The role of surgery in the Zollinger-Ellison syndrome

Zollinger-Ellison syndrome: past, present and future controversies

It is fitting that the Zollinger-Ellison syndrome (ZES) be included in the Lester Dragstedt Symposium because Dr. Dragstedt had a long-time interest in this disease, having been one of the five discussants of the original article and subsequently reporting with Dr. Oberhelman on nine cases. The approach to therapy of ZES has been controversial from the beginning, and a number of controversies remain. In this article, four different controversies are analyzed from the prospective of the past (Zollinger-Dragstedt era, 1955-1980), present and what may happen in the future in light of recent results. Specifically analyzed are: 1) the role of gastric surgery in the management; 2) whether gastrinoma removal without aggressive resection in patients with ZES without MEN-I is the preferred surgical therapy; 3) whether patients with MEN-I should undergo routine surgical exploration; and 4) whether most gastrinomas will be localized preoperatively. An analysis of recent advances suggests there may be marked changes in the future from our current and our past approaches.

Review article: the management of Zollinger-Ellison syndrome

Awareness of the sometimes subtle features of Zollinger-Ellison syndrome is important in order not to miss the diagnosis. Immediately after initial diagnostic tests, the patient should be given antisecretory medication, while tests for the type of Zollinger-Ellison syndrome and tumour extent can be delayed. Acid output should be decreased to < 10 mmol/h to control symptoms and prevent complications. Histamine H2-antagonists remain the best available intravenous therapy but omeprazole is the most effective long-term oral therapy and has proved to be safe in nearly 10 years of continuous use. The management of the gastrinoma has changed in recent years since the discovery that the majority of gastrinomas arise outside the pancreas. Exploratory surgery with tumour resection is the treatment of choice in sporadic Zollinger-Ellison syndrome but there are few indications for surgery in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type-1. None of the available therapies for metastatic gastrinoma is very effective.

Hepatic gastrinoma

A solitary hepatic tumor in a 50-year-old woman, which was observed as a hemangioma, ultimately was resected because it increased in size. The tumor volume doubling time was 28.8 months over the observed period of 30 months. The histologic diagnosis was carcinoid tumor. Immunohistochemical staining showed strong focal reactivity for gastrin and diffuse reactivity for pancreatic polypeptide, vasointestinal polypeptide, calcitonin, and parathormone. Preoperative gastric hyperacidity with diarrhea and a body weight loss of 7 kg, moderately controlled by cimetidine on admission, suggested high serum gastrin levels produced by the tumor. Her symptoms resolved after surgery, and she had a normal serum gastrin level with negative secretin stimulation test results. A review of six cases of hepatic gastrinoma suggests that surgical resection, if feasible, would be the treatment of choice.

Pathologic aspects of gastrinomas in patients with Zollinger-Ellison syndrome with and without multiple endocrine neoplasia type I

During the three decades since the recognition of the Zollinger-Ellison syndrome (ZES), major progress has been made in the diagnosis and treatment of this disease. However, the many failed operations in patients with ZES, the existence of primary lymph node gastrinomas, and the surgical approach of patients with ZES and multiple endocrine neoplasia type I (MEN-I) have remained controversial issues. In this review, our experience with the pathology of immunocytochemically identified gastrinomas in 44 patients with ZES is presented and related to the relevant literature. (1) Gastrinomas occur frequently in the duodenum (> 40%) and are commonly small (< 1 cm). They can therefore easily be missed at surgical exploration; lymph node metastases from such occult gastrinomas may be mistaken for primary tumors. (2) Most pancreatic gastrinomas reside in the head of the gland and have a diameter of 1 to 3 cm. (3) Gastrinomas associated with MEN-I are predominantly of duodenal origin and frequently multicentric; sporadic gastrinomas are single and more often pancreatic. Because MEN-I associated pancreatic tumors seldom contain gastrin, ZES in MEN-I patients is almost never cured by resection of the pancreatic tumors. (4) The metastatic potential of most small duodenal gastrinomas seems to be restricted to the regional lymph nodes.

Control of gastric acid hypersecretion in the management of patients with Zollinger-Ellison syndrome

During the last 5 years important advances have occurred in the control of gastric acid hypersecretion in Zollinger-Ellison syndrome (ZES). The increased availability of potent gastric acid antisecretory agents such as histamine H2-receptor antagonists and more recently the H+K(+)-ATPase inhibitors such as omeprazole and lansoprazole have made it possible to medically control acid secretion in all patients. Increased understanding of the variation in antisecretory drug dosage between individual patients has led to identification of criteria to ensure effective antisecretory control and to the recognition of subgroups of patients who require special monitoring. Effective regimens for parenteral antisecretory control during surgery have been established. The importance of parathyroidectomy in patients with multiple endocrine neoplasia type I with ZES and the possible usefulness of highly selective vagotomy have been investigated. We review here the new data that led to increased understanding in each of these areas from our studies and studies by others.

The Zollinger-Ellison syndrome. A collective surgical experience

A retrospective study of 90 surgically treated patients with the Zollinger-Ellison syndrome seen from 1958 through 1990 was performed. Fifteen patients had Zollinger-Ellison syndrome as a manifestation of multiple endocrine neoplasia type I. Preoperative tumor localization was positive in 46% of 54 patients studied. Gastrinomas were identified in 66% of patients, 38% of the tumors being malignant. Postoperative eugastrinemia was achieved in 11% of patients after a variety of surgical procedures. Exploratory laparotomy provides the only chance for cure and identifies the significant prognostic factors associated with long-term patient survival: small tumor size, extrapancreatic primary, and absence of tumor metastases.

Roux-limb motility after total gastrectomy and Roux-en-Y anastomosis in patients with Zollinger-Ellison syndrome

The Roux-en-Y syndrome was defined as chronic nausea, intermittent vomiting, and chronic abdominal pain worsened by eating in patients who have undergone a gastrojejunostomy Roux-en-Y reconstruction for peptic ulcer. When these patients fasted, the Roux limb showed striking abnormalities in motor function; when postprandial, they failed to convert to normal fed-state motor activity. In contrast, patients with Zollinger-Ellison syndrome do well after similar surgery; they can eat most foods and maintain their body weight. We studied the motility of the Roux limb and jejunum in six patients with Zollinger-Ellison after an esophagojejunostomy Roux-en-Y anastomosis. Roux-limb motor activity in these patients, as characterized by the migrating motor complex, was more frequent, well organized, and in synchrony with the remaining jejunum; most subjects also converted to the fed state after a liquid meal. We suggest that the enteric nervous system is intact and functions normally in patients who have had a Roux-en-Y reconstruction for ulcer disease secondary to Zollinger-Ellison, but not in patients with idiopathic peptic ulcer disease.

Benefit of resection of metastatic gastrinoma in multiple endocrine neoplasia type I

Although gastrinoma resection is generally advocated for patients with the sporadic form of nonmetastatic Zollinger-Ellison syndrome, there is controversy regarding the surgical management of the gastrinoma among patients with multiple endocrine neoplasia type I (MEN-I). Using strict criteria, to date no biochemical cures of the Zollinger-Ellison syndrome lasting greater than 5 months have been achieved by gastrinoma resection among patients with MEN-I. Whereas resections of hepatic metastases have been performed in patients with sporadic gastrinoma, none have been reported among patients with MEN-I. The current report describes a patient with MEN-I, closely followed up for 30 years, in whom enlargement of pancreatic gastrinoma and development of hepatic gastrinoma was observed to occur over 3 years. After preoperative localization, an 80% pancreatectomy and a left lateral segmentectomy of the liver were performed. Sixteen months after the operation, secretin and calcium provocative testing showed that the patient's fasting gastrin and stimulated plasma gastrin concentrations were normal; also, results of computerized tomographic angiography, selective abdominal angiography, and hepatic venous sampling for gastrin after intra-arterial secretin injection were negative for gastrinoma. By achieving a 16-month cure of gastrinoma, this case shows that an aggressive surgical approach can benefit certain patients with gastrinoma who have MEN-I even in the presence of hepatic metastases.

Curative resection in Zollinger-Ellison syndrome. Results of a 10-year prospective study

Since 1980, 73 patients with Zollinger-Ellison syndrome (ZES) without radiographic evidence of liver metastases were studied on a prospective protocol including medical management of gastric acid hypersecretion, extensive radiographic tumor localization, and exploratory surgery to find and resect gastrinoma for potential cure. Each patient had gastric acid hypersecretion effectively controlled with either H2-blockers or omeprazole. Patients were divided prospectively into two groups, with all patients undergoing the same preoperative localization studies and extensive laparotomy. In contrast to group 1 (1980-1986) (36 patients), group 2 (1987-Oct. 1990) (37 patients) also underwent additional procedures (transillumination and duodenotomy) at surgery to find duodenal gastrinomas. Preoperative imaging studies localized tumor in 38 (52%) patients, and portal venous sampling for gastrin determinations was positive in 49 (67%) patients. Gastrinomas were found and resected in 57 (78%) patients. Significantly more gastrinomas (92% of patients) were found in group 2 than in group 1 patients (64%) (p less than 0.01). This increase was due to increased numbers of duodenal gastrinomas in group 2 than in group 1 patients (43% versus 11%; p less than 0.01). The increased ability to find duodenal gastrinomas did not significantly improve the immediate disease-free rate, which was 58% for all patients. Duodenal primary gastrinomas were found to have a significantly greater incidence of metastases (55%) and a significantly shorter disease-free interval (12 months) than pancreatic gastrinomas (22% and 84 months, respectively) suggesting that duodenal gastrinomas may be more malignant and not more frequently curable than pancreatic gastrinomas. Operations were performed with no deaths and 11% morbidity rate. Long-term follow-up showed that 50% of patients initially rendered disease free would develop recurrent disease by 5 years. Survival was excellent for all patients, and none died of malignant spread of the tumor or uncontrolled peptic ulcer disease, with a mean follow-up of 5 years. This finding is in contrast to patients who presented with metastatic disease on imaging studies and had a 20% 5-year survival rate. This study suggests that all patients with localized sporadic ZES can have the gastric acid hypersecretion managed medically, that overall survival of these patients is excellent, most (78%) can have all gastrinoma found and resected, and some (30%) will be cured (long-term disease-free survival).

Pathobiology and management of hypergastrinemia and the Zollinger-Ellison syndrome

Gastrin is both stimulatory and trophic to the cells of the gastric fundus--parietal and peptic cells, and enterochromaffin-like (ECL) cells which are major intermediaries of the gastrin effect. Gastrin (from the antrum) and acid (from the fundus) represent the interactive positive and negative limbs of a feedback loop. The nature and extent of sub-loops, perhaps involving the vagus, acetylcholine, histamine, and other peptides and cell products are at present unclear or unknown. Loss of either gastrin or acid has predictable consequences. Absent acid, as in pernicious anemia or as a result of omeprazole, leads to hypergastrinemia. In rats, such hypergastrinemia (gastrin > 1,000 pg/ml) causes fundic ECL hyperplasia and, eventually, carcinoids; in humans with pernicious anemia, hypergastrinemia causes ECL-cell hyperplasia, which may progress to carcinoids that are reversible upon withdrawal of gastrin, illustrated by three cases described here. Loss of gastrin by antrectomy for duodenal ulcer leads to fundic involution and marked reduction in basal acid output, maximal acid output, and fundic histamine. An uncontrolled excess of gastrin, as from a gastrinoma outside the negative feedback loop, causes acid and pepsin hypersecretion with upper GI mucosal damage, the Zollinger-Ellison syndrome. This paper summarizes the abnormal regulation of gastrin and the biology, natural history, diagnosis, and management of ZE syndrome by medical and surgical means.

Surgical pathology of gastrinoma. Site, size, multicentricity, association with multiple endocrine neoplasia type 1, and malignancy

Specimens from the pancreas and duodenum of 26 patients with sporadic Zollinger-Ellison syndrome (ZES) and 18 patients with multiple endocrine neoplasia type 1 (MEN-1) and hypergastrinemia (17 with ZES) were screened immunocytochemically for gastrinomas. Location, size, multicentricity, and malignancy of the gastrinomas were evaluated. The MEN-1 patients had gastrinomas in the duodenum (nine of 18), pancreas (one of 18), and periduodenal lymph nodes (two of 18). No gastrinoma was identified in six patients. Most duodenal gastrinomas were multiple (five of nine) and smaller than 0.6 cm (six of nine). Lymph node metastases were present in eight of 12 patients. All 26 patients with sporadic ZES had a solitary gastrinoma; 14 were found in the pancreas and had a diameter greater than 2 cm. Ten patients had a duodenal gastrinoma, two with a diameter less than 0.6 cm. In two patients, only periduodenal "lymph node gastrinomas" were detected. Eighteen of the sporadic gastrinomas were malignant. These results suggest that duodenal location and multicentricity of gastrinomas are associated with the MEN-1 syndrome, and solitary gastrinomas, either in the pancreas or the duodenum, are predominantly seen in sporadic ZES.

Use of omeprazole in patients with Zollinger-Ellison syndrome

Omeprazole, a substituted benzimidazole, has been shown to be a potent inhibitor of gastric acid secretion in patients with Zollinger-Ellison syndrome (ZES). We review our experience, as well as the published data on 210 patients with ZES who have required omeprazole for control of gastric acid hypersecretion over the past seven years. The dose of omeprazole required in individual patients ranged from 10 to 180 mg/24 hr with 20-60% requiring a split dosage regimen. Omeprazole was effective in approximately 99% of the patients over a period ranging from 0.5 to 54 months. Twenty-four percent of patients required an increase in omeprazole dose, while 26% required a decrease in dose. Adverse effects attributable to omeprazole were reported in 2% of patients, and in all cases, they were mild (ie, rash, constipation, headache). There was no effect of omeprazole on serum gastrin concentration or on gastric endocrine cells in three studies. Although one patient with multiple endocrine neoplasia, type-I syndrome (MEN-I) in this series developed a gastric carcinoid while taking omeprazole, evidence is presented that suggests the presence of MEN-I per se may be important in determining the development of gastric carcinoid in patients with ZES. It is concluded that omeprazole is safe and effective in patients with ZES, and in these patients, it is the drug of choice for the management of gastric acid hypersecretion. However, yearly assessment is indicated to clearly evaluate the long-term risk of gastric carcinoid as well as therapy directed at the gastrinoma itself.

A case report of Zollinger Ellison syndrome and review of the literature

There is much controversy concerning the mode of therapy for patients in whom Zollinger-Ellison syndrome is strongly suspected but a tumor can not be located. We recently experienced a patient with Zollinger-Ellison syndrome presenting with melena in whom an attempt to stop the bleeding by H-2 antagonists failed and an emergency operation had to be carried out. At laparotomy, no tumor was found in the pancreas, duodenum or stomach wall and there was no specific swelling in any of the lymph nodes. A total gastrectomy was thus done with lymphadenectomy and a histopathological examination revealed two gastrinomas in the lymph nodes of the gastrinoma triangle. Postoperative secretin tests with 2 u/kg of secretin have been negative even 6.5 years later, and the patient is now well and working as a full time teacher. In this case, an emergency total gastrectomy was performed for uncontrolled bleeding, but we want to stress the importance of lymphadenectomy based on the findings of the frozen section and changes in gastrin levels.

Unresolved surgical issues in the management of patients with Zollinger-Ellison syndrome

In the last 10 years, there have been a number of major advances that have markedly changed the management of patients with Zollinger-Ellison syndrome. These advances have been described recently in a number of excellent reviews. After reading each of these reviews, including our own, one is left generally with the impression that most of the important problems and particularly those involving surgery in the treatment of this disease have been resolved; however, in considering the possible problems to address in protocols in the coming years in our patients with Zollinger-Ellison syndrome followed at the National Institutes of Health, it became apparent to us that not only will surgery play an increasingly important role in the management of this disease, but that there are a number of major questions in which various aspects involving surgery are not resolved. Furthermore, resolution of a number of these areas will have applicability to the surgical treatment of other islet cell tumors. The purpose of this article is to call attention to these questions with the hope that other investigators may also consider these and specifically attempt to address some of these issues in the surgical treatment of Zollinger-Ellison syndrome in prospective studies.

Detection of duodenal gastrinomas by operative endoscopic transillumination. A prospective study

The ability of operative endoscopic transillumination of the bowel wall to detect duodenal gastrinoma was evaluated prospectively in 26 patients with the Zollinger-Ellison syndrome. The results were assessed by exploratory laparotomy and compared with the results of other localization techniques. Twelve duodenal gastrinomas were resected from 10 patients. Operative endoscopic transillumination detected 10 of the 12 gastrinomas, a sensitivity of 83%, which was significantly greater (P less than 0.05) than that for either preoperative imaging (25%) or intraoperative ultrasonography and palpation (42%). The sensitivity of operative endoscopic transillumination was a result of the ability to detect focal areas that did not transilluminate on the serosal side of the duodenum, and not the mucosal appearances seen through the endoscope, which were not helpful. Operative endoscopic transillumination detected gastrinomas less than 1 cm in diameter throughout the duodenum. Of the patients in this study, 39% had duodenal gastrinomas, a greater frequency than previously reported. These results indicate that operative endoscopic transillumination is the most sensitive technique yet described for detecting duodenal gastrinomas and should be performed routinely in all patients with the Zollinger-Ellison syndrome who undergo exploratory laparotomy for cure.

Pancreatic tumors in childhood: analysis of 13 cases

Pancreatic tumors are rare in children. Over a 20-year period we have treated 13 children with pancreatic neoplasms. There were eight boys and five girls (age range, 4 months to 12 years). Seven tumors were benign, including five insulinomas, and two cystadenomas. Six lesions were malignant (rhabdomyosarcoma, 2; pancreatic carcinoma, 4). Children with insulinoma presented with hypoglycemia and irrational behavior. Three had abnormal insulin:glucose ratios ( greater than 1.0). The tumor was detected by computed tomography scan in three cases, at the time of surgery in one, and with intraoperative ultrasound in one. Surgical treatment included tumor enucleation in four cases and 80% pancreatectomy in one. Mucinous cystadenomas were observed in two patients, ages 4 months and 10 months. Tha latter infant underwent cyst excision alone, resulting in malignant recurrence at 18 months of age and death. The 4-month-old child had a distal pancreatectomy and is alive at 6 years. Two of the four children with pancreatic cancer had unresectable tumors at diagnosis, and were treated by biopsy (ductal adenocarcinoma), irradiation, and chemotherapy. Length of survival was 6 months and 9 months. Two others (ages 4 and 12 years) underwent 85% distal pancreatic resection for pancreatoblastoma and a pancreatoduodenectomy for papillary carcinoma, respectively. The latter is alive and tumor-free at 20 years of follow-up. The former underwent hepatic lobectomy for a 3.0 x 3.0 cm solitary liver metastases and is alive at 6 years with no evidence of disease. One child with rhabdomyosarcoma died of progressive disease, the other is alive with residual disease despite resection and chemotherapy. Most insulinomas can be treated by enucleation.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastrinoma

The Zollinger-Ellison syndrome with its main symptom of massive gastric hypersecretion presents problems with both the medical and surgical approaches to treatment. Successful medical treatment depends on a life-long commitment to rigid medication schedules requiring careful ongoing supervision and is subject to pitfalls of compliance, drug side effects, drug resistance, and complications of persistent tumor growth. Surgical therapy carries risks of operative mortality and complications. If a low operative mortality can be maintained and the nutritional results after total gastrectomy are good, then it is the authors' opinion that the permanent relief from dangers of hypersecretion afforded by total gastrectomy makes surgery a worthwhile approach. Based on our operative experience in 34 patients and interpretation of the experience of others, we believe that resection of all tumor that can be resected, combined with total gastrectomy, is safe and dependable. The results compare well with those of long-term medical management.

APUD update

Apudomas are a diffuse group of tumors that have interested surgeons for a long time. With recent developments in their radiological localization and pharmacological control, they are now treated in a truly multidisciplinary approach. In this chapter, recent developments in the radiological, surgical, and medical approaches to these tumors are reviewed. Emphasis is placed on how non-surgical developments have affected the surgical treatment of specific apudomas. Resulting changes in surgical philosophy are also reviewed.

Gastrinoma excision for cure. A prospective analysis

The role of surgery in the treatment of gastrinoma is unclear. The purpose of this study was to determine prospectively the surgical cure rate using a controlled clinical trial. Eleven patients who fit the entry criteria underwent abdominal exploration and attempted tumor resection for cure. A historical control group was used for comparison. Cure was defined as: (1) normal serum gastrin level, (2) no response to intravenous secretin, (3) no symptoms when antisecretory medications are stopped, and (4) no tumor recurrence on follow-up examination. Tumors found in both groups tended to be small (1.5 cm vs. 2.2 cm), multiple (71% vs. 40%), and in lymph nodes (70% vs. 70%). All tumors identified were located anatomically within the gastrinoma triangle. Tumors were found in 10 of 11 patients (91%) in the study group, and significantly more patients had their tumors excised for cure as compared to controls (82% vs. 27%, p less than 0.05). The current prospective cure rate for gastrinoma is higher than previously appreciated and tumors within lymph nodes do not preclude curative resection.

Current diagnosis and management of Zollinger-Ellison syndrome

The treatment of patients with Zollinger-Ellison syndrome (ZES) has undergone dramatic evolution during the past decade. Although initially regarded as an incurable tumor, resection of gastrinoma for potential cure has been reported in 30% to 40% of selected patients in recent series. Conversely, although definitive control of acid hypersecretion is achieved by total gastrectomy, histamine (H2)-receptor antagonists and the newly introduced agents omeprazole and somatostatin analogues allow effective medical therapy of gastric acid overproduction. Confirmation of the diagnosis is best achieved with the I.V. secretin stimulation test, and tumor localization techniques are mandatory to identify candidates for operative tumor resection. Intraoperative sonography and careful exploration are required for tumor removal; successful tumor resection is associated with prolonged survival. The majority of patients (60%) are still found to have malignant disease at the time of diagnosis, but 10-year overall survival commonly exceeds 40%. The presence of multiple endocrine neoplasia type I (MEN-I) is seen in 10% to 25% of patients; correction of hypercalcemia alone may have therapeutic benefit in some ZES patients, and while gastrinoma resection is rarely possible, MEN-I patients demonstrate prolonged survival. The choice of medical rather than surgical therapy for acid hypersecretion depends on the suitability of each patient for careful and repeated endoscopic and chemical studies, versus the likelihood of a successful postoperative outcome. Socioeconomic, geographic, and related medical factors in each case may dictate the form of long-term antisecretory therapy. Exploration for possible tumor resection is indicated for virtually all patients who have no documented metastatic disease.

Curative resection of multiple gastrinomas aided by selective arterial secretin injection test and intraoperative secretin test

Recently a number of surgeons have recommended radical resection of gastrinomas in Zollinger-Ellison syndrome (ZES). We have developed a useful technique for preoperative localization of gastrinomas--the selective arterial secretin injection test (SASI)--and we recommend an intraoperative secretin test (IOS) for deciding the radicality of resection of gastrinomas. Here the results of SASI and IOS tests in 11 patients with ZES are examined and compared with the results of other techniques. The SASI test localized gastrinomas in all of the patients, while the sensitivity of ultrasonography, computed tomography, arteriography, or portal venous blood samplings was between 1/11 and 5/11. On the basis of the results of the SASI test, radical resection of gastrinoma was performed in four patients (three pancreatoduodenectomies and one extirpation). After pancreatoduodenectomy, immunohistologic study of the specimen revealed multiple microgastrinomas and lymph node metastases in two patients and the coexistence of a microgastrinoma and a gastinoma in one patient. The IOS test was useful in the estimation of the advisability of radicality, and in two patients total gastrectomy was not performed because of the results of the IOS test. These four patients are well and have returned to work, and their serum gastrin levels are below 35 pg/mL. Thus we believe SASI and IOS tests are helpful for planning curative resection of gastrinomas.

Zollinger-Ellison Syndrome in the Intensive Care Setting

Management of patients with Zollinger-Ellison syn drome differs markedly from management of patients with idiopathic gastric acid hypersecretion or routine peptic ulcer disease. Because of the possible complica tions arising from gastric acid hypersecretion or from complications caused by the gastrinoma itself, patients with these disorders frequently present to critical care physicians. It is important that critical care physicians be familiar with the acute presentation of patients with Zollinger-Ellison syndrome as well as the appropriate treatment. We review the important points pertaining to the recognition and treatment of Zollinger-Ellison syn drome in the acute care setting.

Multiple endocrine syndrome type I. Clinical, laboratory findings, and management in five families

The clinical features of 20 patients from five families with multiple endocrine neoplasia syndrome type I (MEN-I) were studied. Nineteen patients (95%) had hyperparathyroidism. Five patients who had a diagnosis during surgery of adenoma and who had fewer than 3.5 glands removed had recurrence of hypercalcemia after surgery. Fourteen patients (70%) had pancreatic islet cell tumors. All had one or more elevated serum polypeptide hormones, and six had symptoms related to the hormones produced. Multiple pancreatic tumors were identified in the nine patients who underwent surgery. Three patients who died had a mean survival of 6.3 +/- 2.9 years. Eight patients had pituitary tumors; seven had macroadenomas. Of the eight patients with pituitary tumors, seven had high serum prolactin and responded to bromocriptine therapy, whereas the eighth patient had acromegaly treated with radiotherapy. It was concluded that hypercalcemia due to hyperparathyroidism in MEN-I syndrome patients should be managed by a resection of four glands and transplantation of one half gland into the forearm because none of the patients has shown evidence of a recurrence, and serum calcium levels have been normal. Pancreatic tumors, which are usually multiple, may be asymptomatic. Patients with these tumors usually have long survival rates, even with distant metastasis. Total pancreatectomy may be the method of choice, especially in patients with gastrinoma caused by the diffuse nature of the disease. Long-term follow-up is needed, however, with more patients. Pituitary tumors are primarily prolactin-producing tumors, and medical treatment is the method of choice.

Diagnosis and management of Zollinger-Ellison syndrome

With the recent widespread availability of gastrin radioimmunoassays, the development of increasingly effective medical therapy for gastric hypersecretion, and improved methods to localize gastrinomas in patients with Zollinger-Ellison syndrome, the diagnosis, treatment of the gastric acid hypersecretion, and approach to the tumor have changed significantly. Recent advances in each of these areas and the current management of a patient with Zollinger-Ellison syndrome are reviewed.

Gastrinoma. New medical and surgical approaches

The clinical presentation of gastrinoma has changed since the original description by Zollinger and Ellison in 1955. Tumors currently found are smaller, extrapancreatic or extraintestinal in location, and frequently occult within lymph nodes. The incidence of hepatic metastases on initial presentation has decreased. In addition, the clinical course of patients with tumor in lymph nodes is benign, suggesting that more patients than were previously thought are now candidates for cure. Improved knowledge of the anatomic location of gastrinomas has enhanced our ability to find and remove them at laparotomy. As a result of these factors, more patients are being cured than ever before, and in the future, cure rate may be even higher. On the basis of these recent advances, the optimal treatment of gastrinoma is surgical excision for cure.

Microgastrinomas of the duodenum. A cause of failed operations for the Zollinger-Ellison syndrome

Gastrinomas are now being detected at an earlier stage than was formerly the case. Furthermore, with the ability to control acid secretion, emphasis has been placed on identifying gastrinoma patients who are potentially curable by tumor resection rather than by palliative gastrectomy. Despites estimates suggesting that 20-40% of sporadic gastrinoma patients can be successfully resected for cure, as many as 40% of such patients have occult tumors that elude detection. In an effort to better localize gastrinomas, we have used percutaneous transhepatic venous (THVS) gastrin sampling over the past 10 years. From 1978 to 1988, THVS was used in 46 patients in whom there was no other evidence of metastatic gastrinoma by conventional studies. Gastrinomas were found at operation in all but one patient. The purpose of this report is to emphasize that occult tumors are most often found in the duodenal wall, and frequently they may be no greater than 2 mm in diameter. Five recent cases illustrate that these small tumors or microgastrinomas may be the sole source of hypergastrinemia and can be cured by local excision. These recent cases emphasize that microgastrinomas are not usually palpable through the duodenal wall. They may be detected only after duodenotomy and meticulous evaluation of the mucosa by eversion and direct palpation. Duodenotomy and intraluminal exploration should be considered an essential component of the operation for patients with extrapancreatic gastrinomas.

Gastrinomas. Clinical syndromes

During the last 17 years about 100 gastrinomas have been diagnosed in Denmark. With background of the Danish material and the literature the clinical features and pathology of gastrinoma are reviewed and its medical and surgical treatment discussed.

Effects of omeprazole on acid secretion and acid-related symptoms in patients with Zollinger-Ellison syndrome

In the Zollinger-Ellison syndrome, symptoms and complications are due to hypersecretion of acid, and the first therapeutic step is to suppress the acid secretion. Long-term treatment with histamine H2-receptor antagonists was compared with omeprazole treatment. A total of 30 consecutive ZES patients were treated continuously with H2-receptor antagonists. During long-term treatment, a marked tachyphylaxis was noted, more than 50% of the patients had periods of dyspepsia, recurrent ulcers were found in 10 patients and in 16 a decline in the action of the H2-receptor antagonist required a change to omeprazole after a median duration of 36 months. A total of 22 patients were treated with omeprazole. During long-term treatment, the dose could be reduced slightly. Inhibition of acid secretion was maintained in all cases, and none had dyspeptic symptoms. The median duration of treatment was 18 months, with a range of 1-120 months (H2-receptor antagonists) and 27 months with a range of 1-66 months (omeprazole). No side-effects were seen with omeprazole.

Surgical treatment of carcinoids and endocrine pancreatic tumours

The common association of neuroendocrine abdominal neoplasms, carcinoids and endocrine pancreatic tumours, with often severe endocrine symptoms has justified considerable efforts to improve treatment in these conditions. Surgery still constitutes the principle therapy for the majority of these tumours. However, the introduction of new means of medical treatment with cytostatic agents, or more recently interferon and a somatostatin analogue, seem to have impact on indications and the extent of surgery in malignant forms of these tumours. It is thus probable that a surgical tumour reduction will increase the possibilities to achieve positive effects of the medical treatment even in advanced malignancies. However, the existence of an alternative medical therapy has increased obligations that surgery should be performed without morbidity or mortality.

Outcome of lymph node involvement in patients with the Zollinger-Ellison syndrome

Prognosis of gastrinoma patients with metastases to lymph nodes only is uncertain, and the true nature of isolated nodal gastrinomas remains controversial. The purpose of this study was to determine the outcome of such patients and whether nodal gastrinomas may occur as primary lesions. Eleven patients with nodal involvement but without hepatic metastases are reported (mean follow-up of 129 months). Primary gastrinomas were located in the duodenum in seven (Group 1) and not identified in four (Group 2). In Group 1, five patients remained eugastrinemic after excision of all gross tumors and gastrectomy (n = 4) or pancreaticoduodenectomy (n = 1), one patient had residual disease and died of other causes (survival of 88 months), and one patient had MEA-I syndrome with multiple gastrinomas (follow-up of 126 months). In Group 2, three patients became eugastrinemic after nodal excision and total gastrectomy (mean follow-up of 212 months) and may represent primary nodal gastrinomas, and in one patient, liver metastases developed and the patient died. Four deaths occurred in a 27-year period, but only one was tumor-related. There was no significant difference in 20-year survival rates between the two groups (85% vs. 75%). It is concluded that 1) lymph node gastrinomas are usually metastatic from primary duodenal lesions, 2) although rare, nodal gastrinomas may occur as primary lesions, and 3) in the absence of hepatic metastases, lymph node gastrinomas, whether primary or metastatic, have a good prognosis and should not deter aggressive surgical treatment.

Diagnosis and treatment of Zollinger-Ellison syndrome

A diagnostic and therapeutic strategy for the management of patients with Zollinger-Ellison syndrome has been developed, based on the review of a large personal experience and the most recent literature. The mainstay of a modern ZES management is the eradication of tumoral processes whenever feasible. Diagnosis is centred upon gastric acid and gastrin secretion measurements both in basal conditions and on secretin stimulation. Recognition of other endocrine involvement and familial inheritance is of the utmost importance in distinguishing sporadic ZES patients from those who have the condition known as multiple endocrine neoplasia type I. Blood calcium and phosphorus levels, parathyroid hormone concentration, combined if necessary with urinary cyclic AMP excretion measurement, should be performed routinely once ZES diagnosis is established or highly suspected. Localization of the tumour is the next essential step, and this has been considerably facilitated by the recent development in imaging techniques: it involves computerized axial tomography and selective abdominal angiography, a combination of which allows tumour detection in 60-70% of sporadic gastrinoma patients, with a maximal sensitivity for well-developed hepatic metastases. In sporadic ZES exploratory laparotomy is legitimate when preoperative localization of the tumour has failed; this laparotomy will allow further detection and then eradication of gastrinomas in a significant number of patients. Control of gastric acid secretion is mandatory throughout the work-up period; modern antisecretory agents are efficacious in most cases; total gastrectomy, when control of acid hypersecretion has failed, is now exceptional. Eradication of the tumour should be attempted in cases of sporadic ZES in the absence of recognizable liver involvement. The chance of a definite cure provided by surgery when performed by an experienced surgeon varies from 20% to 60% in pancreatic and ectopic gastrinomas respectively. In ZES patients with MEN I, exploratory laparotomy is seldom indicated (other than for symptomatic associated endocrine secretion), as the chance of a definite cure by surgery is very rare. Parathyroid surgery is often indicated and should take place before any form of abdominal surgery. In cases of hepatic metastases, chemotherapy with streptozocin and fluorouracil is indicated and soon, perhaps, chemo-embolization.

Roux-Y stasis syndrome after gastrectomy

The aim of the present study was to determine which factors lead to upper gastrointestinal stasis after Roux-Y reconstruction. Among the 214 patients with Roux-Y reconstructions performed between 1961 and 1983, follow-up data were obtained for 187 (87 percent) after a mean of 6.2 years. Patients with vomiting of food but not bile, postprandial pain, and nausea were considered to have the Roux-Y stasis syndrome. The syndrome was found in 49 patients with gastrojejunostomy (30 percent of those at risk) but in only 2 patients with esophagojejunostomy (8 percent, p less than 0.05). The condition was more common in women than men (p less than 0.05), but it was equally common in patients with and without vagotomy. The mean length of the Roux-Y limb in patients with stasis was 41 cm, which was longer than the 36 cm in patients without stasis (p less than 0.001). When multiple logistic regression was used, the length of the Roux-Y limb emerged as the major risk factor (p less than 0.01). In conclusion, construction of Roux-Y limbs greater than about 40 cm in length may increase the incidence of the Roux-Y stasis syndrome.

Medical management of patients with Zollinger-Ellison syndrome who have had previous gastric surgery: a prospective study

We examined prospectively the criteria for medical management in 16 patients with Zollinger-Ellison syndrome who had had previous gastric surgery. Each patient received sufficient antisecretory medication to lower gastric acid output to less than 10 mEq/h during the last hour before the next dose of drug. The 7 patients with a vagotomy but no gastric resection were symptom-free and had no mucosal disease. Of 9 patients with a partial gastrectomy, 7 had mucosal disease, with or without symptoms, and 6 of the 7 patients had acid outputs of 5-10 mEq/h. In these patients, antisecretory medication was increased to reduce output to less than 5 mEq/h and symptoms and mucosal abnormalities resolved in each patient. Patients with Zollinger-Ellison syndrome and a vagotomy can be treated safely by reducing acid secretion to less than 10 mEq/h, but in patients with a partial gastrectomy, acid secretion must be reduced to less than 5 mEq/h, and adequacy of therapy must be checked further by endoscopy.

Management of Zollinger-Ellison syndrome with gastric antisecretory drugs

Antisecretory drugs are major tools for management of the Zollinger-Ellison syndrome (ZES). Cimetidine was first used as a successful substitute of total gastrectomy. However with high dosage side effects and an escape from control were observed. As a more potent H2-receptor antagonist ranitidine has obvious advantages and is still largely used. Famotidine is more promising with a longer duration of action and given at lower dosages. Omeprazole could be considered as a treatment of choice with specific action on the proton pump and no side effects. However, with this drug the danger of permanent hypergastrinaemia being associated with fundic carcinoïd induction should be appreciated. Long-acting somatostatin has theoretical advantages in reducing simultaneously acid and gastrin secretion with a potential antitrophic effect. Larger studies are needed to precisely assess the therapeutic potential of the last three drugs.

Zollinger-Ellison syndrome. Current concepts in diagnosis and management

The Zollinger-Ellison syndrome, although uncommon, is not rare, and most patients with the disorder present with clinical manifestations similar to those of patients with common peptic ulcer. Early studies emphasized death due to complications of massive gastric acid hypersecretion. However, with the availability of potent antisecretory agents to control acid secretion, death is now more frequently associated with the metastatic potential of slowly growing but malignant gastrinomas. Therefore, physicians should maintain a high degree of suspicion of the Zollinger-Ellison syndrome in assessing patients with either chronic peptic ulcer or unexplained secretory diarrhea. An evaluation aimed at early diagnosis of the Zollinger-Ellison syndrome should be instituted in such patients and should begin with a determination of the fasting serum gastrin level. At least 50 percent of patients with gastrinoma will have nondiagnostic serum gastrin concentrations and will therefore require provocative testing to establish the correct diagnosis. After the presence of the syndrome is established, patients should be treated with a potent antisecretory agent in doses sufficient to reduce basal acid output to less than 10 mmol in the hour preceding administration of the next dose. Although some patients may be maintained satisfactorily in this manner for extended periods, an approach aimed at tumor localization and extirpation is recommended in most patients. Preoperative evaluation should begin with CT scanning with intravenous contrast material. Selective angiography, and occasionally, portal venous sampling for gastrin, should be performed if the location and extent of tumor remain in question. If metastatic disease is demonstrated, or if MEN-I is present, surgery aimed at tumor resection, although it is occasionally effective, will probably be unsuccessful. Because of the considerable morbidity and mortality associated with pancreatoduodenectomy, it should not be performed for unresectable tumor in the head of the pancreas. In other patients with the Zollinger-Ellison syndrome, exploratory surgery should be performed; this should include a careful search for, and resection of, all pancreatic and extrapancreatic gastrinomas. With this approach, it is likely that at least 20 percent of all patients with the Zollinger-Ellison syndrome can be cured.

The use of high-resolution intraoperative ultrasound to localize gastrinomas: an initial report of a prospective study

We evaluated the use of high‐resolution, real‐time, B‐mode, intraoperative ultrasound (IOUS) compared to simple manual palpation to localize gastrinomas during laparotomies in 10 consecutive patients with Zollinger‐Ellison syndrome (ZES). All patients had clear biochemical evidence of ZES, and patients with metastatic gastrinoma identified preoperatively were excluded. Preoperative localization studies including ultrasound, computed tomography, and selective arteriography localized gastrinoma in 3 patients. Transhepatic portal venous sampling (PVS) for gastrin localized gastrin gradients to the pancreatic head region in 8 patients, and found no significant gastrin gradient in 2 patients. Gastrinomas were found at laparotomy and proven pathologically in 6 patients. Four patients had gastrinomas in the pancreatic head area as predicted by PVS; however, one patient had a tumor in the pancreatic tail and another in the jejunal wall. Palpation was the most sensitive intraoperative method to localize a gastrinoma (100% sensitivity). IOUS correctly imaged 3 gastrinomas (50% sensitivity). Palpation had 1 false‐positive finding (80% specificity) and IOUS had 2 false‐positive findings (60% specificity). All palpable masses that were also sonolucent on IOUS proved to be gastrinomas (3 patients). Thus, a combined positive finding raised the specificity and positive predictive value to 100%. We conclude that IOUS has utility in explorations for gastrinomas. Although not as sensitive or specific as palpation, IOUS can confirm, noninvasively, a suspicious palpable nodule. If IOUS fails to image a palpable nodule, our results suggest that the surgeon should still attempt to resect the nodule.

Total gastrectomy for benign disease

Among 37 patients who underwent total gastrectomy for nonmalignant disease, operative mortality was 4 per cent after 27 elective operations and 10 per cent after 10 emergency operations. Three other patients died 1 to 6 months after operation. Major postoperative complications occurred in 24 per cent. Long-term follow-up of 26 patients (81 per cent of survivors) after a mean +/- SEM of 8.4 +/- 1.1 years showed that 73 per cent of patients had no or only occasional, easily controlled, mild abdominal symptoms and good enough health to enable them to work or carry out normal activities for their age. The patients lost a mean of 15 per cent of their body weight, however, and about one third of them had weakness and diarrhea. A quarter of them had anemia despite iron and vitamin B12 therapy. Our conclusion was that total gastrectomy is a reasonable operation for benign diseases. Nonetheless, in view of the substantial postoperative mortality and morbidity, the operation should be used only when less extensive operations will not suffice.

Early surgical treatment of gastrinoma

Medical treatment of the Zollinger-Ellison syndrome has been generally accepted because of the proven efficacy of the histamine (H2)-receptor antagonists in achieving symptomatic relief, and because of early reports indicating that few, if any, gastrinomas were resectable for cure. Gastrin radioimmunoassay (RIA) has made earlier and more certain diagnosis possible, and therefore reevaluation of the surgical management of gastrinomas is necessary. Experience with 60 gastrinoma patients is reported. Comparison between the pregastrin RIA years (before 1970) and post-gastrin RIA years was made to determine whether there was evidence to support the continuation of medical treatment without attempts to resect the gastrinoma. Twenty-five cases were diagnosed in the pre-RIA years. Age at diagnosis ranged from 17 to 68 years (median, 45 years). All patients were operated on. Metastases were found in 56 percent. No tumor was identified in 8 percent. Tumor was resected for "cure" (normal fasting gastrin levels for two years postoperatively) in one patient. Seventeen patients have died, and tumor was the cause of death in 70 percent. The five-year survival rate was 44 percent; the 10-year survival rate was 40 percent. Thirty-five cases were diagnosed after 1970. Age at diagnosis ranged from 39 to 61 years (median, 46 years). Thirty patients were operated on. Metastases were identified in 23 percent and no tumor was found in 17 percent. Tumor was resected for "cure" in 30 percent of patients. Seven patients have died and tumor caused death in 42 percent. The five-year survival rate was 82 percent; the 10-year rate was 64 percent. Advances in diagnosis and surgical technique since 1970 have made early operative treatment applicable in patients with gastrinoma. Because death in most cases is caused by progression of the tumor, an aggressive surgical approach to resect the tumor is advised soon after the diagnosis of Zollinger-Ellison syndrome is established.

Localization and resection of gastrinomas in Zollinger-Ellison syndrome

From 1971-1986, 24 patients were diagnosed as having Zollinger-Ellison syndrome (ZES) and 22 patients had laparotomy. Of this group, gross tumor was identified in 15 of 22 patients. Ten of 15 patients had resection of their gastrinomas with the specific aim of curing the disease. This group had responded favorably to either cimetidine or ranitidine before operation. Preoperative transhepatic portal venous sampling (PVS) with gastrin determinations was performed in six patients; three patients had this procedure twice. The tumor was correctly localized by PVS in five of six patients. In four of six patients, the tumor was easily found at surgery. In two of six patients (33%) PVS was vital to intraoperative decisions. Criteria for biochemical cure are normal periodic fasting gastrin and secretin infusion tests. Of the 10 patients who had resection for potential cure, two patients failed within 48 hours of surgery on the basis of an elevated fasting serum gastrin level in one patient and a positive secretin infusion test in the other patient. Eight patients were considered cured with follow-up from 6 months through 15 years. Of the eight cured patients, the tumors were located as follows: four were extraintestinal and extrapancreatic, four were in the duodenal wall, one patient had a tumor located in the uncinate process of the pancreas, and one tumor was located in a lymph node along the lesser curve of the stomach. Two patients had mobilization of the pancreas and duodenum for a "blind" pancreatoduodenectomy based on preoperative PVS (2 procedures each patient). In one patient a 3-mm gastrinoma was enucleated from the posterior uncinate process. The second patient had pancreatoduodenectomy with findings of two duodenal wall gastrinomas. Both patients remained cured of ZES beyond 2 years. It is concluded that PVS does indeed locate some tumors before operation, even those not easily found at surgery. ZES can be cured by an aggressive approach combining preoperative tumor localization and tumor resection. Of the eight patients biochemically and perhaps biologically cured, follow-up was greater than four years in five patients, greater than two years in two patients, and beyond six months in one patient.

Zollinger-Ellison syndrome (gastrinoma). Current diagnosis and treatment

Zollinger-Ellison syndrome is being detected at an earlier stage through liberal use of serum gastrin testing and application of secretin provocative tests if needed. The peptic ulcer disease of patients with Zollinger-Ellison syndrome can usually be controlled by large doses of one of the new potent gastric acid inhibitors. A battery of preoperative localizing tests can then be applied to guide exploratory laparotomy in non-MEN I patients. The tumor should be resected if possible, and continued low gastrin levels after operation provide evidence of a complete resection. It is reasonable to perform a parietal cell vagotomy at celiotomy because it will facilitate control of acid secretion if tumor resection is not successful. The only need for total gastrectomy is in a few patients whose acid secretion cannot be controlled with H2 receptor antagonists or who cannot comply with medical therapy. When no tumor is found at celiotomy, the prognosis for long-term tumor-free survival is excellent. Unfortunately, if unresectable hepatic metastases are present at operation, the patient is likely to die from metastatic tumor.

Role of selective angiography in the management of patients with Zollinger-Ellison syndrome

To determine the ability of selective abdominal angiography to localize gastrinoma in patients with Zollinger-Ellison syndrome, selective angiography was performed in 70 consecutive patients and the results were assessed prospectively by either surgery, autopsy, or percutaneous biopsy. In addition, to define the role of angiography in the management of patients with gastrinoma, we compared the results of angiography with those of computed tomography (CT) scanning in 58 patients who underwent both tests. For gastrinoma in the liver, angiography had a specificity of 100% and a sensitivity of 86% with a positive predictive value of 100% and a negative predictive value of 94%. For extrahepatic gastrinoma, angiography had a specificity of 94% and a sensitivity of 68%, a positive predictive value of 97% and a negative predictive value of 53%. Comparison of CT scanning and angiography demonstrated that for hepatic tumor CT demonstrated 72% and angiography 89% of tumors, and the combination detected all tumors with no false-positive results. Outside the liver, CT scanning detected 57%, angiography 70%, and the combination 73% of tumors with a false-positive rate of 7%. These results indicate that if a CT scan is performed first, then the addition of selective angiography will detect a further 28% of hepatic tumors and a further 16% of extrahepatic tumors, but that 24% of extrahepatic tumors will still be missed. Angiography is a useful adjunct to CT particularly in patients in whom surgery is contemplated.

Prospective study of the ability of computed axial tomography to localize gastrinomas in patients with Zollinger-Ellison syndrome

The ability of routine computed tomography (CT) performed with oral and intravenous contrast to localize gastrinomas in 61 consecutive patients with Zollinger-Ellison syndrome was evaluated prospectively. The results of CT scanning were subsequently evaluated in all patients by either surgery, autopsy, or percutaneous biopsy. Thirteen of 14 patients with CT scans positive for hepatic metastases and 5 of 13 patients with CT scans negative for hepatic metastases were found to have gastrinoma in the liver. For gastrinoma metastatic to the liver, CT scanning had a specificity of 98%, a sensitivity of 72%, a positive predictive value of 93%, and a negative predictive value of 90%. Twenty-two of 23 patients with positive extrahepatic CT scans and 15 of 33 patients with negative extrahepatic CT scans were found to have extrahepatic gastrinomas. For extrahepatic gastrinoma, CT scanning had a specificity of 95%, a sensitivity of 59%, a positive predictive value of 96%, and a negative predictive value of 54%. The ability of CT scan to detect gastrinomas both in the liver and extrahepatically was directly related to tumor size, detecting 0% of tumors less than 1 cm and 83%-95% of tumors greater than 3 cm. The location of the extrahepatic gastrinoma was also an important determinant in that approximately 80% of pancreatic gastrinomas but only 35% of extrapancreatic gastrinomas were detected. The present results indicate that because of its convenience and accuracy, CT scanning with oral and intravenous contrast material should be the initial procedure to evaluate the extent of gastrinoma. A positive CT scan is almost always correct; therefore, a CT scan detecting metastatic gastrinoma to the liver would avoid unnecessary surgery and, if positive for extrahepatic gastrinoma, would assist the surgeon in finding the gastrinoma. A negative CT is less reliable; therefore, patients should undergo other localizing studies before exploratory laparotomy.

Usefulness of selective arterial secretin injection test for localization of gastrinoma in the Zollinger-Ellison syndrome

Secretin was injected into a feeding or nonfeeding artery of a gastrinoma and blood samples were taken from the hepatic vein (HV) or a peripheral artery (PA) to measure the changes of serum immunoreactive gastrin concentration (IRG). The IRG in the HV rose within 40 seconds and in the PA rose within 60 seconds after the injection of secretin into a feeding artery, but not after secretin was injected into a nonfeeder. These results indicated that secretin directly stimulates a gastrinoma to release gastrin in vivo. The selective arterial secretin injection test (SASI test) was applied in three patients in whom gastrinomas could not be located by computed tomography, ultrasonography, or arteriography, and functioning gastrinomas were located in all three patients. In one patient, malignant gastrinomas in the head of the pancreas and in the duodenum could be resected radically with the help of this test.

Neuroendocrine tumors. A European view

A center in Belfast, Northern Ireland, has established a register for tumors of the gastroenteropancreatic endocrine system. Carcinoid tumors occur most frequently. Of the non-carcinoid tumors, insulinomas, gastrinomas, and unknown types have the highest incidence, with other types being extremely rare. The potentially remediable nature of the tumors is stressed, and frequently a good quality of life can be experienced even in the presence of metastatic disease. The syndromes are probably underdiagnosed as they present with clinical features for which there are more common explanations, and appropriate diagnostic methods are therefore not used. The management of the syndromes is reviewed with particular emphasis on the treatment of patients with inoperable disease. Histamine (H2)-receptor antagonist therapy has made an impact in Zollinger-Ellison syndrome, and streptozotocin and somatostatin analogues can control tumor growth and endocrine syndromes, respectively.

Selective venous sampling for gastrin to localize gastrinomas. A prospective assessment

In 27 consecutive patients with Zollinger-Ellison syndrome, we prospectively evaluated the ability of selective venous sampling for gastrin to localize gastrinomas, then compared the results with those from imaging studies and with findings at surgery. All patients had a gastrin gradient, but in only 20 patients was it significant. Neither the magnitude of the gastrin gradient nor its presence or absence correlated with the frequency with which gastrinoma was found at surgery. A gastrinoma was found at surgery in 15 patients, of whom 12 had positive imaging studies, 11 had a significant gastrin gradient, 14 had both tests positive, and 1 had both tests negative. A gastrinoma was not found at surgery in 12 patients, of whom 8 had a significant gradient and none had a positive imaging study. Gastrin sampling has equal sensitivity with imaging studies in localizing gastrinoma, but imaging studies have higher positive and negative predictive values and higher specificity. Thus, selective venous sampling for gastrin is much less useful in localizing gastrinoma than has been suggested and should not be routinely done preoperatively in patients with Zollinger-Ellison syndrome.

Prospective study of gastrinoma localization and resection in patients with Zollinger-Ellison syndrome

In 1982, a prospective study was initiated of 52 consecutive patients with proven Zollinger-Ellison syndrome (ZES), involving surgical exploration with the goal of removing the gastrinoma after an extensive protocol to localize the tumor. Each patient underwent ultrasound, computed tomography (CT) with oral/intravenous (IV) contrast, and selective arteriography. Eighteen patients had metastatic disease identified by imaging studies and confirmed by percutaneous biopsies, and two patients had multiple endocrine neoplasia type I (MEN-I) with negative imaging studies; therefore, these 20 patients did not undergo laparotomy. Each of the remaining 32 patients (3 with MEN-I and positive imaging studies) underwent laparotomy, and gastrinomas were removed in 20 patients. Preoperative ultrasound localized tumors in 20% of patients, CT in 40%, arteriography in 60%, and any of the modalities in 70% of patients. Infusion CT and arteriography were 100% specific. In 18 patients with either negative imaging (17) or false-positive imaging (1 ultrasound), gastrinomas were found and removed in six patients (33%). Twenty-four gastrinomas were found in 20 patients at laparotomy: eight in lymph nodes around the pancreatic head, four in the pancreatic head, one in the pancreatic body, three in the pancreatic tail, three in the pyloric channel, one in the duodenal wall, two in the jejunum at the ligament of Treitz, one in the ovary, and multiple liver metastases in one patient. If one excludes patients with MEN-I or liver metastatic disease, 12/28 (43%) of patients were biochemically "cured" immediately after operation. This result decreased to 7/23 (30%) with greater than 6 months follow-up. No patients with gastrinomas resected have developed recurrent gastrinoma on follow-up imaging studies (longest follow-up: 4 years). This study indicates that 95% of metastatic gastrinoma can be diagnosed before operation and that, by a combination of careful imaging studies and thorough exploration at surgery, 30% of patients with gastrinomas may be curable.