Localization and resection of gastrinomas in Zollinger-Ellison syndrome

How to treat gastrinomas in patients with multiple endocrine neoplasia type1: surgery or long-term proton pump inhibitors?

In patients with multiple endocrine neoplasia type 1 syndrome (MEN 1) and Zollinger-Ellison syndrome (ZES), gastrinomas arise from the duodenum, about 60% are multiple, and about 15% of patients have coexisting pancreatic gastrinomas, which can be localized by the selective arterial secretagogue injection test (SASI test). The guidelines (GLs) by the Japanese Neuroendocrine Tumor Society (JNETS) recommend surgical resection for functioning duodenopancreatic neuroendocrine tumors (NETs), including gastrinomas, in patients with MEN1 (Grade A, 100% agreement among members). Conversely, the GLs of the National Comprehensive Cancer Network (NCCN) in the USA recommend observation and treatment with proton pump inhibitors (PPIs) or exploratory surgery for occult gastrinomas. An international Consensus Statement (ICS) from the European Union (EU) also does not recommend resection of gastrinomas in patients with MEN1, despite some surgeons having reported surgery being curative for gastrinomas in MEN1 patients. In this review, we discuss the serious side effects and tumorigenic effects of the prolonged use of PPIs and the safety and curability of surgery, supported by our results of curative surgery for gastrinomas in 20 patients with MEN1 over 30 years. We conclude that surgery should be the first-line treatment for gastrinomas in MEN1 patients.

Broad-Spectrum Antivirals Derived from Natural Products

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Successful Lifetime/Long-Term Medical Treatment of Acid Hypersecretion in Zollinger-Ellison Syndrome (ZES): Myth or Fact? Insights from an Analysis of Results of NIH Long-Term Prospective Studies of ZES

Analysis of the efficacy/pharmacology of long-term/lifetime medical treatment of acid hypersecretion in a large cohort of ZES patients in a prospective study. This study includes the results from all 303 patients with established ZES who were prospectively followed and received acid antisecretory treatment with either H2Rs or PPIs, with antisecretory doses individually titrated by the results of regular gastric acid testing. The study includes patients treated for short-term periods (<5 yrs), patients treated long-term (>5 yrs), and patients with lifetime treatment (30%) followed for up to 48 years (mean 14 yrs). Long-term/lifelong acid antisecretory treatment with H2Rs/PPIs can be successfully carried out in all patients with both uncomplicated and complicated ZES (i.e., with MEN1/ZES, previous Billroth 2, severe GERD). This is only possible if drug doses are individually set by assessing acid secretory control to establish proven criteria, with regular reassessments and readjustments. Frequent dose changes both upward and downward are needed, as well as regulation of the dosing frequency, and there is a primary reliance on the use of PPIs. Prognostic factors predicting patients with PPI dose changes are identified, which need to be studied prospectively to develop a useful predictive algorithm that could be clinically useful for tailored long-term/lifetime therapy in these patients.

A primary hepatic gastrinoma accompanied by hyperplasia of multi-nodular Brunner's glands

BACKGROUND

Primary hepatic gastrinoma causing severe ulcerogenic syndrome is extremely rare. Herein, we report a case of primary hepatic gastrinoma accompanied by hyperplasia of multi-nodular Brunner's glands in a patient who instead, preoperatively, was suspected of having multiple duodenal gastrinomas and hepatic metastasis.

CASE PRESENTATION

A 57-year-old woman consulted a clinic complaining of melena, intermittent abdominal pain, diarrhea, and vomiting which had persisted for about 3 years. Six months before her presentation, she underwent segmental resection of the jejunum for acute peritonitis due to the spontaneous jejunal perforation. A blood test revealed that her serum immunoreactive gastrin (IRG) level was 12,037 pg/mL. Subsequently, she was transferred to our hospital. On computed tomography (CT), a hypervascular tumor of 23 mm in the segment 5 (S5) region of the liver was visualized. A selective arterial secretagogue injection test (SASI test) was performed twice. The first SASI test revealed that the hepatic tumor was a gastrinoma, and there was no gastrinoma in the duodeno-pancreatic region. Additionally, somatostatin receptor scintigraphy only visualized the tumor in the liver. However, the second SASI test, which was performed during the administration of a proton pump inhibitor and a somatostatin analog (octreotide acetate), revealed that there may have been gastrinomas existing not only in the liver but also in the upper part of the duodenum or the head of the pancreas. Duodenal endoscopy revealed multiple submucosal tumors in the first and the second portion of the duodenum, although a pathological examination of biopsied specimens obtained from the duodenal lesions was negative for malignant cells. Multiple endocrine neoplasia type 1 (MEN1) was excluded from her family history, and serum levels of both intact parathyroid hormone (iPTH) and calcium were within normal ranges. An anterior segmentectomy of the liver and pancreas-preserving total duodenectomy were performed on September 9, 2013. Postoperatively, her serum immunoreactive gastrin level decreased to less than 50 pg/mL. Pathological study of the resected specimens revealed a gastrinoma in the liver, but no gastrinoma in the duodenum. Interestingly, the duodenal submucosal tumor-like lesions were hyperplastic Brunner's glands. Postoperatively, she has been well without recurrence of hypergastrinemia for 4 years.

CONCLUSION

We report a case of primary hepatic gastrinoma in a patient who has been cured for 4 years postoperatively. The diagnosis was somewhat difficult due to the coexisting, multiple hyperplastic Brunner's glands of the duodenum mimicking the submucosal neuroendocrine tumors, which might have developed due to long-term hypergastrinemia.

Primary lymph node gastrinoma. A diagnosis of exclusion. A case for duodenotomy in the setting of a negative imaging for primary tumor: A case report and review of the literature

INTRODUCTION

Zollinger–Ellison syndrome (ZES) is caused by uninhibited secretion of gastrin from a gastrinoma. Gastrinomas most commonly arise within the wall of the duodenum followed by the pancreas. Primary lymph node gastrinomas have also been reported in the literature. This is a case of ZES where preoperative localization revealed a gastrinoma in a solitary portacaval lymph node, presumed to be a primary lymph node gastrinoma.

PRESENTATION OF CASE

The patient is a 57 year old female diagnosed with ZES, suspected of having a primary lymph node gastrinoma. The patient underwent an exploratory laparotomy and excision of a portacaval lymph node with a frozen section which was positive for gastrinoma. Intraoperative sonography of the pancreas, upper endoscopy with transillumination of the duodenum, and a duodenotomy with bimanual examination of the duodenal wall were also performed. The patient was found to have a 4 mm duodenal mass near the pylorus, which was excised.

DISCUSSION

Pathology showed that the duodenal mass was primary gastrinoma. Serum gastrin levels taken four months postoperatively were normal and the repeat octreotide scan did not show any evidence of recurrence.

CONCLUSION

Primary lymph node gastrinoma is a diagnosis of exclusion. The duodenum and pancreas must be fully explored to rule out a primary gastrinoma that may be occult.

Lymph nodes metastasis and recurrences justify an aggressive treatment of gastrinoma

In the current study, short- and long-term outcomes after aggressive surgical treatment for gastrinoma were evaluated. From August 1990 to August 2009, 20 patients diagnosed with Zollinger Ellison syndrome were reviewed. Eleven pancreaticoduodenectomies, three total pancreatectomies, four lymph node dissections, four enucleations and two palliative procedures were performed. Four (27.8 %) patients had disease associated with MEN1 syndrome, 13 (72.2 %) had sporadic gastrinomas (SG) and 3 had disease of unknown primary origin. No in-hospital mortality was observed. After radical resection, lymph node metastasis was present in 82 % of the cases. Eight percent of patients who underwent radical resection developed recurrence compared with 100 % of those who underwent enucleoresection (p = 0.03). Average time to recurrence in patients with sporadic gastrinoma was 66.7 months (confidence interval (CI) 62.9-70.5) in those treated with enucloeresection compared to 181.1 months (CI 124.3-237.8) in the radical resection group (p = 0.007). One recurrence was observed in the MEN1 group. Based on post-operative mortality, recurrence and lymph node metastasis, our data suggest that patients with gastrinoma should undergo abdominal exploration with aggressive resection of the primary tumour and regional lymph nodes in place of conservative treatment.

Reoperative surgery for the Zollinger-Ellison syndrome

It is clear that a properly performed initial operation is the key to success in the management of a patient with ZES. However, reoperation is frequently a consideration in the management of patients with ZES because high rates of persistent and recurrent disease are manifest even with modern imaging and surgical approaches. In carefully selected patients, reoperation can result in durable biochemical cure and improved survival and should be considered. A thorough knowledge of the natural history of the sporadic form of ZES and ZES in the context of MEN-1, patterns of presentation, and sites of metastases are necessary to achieve the best outcome in patients with this unusual disease.

Long-Term Results of a Selective Surgical Approach to Management of Zollinger-Ellison Syndrome in Patients with MEN-1

The role of operation in patients with Multiple Endocrine Neoplasia Type 1 (MEN-1) and Zollinger-Ellison Syndrome (ZES) is controversial. Our institutional bias for this disease has, in general, been towards aggressive imaging and operative removal of localized gastrinomas. Few studies have reported long-term outcomes in patients with MEN-1 and ZES. A single institution retrospective review of all patients with MEN-1 and ZES from 1970 to present was performed. Twelve patients were identified (median age = 37 years at diagnosis). The median follow-up was 18 years from diagnosis of ZES. Common symptoms associated with gastrinoma in these patients were diarrhea (n = 6), abdominal pain (n = 4), and nausea/vomiting (n = 4). Most commonly identified sites of gastrinoma were: pancreas (n = 10), duodenum (n = 4), lymph nodes (n = 3), and liver (n = 1). Fifteen celiotomies were performed in total (median = 1; range 0-3). Operative procedures performed included: distal pancreatectomy (n = 4), acid reducing procedure (n = 4), enucleation of pancreatic gastrinoma (n = 3), duodenal resection (n = 3), pancreaticoduodenectomy (n = 1), and other (n = 7). One patient had a transient biochemical cure after operation lasting 3 years. Only one patient in this series had documented liver metastases of gastrinoma and no patients expired of metastatic gastrinoma. There was one postoperative patient death, secondary to respiratory arrest thought to be a result of aspiration or pulmonary embolus. Three patients died of nondisease related causes, and seven patients were alive at the time of last follow-up. Operations rarely result in biochemical cures in patients with MEN-1 and ZES. In our experience, resection of localized gastrinomas often did not require extended surgical resection and were associated with excellent long-term outcomes.

Reoperative surgery in sporadic Zollinger-Ellison Syndrome: longterm results

BACKGROUND

Most patients with Zollinger-Ellison Syndrome (ZES), even those in whom gastrinoma is found and resected at initial operation, will suffer from persistent or recurrent disease in longterm followup. There is currently no consensus about managing patients with recurrent or persistent ZES. Our unit has historically maintained an aggressive approach toward monitoring and reoperation for patients with sporadic ZES.

STUDY DESIGN

We performed a review of a consecutive series of patients evaluated and managed at our institution between 1970 and 2007 for ZES. "Biochemical cure" was defined as normal serum gastrin assays and negative imaging studies. Reoperations were performed for elevations in serum gastrin assays and positive findings on imaging studies.

RESULTS

Fifty-two patients with sporadic ZES were analyzed. Median followup was 14 years. Among patients with sporadic ZES, 37 patients underwent operative management. The most common operations were resection of duodenal gastrinoma (n=8) and total gastrectomy (n=7). Nine patients underwent 15 reoperations for recurrent or persistent disease. "Biochemical cure" was obtained in four patients (44%) undergoing reoperation for ZES. Three of these patients remained without evidence of recurrence at 4, 9, and 12 years after their curative re-resection. Only one of nine patients who underwent reoperation died of metastatic gastrinoma.

CONCLUSIONS

Primary and reoperative surgery in patients with sporadic ZES results in a significant rate of "biochemical cure." In selected patients with recurrent or persistent disease, reoperation for resection of gastrinoma is associated with excellent longterm survival and is warranted.

Serum gastrin in Zollinger-Ellison syndrome: I. Prospective study of fasting serum gastrin in 309 patients from the National Institutes of Health and comparison with 2229 cases from the literature

The assessment of fasting serum gastrin (FSG) is essential for the diagnosis and management of patients with the Zollinger-Ellison syndrome (ZES). Although many studies have analyzed FSG levels in patients with gastrinoma, limited information has resulted from these studies because of their small size, different methodologies, and lack of correlations of FSG levels with clinical, laboratory, or tumor features in ZES patients. To address this issue, we report the results of a prospective National Institutes of Health (NIH) study of 309 patients with ZES and compare our results with those of 2229 ZES patients in 513 small series and case reports in the literature. In the NIH and literature ZES patients, normal FSG values were uncommon (0.3%-3%), as were very high FSG levels >100-fold normal (4.9%-9%). Two-thirds of gastrinoma patients had FSG values <10-fold normal that overlap with gastrin levels seen in more common conditions, like Helicobacter pylori infection or antral G-cell hyperplasia/hyperfunction. In these patients, FSG levels are not diagnostic of ZES, and gastrin provocative tests are needed to establish the diagnosis. Most clinical variables (multiple endocrine neoplasia type 1 status, presence or absence of the most common symptoms, prior medical treatment) are not correlated with FSG levels, while a good correlation of FSG values was found with other clinical features (prior gastric surgery, diarrhea, duration from onset to diagnosis). Increasing basal acid output, but not maximal acid output correlated closely with increasing FSG. Numerous tumoral features correlated with the magnitude of FSG in our study, including tumor location (pancreatic > duodenal), primary size (larger > smaller) and extent (liver metastases > local disease). In conclusion, this detailed analysis of FSG in a large number of patients with ZES allowed us to identify important clinical guidelines that should contribute to improved diagnosis and management of patients with ZES.

Zollinger-Ellison phenotype in the absence of hypergastrinemia and islet-cell tumor

Patients with the Zollinger-Ellison syndrome are characterized by islet-cell tumors, striking gastric acid hypersecretion, and peptic ulcer disease. They often experience severe abdominal pain, diarrhea, and gastrointestinal bleeding with potentially life-threatening consequences. It is a rare syndrome caused by non-beta cell islet-cell tumors (gastrinomas) located in or in proximity to the pancreas. These tumors freely secrete gastrin, a peptide hormone that serves as a powerful stimulant of gastric acid secretion. Exuberant secretion of gastrin from the gastrinomas produces severe gastric acid hypersecretion that often leads to impressive peptic ulcer disease and the constellation of symptoms listed above. We describe a patient presenting with clinical manifestations characteristic of the ZES with strikingly elevated gastric acid secretion,multiple ulcers in the first and second portions of the duodenum and diarrhea, but in absence of islet-cell tumor and/or hypergastrinemia.

Resolved and unresolved controversies in the surgical management of patients with Zollinger-Ellison syndrome

OBJECTIVE

Highlight unresolved controversies in the management of Zollinger-Ellison syndrome (ZES).

SUMMARY BACKGROUND DATA

Recent studies have resolved some of the previous controversies including the surgical cure rate in patients with and without Multiple Endocrine Neoplasia-type1 (MEN1), the biological behavior of duodenal and pancreatic gastrinomas, role of imaging studies to localize tumor, and gastrectomy to manage acid output.

METHODS

Review of the literature based on computer searches in Index Medicus, Pubmed and Ovid.

RESULTS

Current controversies as identified in the literature include the role of endoscopic ultrasound (EUS), surgery in ZES patients with MEN1, pancreaticoduodenectomy (Whipple procedure), lymph node primary gastrinoma, parietal cell vagotomy, reoperation and surgery for metastatic tumor, and the use of minimally invasive surgical techniques to localize and remove gastrinoma.

CONCLUSIONS

It is hoped that future studies will focus on these issues to improve the surgical management of ZES patients.

A prospective analysis of the frequency, location, and curability of ectopic (nonpancreaticoduodenal, nonnodal) gastrinoma

BACKGROUND

Extrapancreatic, extraduodenal and extralymphatic (ectopic) gastrinomas have been reported only rarely. The frequency, locations, and surgical outcome of these lesions are unknown.

METHODS

From 1982 to 1997, 215 patients with Zollinger-Ellison syndrome were evaluated prospectively at the National Institutes of Health and 142 patients (66%) underwent standardized surgical exploration and resection. Eight patients (5.6%) (six men and two women; mean age, 41 years) had primary gastrinoma located in ectopic sites. Long-term follow-up was derived from a prospective database.

RESULTS

Ectopic gastrinoma tissue was identified and resected in the liver (three patients), common bile duct (one patient), jejunum (one patient), omentum (one patient), pylorus (one patient), and ovary (one patient). Seven patients (88%) were cured biochemically after resection and five patients (63%) have sustained cures, with a mean follow-up of 7.5 years (range, 0.4 to 11.7 years). One patient with a jejunal primary gastrinoma had a biochemical recurrence at 2 years, and another with a primary hepatic gastrinoma had a recurrence 6 years after resection. A patient with a pyloric primary gastrinoma was not cured.

CONCLUSIONS

Extraduodenal, extrapancreatic, and extranodal gastrinomas are encountered in 5.6% of patients who undergo exploration with curative intent. If no gastrinoma is found in the usual locations, other ectopic sites should be examined carefully. Resection of these primary ectopic tumors can lead to durable biochemical cures.

The biological relevance of gastric neuroendocrine tumors

Gastric neuroendocrine tumors were originally thought to have a low incidence (three percent). Since endoscopic diagnostic procedures have become clinical routine, they are now found more frequently (relative incidence up to 41 percent). In recent years, classifications have been developed that attempt to consider the biological relevance of these tumors. Four types of gastric neuroendocrine tumor may be distinguished: Type 1 gastric neuroendocrine tumor is most common. It is associated with chronic atrophic fundus gastritis, hypergastrinemia and often with pernicious anemia. Usually it is multicentric and smaller than one cm, does not produce any symptoms and has an excellent prognosis. Type 2 gastric neuroendocrine tumor is second in frequency. It has no association with other diseases, is solitary and has no predilection for a particular localization. It may be larger than 1 cm, produce a carcinoid syndrome or Zollinger-Ellison syndrome and have a metastasis rate of up to 30 percent. Type 3 gastric neuroendocrine tumor is rare and always associated with Zollinger-Ellison syndrome and multiple endocrine neoplasia type I. It occurs as multiple lesions in the gastric body fundus and has a lower metastatic rate than type 2 gastric neuroendocrine tumor. Type 4 gastric neuroendocrine tumor corresponds to a small-cell carcinoma.

Forty-year appraisal of gastrinoma. Back to the future

OBJECTIVE

The author analyzed potential survival determinants in gastrinoma to characterize a possible uniform staging system and to determine whether complete surgical resection improves expected survival.

SUMMARY AND BACKGROUND DATA

Gastrinoma is an indolent yet malignant neuroendocrine tumor. The associated gastric acid hypersecretion can be controlled medically. Staging of gastrinoma is inconsistent and the role of surgical resection controversial.

METHODS

Seventy-four patients with gastrinoma with a minimum 5-year follow-up were assessed. Cox's proportional hazards regression model was used to examine the association of risk factors with survival.

RESULTS

The following factors had no effect on survival: age at diagnosis, sex, presence of lymph node metastases, associated multiple endocrine neoplasia, and method of ulcer treatment. The three unique determinants of survival were primary tumor size (relative risk, 1.534; p = 0.0005), liver metastases (relative risk, 2.947; p = 0.0209), and complete surgical resection (relative risk, 0.163; p = 0.0076). On the basis of these risk factors, a uniform staging system is proposed and predictive survival curves developed.

CONCLUSIONS

The primary determinants of survival in gastrinoma are the size of the primary tumor and liver metastases. Complete surgical resection reduces mortality, regardless of other factors.

Use of selective arterial secretin injection test to guide surgery in patients with Zollinger-Ellison syndrome

It is often difficult to localize gastrinomas in patients with Zollinger-Ellison syndrome (ZES). We have developed a new useful method, the selective arterial secretin injection test (SASI test), for localizing gastrinomas in patients with ZES. The SASI test first determines the arteries feeding the gastrinomas and then locates the gastrinomas. In 12 patients with ZES, the SASI test clearly localized the gastrinomas, while results obtained with computed tomography or portal venous blood sampling had a positive predictability of less than 10%. Following localization with the SASI test, curative resection of gastrinomas was successfully performed on 7 patients who consented to the operation. Each of 3 patients had one duodenal submucosal microgastrinoma and one or more metastatic lymph node; the other 4 patients had 2 to 10 microgastrinomas or large gastrinomas in the duodenum or the pancreas. All 7 patients, who exhibited negative responses with a postoperative secretin test, have been completely cured from 3 months to 4 years postoperatively. The usefulness of the SASI test for preoperative evaluation is demonstrated by the fact that it gives a 100% positive predictability rate as well as a 100% negative predictability rate. Hence the SASI test precisely locates functioning gastrinomas.

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.

Biologic behavior of sporadic gastrinoma located to the right and left of the superior mesenteric artery

Among a series of 107 closely followed patients with gastrinoma, 60 patients with sporadic type tumors were identified and evaluated. There were 44 patients (73%) with tumors to the right of the superior mesenteric artery (SMA). Of these, 16 (36%) had extrapancreatic tumors, 28 (64%) had tumor within lymph nodes, and 9 (20%) had multiple tumors. In this group of patients, there were 19 (43%) cures, and only 9 (20%) patients had hepatic metastases. In contrast, in 16 patients (27%) with tumors to the left of the SMA, there were no extrapancreatic tumors, only 3 patients (19%) had tumor within lymph nodes, and 7 (44%) had multiple tumors. In this group, there was only one cure (6%), and nine (56%) patients had hepatic metastases. These findings suggest two distinct populations of sporadic gastrinoma, one to the right (gastrinoma triangle) and the other to the left (outside triangle) of the SMA, which appear to have different biologic behaviors. These differences may reflect divergent etiologies for these two groups of tumors.

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.

Clinicopathological characteristics of duodenal microgastrinomas

Duodenal gastrinomas do not seem to behave as malignantly as sporadic pancreatic gastrinomas. Statistical analysis of 49 patients with sporadic pancreatic gastrinoma and 21 patients with sporadic duodenal gastrinoma reported since 1980 in Japan revealed that the incidence of hepatic metastasis was 57% in patients with sporadic pancreatic gastrinoma and only 9% in patients with sporadic duodenal gastrinoma (p less than 0.01). These findings suggest that there is an essential biological differences between duodenal and pancreatic gastrinoma. Five patients with sporadic duodenal microgastrinoma (tumor diameter less than 5mm) in our hospital had no hepatic metastases; however, 4 patients had lymph node metastases. Immunohistochemical study of 5 sporadic duodenal microgastrinomas and 6 sporadic pancreatic gastrinomas revealed that the sporadic duodenal gastrinomas contained significantly fewer insulin-producing or glucagon-producing cells than sporadic pancreatic gastrinomas. The cellular composition of the metastatic lymph nodes from duodenal microgastrinomas was similar to that of the primary tumor. This difference in cellular composition between the duodenal microgastrinomas and the pancreatic gastrinomas suggests that the process of development and differentiation of gastrinoma cells is different.

Effects of curative gastrinoma resection on gastric secretory function and antisecretory drug requirement in the Zollinger-Ellison syndrome

The chronic hypergastrinemia in diseases such as the Zollinger-Ellison syndrome has trophic effects on the gastric mucosa, causing increased parietal cell mass reflected by increased maximal acid output (MAO) and basal acid output (BAO). The time course for the development of these gastric changes in humans is unknown, and controversy exists regarding whether reversal of the hypergastrinemia results in rapid normalization of gastric secretory function. To address these uncertainties, gastric secretory function was prospectively evaluated in 20 patients with the Zollinger-Ellison syndrome undergoing successful curative resection of gastrinoma. Each patient had gastric acid measurements, imaging studies, fasting serum gastrin and secretin provocative testing preoperatively, postoperatively at 3-6 months, and yearly thereafter. Preoperative mean BAO was 39 mEq/h, MAO 56 mEq/h, BAO-MAO ratio 0.73, and fasting gastrin output 1020 pg/mL. All patients were evaluated at 6 months, 17 at 1 year, 15 at 2 years, 13 at 3 years, and 9 at 4 years. By 3-6 months, MAO decreased by 50% in men (mean, 30 mEq/h) and by 35% in women (mean, 29 mEq/h) and then remained relatively unchanged for up to 4 years. Before surgery, 14 of 20 patients (70%) had an elevated MAO, whereas 4 years after resection, none of 9 patients had elevated levels. By 3-6 months, BAO decreased by 75% and remained unchanged for up to 4 years. At 3-6 months, 56% of patients were mild hypersecretors and 67% remained hypersecretors up to 4 years. Preoperatively, the BAO-MAO ratio was elevated in 16 of 20 patients (80%); postoperatively, only 5 of 18 patients (28%) at 3-6 months, 2 of 15 (13%) at 1 year, and 2 of 10 (20%) at 4 years continued to have elevated ratios. Preoperatively, the mean ranitidine dose was 1597 mg/day, whereas after surgery the mean dose was 535 mg/day at 3-6 months and approximately 300 mg/day at 1-4 years with 8 patients requiring no antisecretory drug. These results show that the trophic effects of chronic hypergastrinemia are, in general, rapidly reversible with a 50% decrease in MAO within 3-6 months of cure. Similarly, BAO decreased by 75% within 3-6 months. Despite these decreases, careful monitoring of acid secretion is required after reversal of the chronic hypergastrinemia in diseases such as the Zollinger-Ellison syndrome, because 55% of patients at 3-6 months and up to 67% at 4 years continue to remain mild hypersecretors and require low doses of antisecretory drugs.

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).

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.

Zollinger-Ellison syndrome

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

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.

Anatomic distribution of pancreatic endocrine tumors

Pancreatic endocrine tumors are grouped together by their common histologic, cytochemical, and ultrastructural features. Although useful conceptually, this paradigm has been unable to predict the anatomic location of different tumor types. Successful surgical excision of these tumors would be facilitated by an improved understanding of their anatomic distribution. Based on the available data, a bimodal distribution of pancreatic endocrine tumors was identified. Cluster 1 (gastrinomas, pancreatic polypeptide (PP)-secreting tumors, somatostatinomas) had 75% of tumors to the right of the superior mesenteric artery, whereas cluster 2 (insulinoma, glucagonoma) had 75% of tumors to the left of the superior mesenteric artery (p less than 0.05). This distribution is similar to that distribution predicted based on the volume density of the corresponding islet cells for insulinoma, glucagonoma, and PP-secreting tumors, but not for somatostatinoma. These findings suggest that pancreatic endocrine tumors are derived from similar cytologic precursors as pancreatic islet cells, and their distribution may be a consequence of embryologic development from either the ventral (cluster 1) or dorsal (cluster 2) pancreatic buds.

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.

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.

Gastrin-producing ovarian cystadenocarcinoma: sensitivity to secretin and SMS 201-995

We report a patient with severe peptic ulcer disease and a right ovarian mass that was found to be a gastrin-producing cystadenocarcinoma. Gastrin production by the tumor was stimulated by secretin and inhibited by the long-acting somatostatin analogue SMS 201-995. Following resection of the tumor, serum gastrin levels and the gastrin response to secretin returned to normal. Histologic examination, including Alcian blue staining for mucin and immunoperoxidase staining for gastrin, revealed gastrin at the base and mucin at the apex of the tumor cells. This report demonstrates secretin stimulation and somatostatin inhibition of gastrin secretion from a cell that is apparently not of endocrine origin.

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.

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.