 40 and 100% in patients with and without liver metastases, 85 and 42% in patients with and without complete resection of primary tumour, and 17 and 71% in patients with poor and good tumour cell differentiation respectively.

CONCLUSION

Liver metastases are a major prognostic factor in patients with ETDP. Progression of liver metastases is also an important factor which must be taken into account when deciding on the therapeutic approach. The only other independent prognostic factors are tumoral cell differentiation and complete resection of the primary tumour.

Enteropancreatic malignancy associated with multiple endocrine neoplasia type 1: risk factors and pathogenesis

BACKGROUND

Enteropancreatic malignancy is an important cause of morbidity and mortality associated with multiple endocrine neoplasia type 1 (MEN 1). However, the risk factors and mechanisms of the tumorigenesis of this malignancy are poorly understood.

METHODS

The authors conducted a retrospective study of factors associated with the development of malignant enteropancreatic tumor in 69 patients with MEN 1 belonging to a single family.

RESULTS

Metastatic enteropancreatic tumor and gastrinoma were identified in 20% and 36% of patients, respectively. Compared with MEN 1 patients who did not have an immediate family history of enteropancreatic malignancy, MEN 1 patients with a first-degree relative affected by enteropancreatic malignancy had an increased risk of developing disseminated tumor (odds ratio, 3.7; P < 0.05). In addition, hypergastrinemia and advanced age were both associated with a significant increase in the risk of enteropancreatic malignancy. Elevated serum glycoprotein alpha subunit levels were associated with enterochromaffin-like cell hyperplasia, gastric carcinoid formation, and disseminated enteropancreatic tumor in hypergastrinemic patients (P < 0.05).

CONCLUSIONS

Disease modifier factors act in concert with the MEN 1 gene to modulate the development of enteropancreatic neoplasia. It is possible to identify MEN 1 patients at high risk for developing aggressive enteropancreatic tumors. Heritable disease modifier factor(s) affecting enteropancreatic malignancy appear to reside at loci distinct from that of the MEN 1 gene.

Prospective study of somatostatin receptor scintigraphy and its effect on operative outcome in patients with Zollinger-Ellison syndrome

OBJECTIVE

To determine the relative abilities of somatostatin receptor scintigraphy (SRS) and conventional imaging studies (computed tomography, magnetic resonance imaging, ultrasound, angiography) to localize gastrinomas before surgery in patients with Zollinger-Ellison syndrome (ZES) subsequently found at surgery, and to determine the effect of SRS on the disease-free rate.

SUMMARY BACKGROUND DATA

Recent studies demonstrate that SRS is the most sensitive imaging modality for localizing neuroendocrine tumors such as gastrinomas. Because of conflicting results in small series, it is unclear in ZES whether SRS will alter the disease-free rate, which gastrinomas are not detected, what factors contribute to failure to detect a gastrinoma, or whether the SRS result should be used to determine operability in patients without hepatic metastases, as recently recommended by some investigators.

METHODS

Thirty-five consecutive patients with ZES undergoing 37 exploratory laparotomies for possible cure were prospectively studied. All had SRS and conventional imaging studies before surgery. Imaging results were determined by an independent investigator depending on surgical findings. All patients underwent an identical surgical protocol (palpation after an extensive Kocher maneuver, ultrasound during surgery, duodenal transillumination, and 3 cm duodenotomy) and postoperative assessment of disease status (fasting gastrin, secretin test imaging within 2 weeks, at 3 to 6 months, and yearly), as used in pre-SRS studies previously.

RESULTS

Gastrinomas were detected in all patients at each surgery. Seventy-four gastrinomas were found: 22 duodenal, 8 pancreatic, 3 primaries in other sites, and 41 lymph node metastases. The relative detection order on a per-patient or per-lesion basis was SRS > angiography, magnetic resonance imaging, computed tomography > ultrasound. On a per-lesion basis, SRS had greater sensitivity than all conventional studies combined. SRS missed one third of all lesions found at surgery. SRS detected 30% of gastrinomas < or =1.1 cm, 64% of those 1.1 to 2 cm, and 96% of those >2 cm and missed primarily small duodenal tumors. Tumor size correlated closely with SRS rate of detection. SRS did not increase the disease-free rate immediately after surgery or at 2 years mean follow-up.

CONCLUSIONS

SRS is the most sensitive preoperative imaging study for extrahepatic gastrinomas in patients with ZES and should replace conventional imaging studies as the preoperative study of choice. Negative results of SRS for localizing extrahepatic gastrinomas should not be used to decide operability, because a surgical procedure will detect 33% more gastrinomas than SRS. SRS does not increase the disease-free rate. In the future, more sensitive methods to detect small gastrinomas, especially in the duodenum and in periduodenal lymph nodes, or more extensive surgery will be needed to improve the postoperative disease-free rate in ZES.

Zollinger-Ellison syndrome. Improved treatment options for this complex disorder

Zollinger-Ellison syndrome is a rare disorder characterized by severe peptic ulcer disease, gastric acid hypersecretion, and non-beta islet cell tumors of the pancreas. Most gastrinomas are found within an anatomic area known as the gastrinoma triangle. However, they commonly occur in extrapancreatic sites in multiple endocrine neoplasia type 1 syndrome. In patients in whom Zollinger-Ellison syndrome is suspected, laboratory evidence of hypergastrinemia and hyperacidity establishes the diagnosis. Until the advent of proton pump inhibitors, total gastrectomy was the treatment of choice. Therapy with these agents (eg, omeprazole, lansoprazole) can prevent ulcer disease. However, surgical removal of gastrinomas offers a chance for cure and can improve longevity by preventing the malignant spread of the tumors.

Diagnostic and therapeutic criteria in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1

About 25% of patients with ZES have MEN-1. Except for diarrhoea, less frequent in patients with ZES MEN-1 than in sporadic ZES, and specific MEN-1-related signs, clinical characteristics are similar in both ZES types. Acid output and gastrin level are also similar whether in the basal state or after secretin. Primary hyperparathyroidism (pHPT) exists in the majority of ZES MEN-1 patients, 30% have pituitary adenoma (prolactinomas for half), 30% adrenal involvement, 25-30% have ECLomas: bronchial and thymic carcinoids have probably been underevaluated. Gastrinomas are multiple predominantly located in the duodenal wall, but also in the pancreas in association with clinically silent endocrine tumours. The spread of the disease metastases to the liver (LM), mediastinum, bones, is evaluated best by Octreoscan. Associated endoscopic ultrasonography evaluates the number, size and anatomical characteristics of gastrinomas. Patients without LM have an excellent prognosis. Surgery never cures ZES, but is necessary in cases of associated life-threatening conditions such as insulinoma. Although the size of the tumour, when located in the pancreas >3 cm, favours metachronous LM occurrence, surgery in our experience has not been able to prevent LM development.

Management of the Zollinger-Ellison syndrome in patients with multiple endocrine neoplasia type 1

Zollinger-Ellison syndrome (ZES) is the most common symptomatic pancreatic endocrine tumour in patients with MEN-1. Besides the treatment of the usual endocrinopathies seen in patients with MEN-1, the treatment of the ZES requires attention be paid to controlling the gastric acid hypersecretion, to dealing with the gastrinomas per se which are malignant in 18-60% of cases, and to the diagnosis and treatment of gastric carcinoid tumours, that are increasingly seen in these patients. In this article the current management of each of the areas is reviewed and what is known or uncertain discussed, based on our studies at the NIH and data from others. Data from 231 patients including 45 with MEN-1 and 186 without MEN-1 is contrasted in this report. Gastric acid hypersecretion has been controlled in all patients medically with MEN-1 and ZES at the NIH for up to 22 years. The current drugs of choice are H+-K+ ATPase inhibitors and twice a day dosing is recommended. Periods of parenteral drug therapy (surgery, etc.) and pregnancy require important modifications. The appropriate surgical therapy of the gastrinoma is controversial. Eighty per cent of patients have a duodenal gastrinoma and 20-30% have a pancreatic tumour. Recent studies suggest gastrinoma enucleation combined with duodenotomy rarely results in cure. Aggressive surgery (Whipple resection) can result in cure of gastrinoma but effect on survival is unclear. There are important differences in gastrinoma location, extent, and percentage with aggressive disease in patients with or without MEN-1, which are discussed. Confusion has occurred because of lack of information on the natural history of the gastrinoma compared to the other pancreatic endocrine tumours that occur in MEN-1 and survival data from patients with and without MEN-1 is contrasted. The occurrence of gastric carcinoids in patients with and without MEN-1 with ZES is contrasted and the areas of certainty and disagreement reviewed.

Effect of long-term gastric acid suppressive therapy on serum vitamin B12 levels in patients with Zollinger-Ellison syndrome

BACKGROUND AND AIMS

Long-term treatment with H(+)-K(+)-adenotriphosphatase (ATPase) inhibitors, such as omeprazole or lansoprazole, for severe gastroesophageal reflux disease is now widely used. Whether such treatment will result in vitamin B12 deficiency is controversial. We studied whether long-term treatment with omeprazole alters serum vitamin B12 levels in patients with Zollinger-Ellison syndrome.

METHODS

In 131 consecutive patients treated with either omeprazole (n = 111) or histamine H2-receptor antagonists (n = 20), serum vitamin B12 and folate levels and complete blood counts were determined after acid secretion had been controlled for at least 6 months. These studies were repeated yearly. Serum vitamin B12 and folate levels were correlated with the type of antisecretory drug and the extent of inhibition of acid secretion.

RESULTS

The mean duration of omeprazole treatment was 4.5 years, and for H2-receptor antagonists 10 years. Vitamin B12 levels, but not serum folate levels or any hematological parameter, were significantly (P = 0.03) lower in patients treated with omeprazole, especially those with omeprazole-induced sustained hyposecretion (P = 0.0014) or complete achlorhydria (P < 0.0001). In 68 patients with two determinations at least 5 years apart, vitamin B12 levels decreased significantly (30%; P = 0.001) only in patients rendered achlorhydric. The duration of omeprazole treatment was inversely correlated with vitamin B12 levels (P = 0.013), but not folate levels. Eight patients (6%) developed subnormal B12 levels during follow-up.

CONCLUSIONS

Long-term omeprazole treatment leads to significant decreases in serum vitamin B12 but not folate levels. These results suggest patients with Zollinger-Ellison syndrome treated with H(+)-K(+)-ATPase inhibitors should have serum vitamin B12 levels monitored. Furthermore, these results raise the possibility that other patients treated chronically with H(+)-K(+)-ATPase inhibitors may develop B12 deficiency.

Association of serum antibodies against p53 protein with poor survival in patients with Zollinger-Ellison syndrome

BACKGROUND & AIMS

Long-term survival of patients with Zollinger-Ellison syndrome (ZES) is largely determined by the presence or absence of liver metastases. However, because of the lack of precision of these criteria, development of further indicators is still required. Recent evidence showing that autoantibodies directed against the p53 protein could predict poor survival for some types of cancers prompted us to investigate the presence of such antibodies in sera from patients with ZES and their potential value as survival indicator.

METHODS

Anti-p53 antibodies were detected in the sera of 44 consecutive patients with ZES using both an enzyme-linked immunosorbent assay (ELISA) and Western blotting. The mean follow-up of these patients was 92 months.

RESULTS

Anti-p53 antibodies were detected in 7 of the patients with ZES (16%) by both ELISA and Western blotting. Univariate and multivariate analyses showed that the presence of anti-p53 antibodies (P = 0.0009 and P = 0.017, respectively) and liver metastases (P = 0.0009 and P = 0.012, respectively) was independently associated with shorter survival.

CONCLUSIONS

These results suggest that anti-p53 antibodies are an indicator of survival and could be used in combination with staging to determine which patients with ZES have poor prognoses and therefore require reinforced therapy.

Management of the Zollinger-Ellison syndrome in pregnancy

OBJECTIVE

There is almost no information on the management of patients with functional pancreatic endocrine tumors such as Zollinger-Ellison syndrome during pregnancy. The purpose of this study was to develop an approach for the management of such cases during pregnancy on the basis of experience with five recent cases.

STUDY DESIGN

Five women with Zollinger-Ellison syndrome who had seven pregnancies were the subject of this study. Each patient had an initial evaluation to confirm the diagnosis and to establish gastrinoma location and for the presence or absence of multiple endocrine neoplasia type I. In patients with Zollinger-Ellison syndrome diagnosed before conception, various medical or surgical treatments were established before conception and were used to control acid secretion throughout the pregnancy. The presence of upper gastrointestinal symptoms during pregnancy, maternal and fetal complications, gender, and weight of the infant were determined in all cases. Acid control was determined in four of the five patients during six pregnancies.

RESULTS

The interval between the onset of Zollinger-Ellison syndrome and the subsequent pregnancy varied from 0.6 to 9.9 years (mean 6.9 +/- 1.7 years). Zollinger-Ellison syndrome was unrecognized before pregnancy in two patients (40%); it was diagnosed between 0.2 and 2.4 years after the pregnancy. In three patients the time of diagnosis varied from 2.6 to 9 years before pregnancy. All patients had symptoms from gastric hypersecretion and elevated fasting serum gastrin levels that varied from 20% above normal to 37-fold above normal with mean of 2536 pg/ml (range 124 to 6970 pg/ml). Four of the five patients (80%) had positive secretin and calcium provocative tests. Two patients had multiple endocrine neoplasia type I. The five patients had seven pregnancies. Acid secretion was treated during pregnancy with antacids only (one patient), ranitidine alone (one patient), prior curative gastrinoma resection (one patient, two pregnancies), prior parietal cell vagotomy with incomplete tumor resection (one patient, two pregnancies), and prior parathyroidectomy and use of ranitidine in a patient with multiple endocrine neoplasia type I. In five pregnancies in three of the cases, no gastric antisecretory medications were needed during pregnancy. The mean acid secretion during pregnancy was 11.9 mEq/hr (range 0 to 42 mEq/hr). In the two cases with poor acid control and unrecognized Zollinger-Ellison syndrome mild fetal complications occurred.

CONCLUSIONS

It is possible for patients with Zollinger-Ellison syndrome to have pregnancies that are not complicated by gastric acid hypersecretion. If the Zollinger-Ellison syndrome is diagnosed before pregnancy, curative resection with parietal cell vagotomy may obviate the need for gastric antisecretory drugs. If metastases are present or the diagnosis of Zollinger-Ellison syndrome is made after conception, ranitidine in the lowest possible dose should be used to control acid secretion. If acid secretion in uncontrolled, the dose may be increased or omeprazole may be used.

Gastrointestinal endocrine tumours. Gastrinoma

Since the description of the Zollinger-Ellison syndrome in two patients in 1955, there have been significant advances in the understanding of its pathogenesis, natural history, relationship to multiple endocrine neoplasia type 1, diagnosis, methods of tumour localization and management. The main focus in treatment is now shifting from management of the gastric acid hypersecretory state which can now be controlled medically in almost every patient, to the management of the gastrinoma. Recent studies are beginning to provide insights into the natural history of gastrinomas, factors that are associated with invasiveness in some gastrinomas, defining the role of surgery in managing patients with different disease extents, or with MEN 1 and being able to provide insights into molecular abnormalities that may be important in their pathogenesis. In this article each of these advances is briefly reviewed with emphasis primarily on recent advances.

Is reoperation for gastrinoma excision indicated in Zollinger-Ellison syndrome?

BACKGROUND

Surgical excision of gastrinomas in patients with Zollinger-Ellison syndrome (ZES) decreases the incidence of hepatic metastases, but long-term biochemical cures are achieved in fewer than 30% of cases. A growing number of patients have persistent or recurrent disease after initial operation. The effect of reoperation in these patients has not been previously reported.

METHODS

From December 1982 to August 1995, 120 patients with ZES underwent operation for gastrinoma resection. Seventy-eight patients had recurrent or persistent ZES after operation; 17 patients underwent 18 reoperations. After initial operation all patients underwent yearly functional and imaging studies. If a tumor was unequivocally imaged, reexploration was done.

RESULTS

Five patients, all with sporadic disease, were disease free after operation, with a median follow-up of 28 months. Tumor was found in all 18 reoperations and resected in 17. In patients with continuing disease-free intervals, locations of gastrinomas included pancreatic head lymph nodes (three), liver metastasis (one), and pancreatic tail lymph node (one). There were no deaths in the cured group; two patients in the group with persistent disease have died (median follow-up, 34 months).

CONCLUSIONS

Reoperation for gastrinoma excision resulted in elimination of disease in 30% of patients and should be considered for patients with imageable disease.

Prolonged hypergastrinemia does not increase the frequency of colonic neoplasia in patients with Zollinger-Ellison syndrome

Whereas considerable experimental evidence suggests chronic hypergastrinemia can increase the occurrence of colonic neoplasia, the risks in man remain unclear. Zollinger-Ellison syndrome (ZES) is associated with marked plasma elevation of all forms of gastrin and, because of its prolonged course, has been shown to be an excellent model disease to study the effects of chronic hypergastrinemia in man. To determine whether profound chronic hypergastrinemia affects the occurrence of colonic dysplasia and neoplasia, 97 consecutive patients with ZES were studied. All patients underwent colonoscopic examination to the cecum, and the location, size, and type of polyps/tumors were determined. The patients had a mean fasting gastrin level 31 times above normal and a mean disease duration of 10 years; 17/97 (18%) had adenomatous polyps, 67/97 (69%) no adenomatous polyps, and 2/97 (2%) had colonoscopy and/or autopsy studies fo asymptomatic controls. Stratification by age or gender, presence of MEN-I, tumor extent, and duration of degree of hypergastrinemia did not increase prevalence. This study shows that despite prolonged, profound hypergastrinemia, no increased rate of colonic neoplasia (polyps or cancer) was noted. These data suggest that the development of hypergastrinemia secondary to continuous use of H+,K+-ATPase inhibitors for as long as 10 years is unlikely to cause an increased risk of developing colonic neoplasia in man.

A prospective study of the effectiveness of low dose omeprazole as initial therapy in Zollinger-Ellison syndrome

BACKGROUND

The proton pump inhibitors (omeprazole and lansoprazole) are the drugs of choice for the medical management of gastric acid hypersecretion in Zollinger-Ellison syndrome (ZES). These drugs are safe for long-term therapy but are acid-labile and high doses are expensive. The recommended starting dose of omeprazole is 60 mg/day. However, it has been shown in recent studies that the maintenance dose of omeprazole could be safely reduced to 20 mg once or twice a day in more than two-thirds of patients with ZES. The purpose of this study is to determine if an initial starting dose of omeprazole 20 mg/day is safe and effective in patients with ZES.

METHODS

Forty-nine consecutive patients with ZES being treated with ranitidine for at least 2 weeks were admitted to the NIH. Omeprazole 20 mg was started on day 1 of the admission and ranitidine discontinued 4 h after the first dose. Gastric acid output was measured for 1 h prior to the next omeprazole dose on day 2, then on day 3 if the value was > 10 mmol/h on the previous day. If acid-peptic symptoms developed or the gastric acid output remained > 10 mmol/h on day 3, the patient was considered to have failed omeprazole 20 mg/day initial therapy and the dose titrated daily to achieve adequate control of acid-peptic symptoms and gastric secretion.

RESULTS

In 33 of the 49 patients (68%) omeprazole 20 mg/day was successful as initial therapy. Sixteen patients (32%) failed this initial omeprazole dose (eight patients owing to persistent peptic symptoms and eight patients owing to inadequate acid control). The final daily omeprazole dose required in these patients was 40 mg in eight patients (16%), 60 mg in one patient (2%) and 80 mg in seven patients (14%). Basal acid output (BAO) was the only clinical or laboratory feature that was significantly different between the two groups in which low dose initial omeprazole therapy was or was not successful; all patients with basal acid output < 20 mmol/h had a successful outcome.

CONCLUSIONS

Because of the need to rapidly control gastric acid hypersecretion owing to the high risk of complications from peptic ulcer disease, patients with ZES should continue to be started on omeprazole 60 mg/day and the dose adjusted by acute titration methods as is currently recommended. After a maintenance dose is established, attempts should be undertaken to reduce the dose to 20 mg/ day once or twice a day. Only the minority of patients with ZES in whom basal acid output is known to be < 20 mmol/h (20% of patients) should be started on a low initial omeprazole dose.