Surgery to cure the Zollinger-Ellison syndrome

BACKGROUND AND METHODS

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

RESULTS

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

CONCLUSIONS

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

The gastrinoma triangle: operative implications

Operative experience with 45 gastrinoma patients has led to the identification of an anatomic area where occult tumors can be discovered and where excision of these tumors had led to apparent cure. Of 36 patients with histologically confirmed gastrinomas, 27 patients (75 percent) had obvious and 9 patients (25 percent) had occult tumors. All nine occult lesions were found within an anatomic triangle defined by the junction of the cystic and common bile ducts superiorly, the junction of the second and third portions of the duodenum inferiorly, and the junction of the neck and body of the pancreas medially. Although occult tumors from three patients (in the lymph nodes in two patients and in the duodenum in one patient) were removed primarily for histologic diagnosis, postoperative serum gastrin levels have remained within the normal range (follow-up of 86 to 99 months). Two patients had excision of the tumor with intent to cure. One patient with a solitary duodenal tumor was apparently cured but committed suicide 3 months postoperatively. The other patient had both obvious primary and occult metastatic tumors within the triangle and was eugastrinemic 9 months after excision. In all patients in whom tumor was found, it was locally excised, and no patient was subjected to radical pancreatic resection. There were no postoperative complications related to tumor removal. An aggressive approach towards curative tumor excision is now advocated for all gastrinoma patients who are suitable operative risks and have no evidence preoperatively of liver metastases or the multiple endocrine neoplasm-type I syndrome.

Intraoperative ultrasonographic localization of islet cell tumors. A prospective comparison to palpation

The purpose of the present study was to evaluate prospectively the value of intraoperative ultrasound scanning (IOUS) in localizing islet cell tumors by comparing results of IOUS to those of palpation during 44 consecutive laparotomies for gastrinoma (36) or insulinoma (8). All patients had preoperative radiographic imaging studies and selective venous sampling for hormones, which guided the subsequent laparotomy. Any suspicious finding by palpation and/or IOUS was resected. Pathologic evidence of islet cell neoplasm served as the reference standard. Five patients were excluded from analysis because neither palpation nor IOUS had suspicious findings and no islet cell tumor was found. Seven pancreatic insulinomas were found in seven patients. IOUS was as sensitive as palpation at localizing insulinomas. Twenty-three pancreatic gastrinomas were found in 19 patients. IOUS was equal to palpation in the ability to localize gastrinomas. Gastrinomas that were successfully imaged by IOUS were significantly larger than gastrinomas that were not imaged. Twelve extrapancreatic gastrinomas were found in nine patients, and palpation was more sensitive than IOUS at localizing these small duodenal wall tumors. Five patients (11%) had their surgical management changed by IOUS. Two patients had pancreatic tumors (one gastrinoma and insulinoma) enucleated that would not have been found without IOUS, and three patients had resections of pathologically proven malignant islet cell tumors based on sonographic findings. All five patients were cured with short follow-up. The present results demonstrate that palpation and IOUS are complementary because IOUS can image tumors that are not palpable and IOUS can provide additional information concerning malignant potential not detected by palpation.

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.

Morbidity and mortality of aggressive resection in patients with advanced neuroendocrine tumors

BACKGROUND

There is considerable controversy about the treatment of patients with malignant advanced neuroendocrine tumors of the pancreas and duodenum. Aggressive surgery remains a potentially efficacious antitumor therapy but is rarely performed because of its possible morbidity and mortality.

HYPOTHESIS

Aggressive resection of advanced neuroendocrine tumors can be performed with acceptable morbidity and mortality rates and may lead to extended survival.

DESIGN

The medical records of patients with advanced neuroendocrine tumors who underwent surgery between 1997 and 2002 by a single surgeon at the University of California, San Francisco, were reviewed in an institutional review board-approved protocol.

MAIN OUTCOME MEASURES

Surgical procedure, pathologic characteristics, complications, mortality rates, and disease-free and overall survival rates were recorded. Disease-free survival was defined as no tumor identified on radiological imaging studies and no detectable abnormal hormone levels. Proportions were compared statistically using the Fisher exact test. Kaplan-Meier curves were used to estimate survival rates.

RESULTS

Twenty patients were identified (11 men and 9 women). Of these, 10 (50%) had gastrinoma, 1 had insulinoma, and the remainder had nonfunctional tumors; 2 had multiple endocrine neoplasia type 1, and 1 had von Hippel-Lindau disease. The mean age was 55 years (range, 34-72 years). In 10 patients (50%), tumors were thought to be unresectable according to radiological imaging studies because of multiple bilobar liver metastases (n = 6), superior mesenteric vein invasion (n = 3), and extensive nodal metastases (n = 1). Tumors were completely removed in 15 patients (75%). Surgical procedures included 8 proximal pancreatectomies (pancreatoduodenectomy or whipple procedure), 3 total pancreatectomies, 9 distal pancreatectomies, and 3 tumor enucleations from the pancreatic head. Superior mesenteric vein reconstruction was done in 3 patients. Liver resections were done in 6 patients, and an extended periaortic node dissection was performed in 1. The spleen was removed in 11 patients, and the left kidney was removed as a result of tumor metastases in 2. Eighteen patients had primary pancreatic tumors, and 2 had duodenal tumors; 2 patients with multiple endocrine neoplasia type 1 had both pancreatic and duodenal tumors. The mean tumor size was 8 cm (range, 0.5-23 cm). Of the patients, 14 (70%) had lymph node metastases and 8 (40%) had liver metastases. The mean postoperative hospital stay was 11.5 days (range, 6-26 days). Six patients (30%) had postoperative complications. There was a significantly greater incidence of pancreatic fistulas with enucleations compared with resections (P =.04). There were no operative deaths. The mean follow-up period was 19 months (range, 1-96 months); 18 patients (90%) are alive, 2 died of progressive tumor, and 12 (60%) are disease-free. The actuarial overall survival rate is 80% at 5 years, and disease-free survival rates indicate that all tumors will recur by the 7-year follow-up visit.

CONCLUSIONS

Aggressive surgery including pancreatectomy, splenectomy, superior mesenteric vein reconstruction, and liver resection can be done with acceptable morbidity and low mortality rates for patients with advanced neuroendocrine tumors. Although survival rates following surgery are excellent, most patients will develop a recurrent tumor. These findings suggest that conventional contraindications to surgical resection, such as superior mesenteric vein invasion and nodal or distant metastases, should be reconsidered in patients with advanced neuroendocrine tumors.

Zollinger-Ellison syndrome: current concepts and management

Over the last few years the approach to managing patients with the Zollinger-Ellison syndrome has changed dramatically. The establishment of gastrin hypersecretion by a non-beta islet cell tumor as responsible for the gastric acid hypersecretion, and the subsequent development and widespread availability of gastrin radioimmunoassays have changed the criteria generally used for diagnosis and have led to an increased understanding of syndromes that can mimic Zollinger-Ellison syndrome. With the availability of histamine H2-receptor antagonists, gastric acid hypersecretion can be controlled medically in almost all patients with Zollinger-Ellison syndrome, obviating routine total gastrectomy. With the reduced mortality from gastric acid hypersecretion, increased attention is being focused on the natural history of the gastrinoma. Newer methods of localizing tumors are being investigated with a view to surgical removal of the gastrinoma, and the importance of developing an affective chemotherapeutic regimen is becoming increasingly apparent.

Comparison of surgical results in patients with advanced and limited disease with multiple endocrine neoplasia type 1 and Zollinger-Ellison syndrome

OBJECTIVE

To determine the role of surgery in patients with Zollinger-Ellison syndrome (ZES) and multiple endocrine neoplasia type 1 (MEN1) with either limited or advanced pancreatic endocrine tumors (PETs).

SUMMARY BACKGROUND DATA

The role of surgery in patients with MEN1 and ZES is controversial. There have been numerous previous studies of surgery in patients with PETs; however, there are no prospective studies on the results of surgery in patients with advanced disease.

METHODS

Eighty-one consecutive patients with MEN1 and ZES were assigned to one of four groups depending on the results of imaging studies. Group 1 (n = 17) (all PETs smaller than 2.5 cm) and group 3 (n = 8) (diffuse liver metastases) did not undergo surgery. All patients in group 2A (n = 17; single PET 2.5-6 cm [limited disease]) and group 2B (n = 31; two or more lesions, 2.5 cm in diameter or larger, or one lesion larger than 6 cm) underwent laparotomy. Tumors were preferably removed by simple enucleation, or if not feasible resection. Patients were reevaluated yearly.

RESULTS

Pancreatic endocrine tumors were found in all patients at surgery, with groups 2A and 2B having 1.7 +/- 0.4 and 4.8 +/- 1 PETs, respectively. Further, 35% of the patients in group 2A and 88% of the patients in group 2B had multiple PETs, 53% and 84% had a pancreatic PET, 53% and 68% had a duodenal gastrinoma, 65% and 71% had lymph node metastases, and 0% and 12% had liver metastases. Of the patients in groups 2A and 2B, 24% and 58% had a distal pancreatectomy, 0% and 13% had a hepatic resection, 0% and 6% had a Whipple operation, and 53% and 68% had a duodenal resection. No patient was cured at 5 years. There were no deaths. The early complication rate, 29%, was similar for groups 2A and 2B. Mean follow-up from surgery was 6.9 +/- 0.8 years, and during follow-up liver metastases developed in 6% of the patients in groups 2A and 2B. Groups 1, 2A, and 2B had similar 15-year survival rates (89-100%); they were significantly better than the survival rate for group 3 (52%).

CONCLUSIONS

Almost 40% of patients with MEN1 and ZES have advanced disease without diffuse distant metastases. Despite multiple primaries and a 70% incidence of lymph node metastases, tumor can be removed with no deaths and complication rates similar to those in patients with limited disease. Further, despite previous studies showing that patients with advanced disease have decreased survival rates, in this study the patients with advanced tumor who underwent surgical resection had the same survival as patients with limited disease and patients without identifiable tumor. This suggests that surgical resection should be performed in patients with MEN1 who have ZES and advanced localized PET.

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).

Surgery in Zollinger-Ellison syndrome alters the natural history of gastrinoma

OBJECTIVE

The authors assessed the impact of gastrinoma resection on the subsequent development of hepatic metastases in Zollinger-Ellison syndrome.

SUMMARY BACKGROUND DATA

The symptoms of acid hypersecretion can be controlled medically in Zollinger-Ellison syndrome with high-dose pharmacologic therapy. The current role of surgery is curative excision of the gastrinoma. Because biochemical cure is obtained only in a portion of the patients and the neoplastic disease may be indolent in this syndrome, the ability of surgical resection of gastrinoma to alter or improve the subsequent development of hepatic metastases and mortality has not been defined.

METHODS

One hundred twenty-four patients with the biochemical diagnosis of Zollinger-Ellison syndrome and no hepatic metastases on initial imaging studies were evaluated. Ninety-eight patients underwent surgical exploration for curative gastrinoma resections while 26 patients were managed medically. Long-term follow-up regarding development of hepatic metastases and survival were evaluated.

RESULTS

Surgical exploration with gastrinoma excision resulted in a significantly decreased incidence of hepatic metastases 3% (3/98) compared with patients managed medically 23% (6/26) with comparable follow-up (p < 0.003). Two deaths due to metastatic gastrinoma occurred in the nonoperative group compared with no disease-specific deaths in the surgical group (p = 0.085).

CONCLUSIONS

For the patient with Zollinger-Ellison syndrome without metastatic disease, surgical exploration with attempted curative gastrinoma resection is recommended because it may alter the natural history of this syndrome.

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.

Nutritional consequences of total gastrectomy

Nutritional status was investigated in 10 patients who had previously undergone total gastrectomy without evidence of malignancy. The ability of these patients to ingest and absorb adequate amounts of nutrients was examined. Metabolic balance studies were also performed to discover how effectively these patients could accumulate and use the absorbed nutrients. In the controlled hospital situation, the amount of food ingested was greater than the amount required for maintenance of Ideal Body Weight. Although mild malabsorption of fat and nitrogen was documented, weight gain and positive nitrogen balance occurred. In direct contrast, food intake significantly decreased when the patients returned to their home environment. While severe malabsorption may contribute to malnutrition in the individual patient, the most common mechanism responsible for postoperative malnutrition was inadequate intake. In the occasional patient with severe malabsorption, the universal demonstration of jejunal anaerobic bacterial overgrowth offers important therapeutic implications. The relative importance of pancreatico-biliary insufficiency in promoting malabsorption remains to be determined. Construction of a Hunt-Lawrence jejunal pouch was not found to favorably affect caloric intake, weight gain, degree of malabsorption, or dumping symptoms. Although some degree of malnutrition does result from total gastric resection, in most cases it is mild and potentially correctable. Avoidance of indicated total gastrectomy due to fears of progressive postoperative malnutrition is unwarranted.

The role of surgery in the Zollinger-Ellison syndrome

When the Zollinger-Ellison syndrome was first identified, total gastrectomy was proposed as the most effective treatment for the secretory manifestations of the syndrome. Recently, however, great enthusiasm has developed for medical treatment by means of H2-receptor antagonists. The authors have cared for 27 patients with the Zollinger-Ellison syndrome at The University of Texas Medical Branch in the past 12 years and have been pleased with the results of total gastrectomy, which was performed in 23 of the 27 patients (one patient refused operation and three patients had lesser gastric operations). Twenty-three patients underwent total gastrectomy with Roux-en-Y esophagojejunostomy. There were no operative deaths. Primary tumors were found in 17 patients, seven of whom also had metastatic tumors. No tumors were found in nine patients. Nine patients are dead; the actuarial survival rate for all patients was 75% at 5 years and 52% at 10 years. Eleven of the 27 patients had the multiple endocrine neoplasia I syndrome. Of the 18 survivors, only three have normal serum gastrin levels, and all three had extrapancreatic gastrinomas, one in peripancreatic lymph nodes, one in the liver, and one in a cystic tumor attached to the stomach. Nutritional results were good to excellent, with a mean postoperative weight loss of 14.7% (mean follow-up period was 45 months). The authors conclude that treatment of the hypersecretory problems of the Zollinger-Ellison syndrome by total gastrectomy is safe and dependable. Results compare well with those of long-term medical management, whose success is dependent upon serial favorable responses to a lifetime of repeated challenges.

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.

Does the use of routine duodenotomy (DUODX) affect rate of cure, development of liver metastases, or survival in patients with Zollinger-Ellison syndrome?

OBJECTIVE

To determine whether routine use of duodenotomy (DUODX) alters cure rate, survival, or development of liver metastases in 143 patients (162 operations) with Zollinger-Ellison syndrome (ZES) without MEN1.

SUMMARY BACKGROUND DATA

DUODX has been shown to increase the detection of duodenal gastrinomas, but it is unknown if it alters rate of cure, liver metastases, or survival. Data from our prospective studies of surgery in ZES allow us to address this issue because DUODX was not performed before 1987, whereas it was routinely done after 1987.

METHODS

All patients with sporadic ZES (non-MEN1) undergoing surgery for possible cure without a prior DUODX from November 1980 to June 2003 were included. Patients had preoperative computed tomography (CT), magnetic resonance imaging (MRI), or ultrasound; if unclear, angiography and somatostatin receptor scintigraphy since 1994. At surgery, all had the same standard ZES operation and were assessed immediately postoperatively, at 3 to 6 months, and yearly for cure (fasting gastrin, secretin test. and imaging studies).

RESULTS

A DUODX was performed in 79 patients (94 operations), and no DUODX was performed in 64 patients (68 operations), with 10 patients having both (no DUODX, then a DUODX later). Gastrinoma was found in 98% with DUODX compared with 76% with no DUODX (P < 0.00001). Duodenal gastrinomas were found more frequently with DUODX (62% vs. 18%; P < 0.00001), whereas pancreatic, lymph node, and other primary gastrinomas occurred similarly. Six of the 10 patients with 2 operations had a duodenal tumor found with DUODX during a second operation that was missed in the first operation without DUODX. Both the immediate postoperative cure rate (65% vs. 44%; P = 0.010) and long-term cure rate at last follow-up (8.8 +/- 0.4 years; range, 0.1 to 21.5) (52% vs. 26%; P = 0.0012) were significantly greater with a DUODX than without. In patients without pancreatic tumors or liver metastases at surgery, both the rate of developing liver metastases (6% vs. 9.5%) and the disease-related death rate (0% vs. 2%) were low and not significantly different in patients with or without a DUODX.

CONCLUSIONS

These results demonstrate that routine use of DUODX increases the short-term and long-term cure rate due to the detection of more duodenal gastrinomas. The rate of development of hepatic metastases and/or disease-related mortality in patients without pancreatic tumors is low, and no effect of DUODX on these parameters was seen. Duodenotomy (DUODX) should be routinely performed during all operations for cure of sporadic ZES.

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

OBJECTIVE

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

SUMMARY BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

A prospective study of intraoperative methods to diagnose and resect duodenal gastrinomas

OBJECTIVE

This study determined, prospectively, whether duodenotomy (DX) should be routinely performed in explorations for patients with Zollinger-Ellison syndrome (ZES).

SUMMARY BACKGROUND DATA

Duodenal gastrinomas are now being found with increasing frequency in patients with Zollinger-Ellison syndrome. The surgical approach used to detect these tumors is controversial. Some recommend intraoperative endoscopy with transillumination (IOE) at surgery, while others recommend routine DX.

METHODS

Beginning in 1989, the authors prospectively compared the ability of palpation, intraoperative ultrasound (IOUS), IOE, and DX (in that sequence) to detect gastrinomas in 35 consecutive patients with ZES. Each patient also underwent preoperative localization studies.

RESULTS

Thirty-three of 35 patients (94%) had tumor detected and excised; duodenal gastrinomas were excised in 27 patients (77%). The average size of the duodenal tumors was 0.8 cm, significantly smaller (p < 0.005) than the pancreatic and lymph node tumors in this series. Standard palpation after a Kocher maneuver identified 19 of the 31 duodenal tumors (61%) in the 27 patients. IOUS revealed only eight duodenal tumors (26%) and no new lesions. IOE identified 20 duodenal gastrinomas (64%) and 6 new lesions. DX identified 31 duodenal tumors (100%) and 5 additional tumors. The morbidity rate was 17%. One patient had a duodenal fistula after operation (2.8%) and subsequently recovered. No patient died.

CONCLUSIONS

These results demonstrate that the duodenum is the most common location for gastrinoma in patients with ZES (77%) and that DX to detect and remove duodenal gastrinomas should be routinely performed in all explorations for patients with ZES.

Assessment and prediction of long-term cure in patients with the Zollinger-Ellison syndrome: the best approach

OBJECTIVE

To identify the best method for determining freedom from disease after gastrinoma resection and for predicting long-term disease-free status in patients with the Zollinger-Ellison syndrome.

DESIGN

Prospective study in consecutive patients.

SETTING

Referral-based clinical research center.

PATIENTS

Eighty-one consecutive patients with the Zollinger-Ellison syndrome who underwent surgical exploration for gastrinoma resection.

INTERVENTION

Patients were evaluated after gastrinoma resection, before discharge, 3 to 6 months after surgery, and yearly thereafter. Evaluation included secretin provocative testing and fasting serum gastrin determinations. Follow-up examinations after the initial postoperative evaluations included a clinical assessment, acid secretion studies, a calcium provocative test, and various imaging studies.

MEASUREMENTS AND MAIN RESULTS

Most patients (96%) had gastrinomas. Freedom from disease was defined by improved symptoms, reduced acid output and antisecretory drug requirements, and a normal gastrin level, normal imaging studies, and negative gastrin provocative studies. Fifty-two percent of patients (n = 42) were disease-free immediately after surgery, 44% at 3 to 6 months, 42% at 1 year, and 35% by 5 years (mean follow-up, 39 months). The secretin provocative test was the first test to become positive in 45% of patients with a recurrence, the serum gastrin determination was the first test to become positive in 36%, and both tests became positive at the same time in 18%. No recurrence was first detected by imaging studies or by calcium provocative testing. Fasting serum gastrin levels and secretin provocative test results at different postoperative times can be used to predict the probability of a patient remaining disease free at 3 years. Patients with a normal gastrin level and a normal secretin provocative test immediately after surgery had a 3-year disease-free probability of 75%, and normal results on both tests at 6 months, 1 year, and 2 years yielded respective probabilities of 88%, 95%, and 100%.

CONCLUSIONS

Both the secretin provocative test and fasting serum gastrin determination are necessary for the early diagnosis of cases of recurrent disease after gastrinoma resection. The calcium provocative test and imaging studies do not detect any recurrences first. Fasting serum gastrin determinations and secretin provocative testing at different postoperative times can be used to predict the probability of a patient remaining disease free at 3 years.

Prospective study of surgical resection of duodenal and pancreatic gastrinomas in multiple endocrine neoplasia type 1

BACKGROUND

The role of surgical resection of gastrinoma in multiple endocrine neoplasia type 1 (MEN 1) is controversial because of low biochemical cure rates, but with adequate duodenal exploration higher cure rates may be possible.

METHODS

We have prospectively evaluated this proposal in ten consecutive patients with MEN 1 and Zollinger-Ellison syndrome who underwent surgical exploration for gastrinoma resection including a detailed evaluation of the duodenum by palpation, intraoperative endoscopy with transillumination, and duodenotomy.

RESULTS

Duodenal tumors were present in seven patients. Six of seven patients had metastatic deposits in lymph nodes, and two of seven had synchronous pancreatic tumors. Three patients had a single duodenal tumor, one patient had two tumors, and three patients had more than 20 duodenal tumors. Positive gastrin staining by use of immunohistochemistry was seen in all duodenal tumors. None of these seven patients were biochemically cured. Of three patients with negative duodenal explorations, two had single pancreatic tumors removed and one had only lymph node gastrinoma. No patients were biochemically cured.

CONCLUSIONS

Not all patients with MEN 1 and Zollinger-Ellison syndrome have duodenal gastrinomas. In the 70% of patients with duodenal tumors, even extensive duodenal exploration with removal of positive lymph nodes does not result in cures because 86% of tumors had metastasized to lymph nodes and 43% of patients had large numbers of tumors.

Current concepts in the surgical management of multiple endocrine neoplasia type 1 pancreatic-duodenal disease. Results in the treatment of 40 patients with Zollinger-Ellison syndrome, hypoglycaemia or both

The management of multiple endocrine neoplasia type 1 (MEN-1) pancreatic-duodenal disease, particularly when the Zollinger-Ellison syndrome (ZES) is the presenting manifestation, has remained controversial. The management of hypoglycaemia and other syndromes as well as large tumours detected by imaging is less controversial, although standardized surgical techniques have not been generally adapted. The rationale for an aggressive operative management plan for ZES and other syndromes is based on the facts that neuroendocrine tumours of both the pancreas and the duodenum have malignant potential and that the functional manifestations can be controlled with appropriate surgical procedures based on current concepts of the MEN-1 disease. Of the ten concepts presented, the one critical to the surgical treatment of ZES is that a duodenotomy is essential in detecting the source of hypergastrinaemia in most MEN-1 patients. The complete operation is multifaceted and includes peripancreatic lymph node dissection (ZES), enucleation of any head or uncinate tumours and a distal pancreatectomy. Our results in 40 MEN-1 patients with functional syndromes treated with these procedures are encouraging. Ten patients with hypoglycaemia (four with concomitant ZES) have been 'cured' with follow-up as long as 18 years. Sixty-eight per cent of 34 patients with ZES have remained eugastrinaemic during follow-up as long as 19 years. One patient developed a solitary liver metastasis that was excised a year ago without other evidence of recurrence. There has been no operative mortality and three subsequent deaths were due to unrelated disease.

Aggressive resection of metastatic disease in selected patients with malignant gastrinoma

Fifteen patients with Zollinger-Ellison syndrome followed at the National Institutes of Health with extensive metastatic disease had an actuarial 5-year survival of 20%. Therefore, in 1982 a prospective study to examine the effect and feasibility of removing all gross tumor in selected patients with extensive metastatic disease was instituted. Five patients with extensive metastatic gastrinoma confined to the abdomen in whom imaging studies suggested the possibility of complete surgical resection were entered into this study and underwent attempted complete surgical resection and chemotherapy with streptozotocin, doxorubicin, and 5-fluorouracil. Median follow-up was 24 months. Surgical resection of all gastrinoma was possible in 4/5 patients attempted. In one patient in whom all gross disease could not be resected, the residual tumor progressed and the patient died 19 months after operation. All four patients with all disease resected appeared to benefit since all of them had a significant reduction in antisecretory medications and are enjoying normal activity and work. Three patients have had no detectable tumor on follow-up, and two of these patients are clinically and biochemically "cured" with normal fasting gastrin levels and negative provocative gastrin tests at 14 and 32 months. Therefore, aggressive resection of metastatic disease in selected patients with malignant gastrinoma is recommended.

Results of surgical management in 92 consecutive patients with Zollinger-Ellison syndrome

Hospital records and follow-up information on 92 patients with surgically proven Zollinger-Ellison syndrome have been reviewed, and data relating to symptomatology, age and sex incidence, pathologic findings, and early and late results of surgical procedures have been summarized. The postoperative mortality rate was 15%, and was adversely affected by previous peptic ulcer surgery, by the necessity of urgent operation for complications of peptic ulcer, and by employment of a procedure that failed to control acid secretion. Thirteen patients were found to have primary gastrinomas of the duodenum and an additional 13 patients had islet cell hyperplasia without evidence of frank neoplasm; prognosis in these two groups appears to be particularly favorable. Despite the current availability of effective nonoperative measures for control of gastric hypersecretion, surgical exploration is warranted in all patients to determine location and extent of tumor and to attempt to control the ulcer diathesis by resection of tumor. Long-term therapy with H2 receptor antagonists is advised for patients whose hypersecretory state has not been alleviated by tumor resection or whose gastrinoma cannot be removed. Total gastrectomy is still indicated in patients whose tumors are not amenable to resection and who are resistant to, or cannot follow, a rigid medical regimen.

Surgery on neuroendocrine tumours

Neuroendocrine tumours of the gastrointestinal tract and pancreas present a major challenge to physicians in their recognition and treatment requirements, and surgical treatment of these tumours has become increasingly important for symptom palliation and survival. For some carcinoid tumours the extent of surgery may depend on tumour size. Midgut carcinoid is the most common cause of the carcinoid syndrome, requiring surgery for primary and mesenteric tumours to minimize the risk for abdominal complications but also for removal of liver metastases to palliate hormonal symptoms. Among endocrine pancreatic tumours, insulinoma and gastrinoma often cause severe symptoms of hormone excess despite their inconspicuous size, but they can be successfully removed with improved pre- and intraoperative localization. Other tumours--glucagonoma, VIPoma, and non-functioning endocrine pancreatic tumours--are often large or metastasizing, but generally require surgical debulking to alleviate hormonal symptoms and have favourable survival.