Localization, malignant potential, and surgical management of gastrinomas

Zollinger-Ellison Syndrome Associated with von Recklinghausen Disease: Case Report and Literature Review

BACKGROUND

Pancreatic endocrine tumors (PETs) are rare and can occur as part of neurofibromatosis type 1 (NF1). Gastrinomas are functional PETs that are rarely associated with NF1. Only two cases of their occurrence have been reported in the literature.

CASE REPORT

A 28-year-old woman was admitted for further evaluation of epigastric soreness, heartburn, nausea, vomiting, diarrhea, and a significant weight loss. Physical examination was remarkable for cutaneous findings (axillary freckling and multiple café-au-lait spots) as well as neurofibromas (dermal, plexiform). A diagnosis of NF1 was confirmed. Esophagogastroduodenoscopy (EGD) revealed multiple ulcers in the duodenum and the upper jejunum. A fasting gastrin level exceeded ten times the normal limit. An abdominal multi-slice 128 computed tomography (CT) scan revealed an oval mass of 26 mm in diameter adjacent to the second section of the duodenum. The patient was examined carefully to rule out multiple endocrine neoplasia type 1 (MEN1). Surgical resection was performed and a gastrinoma, causing Zollinger-Ellison syndrome (ZES), was diagnosed by histological examinations of the extirpated mass. The serum gastrin level decreased to normal limits shortly after surgery. Continuous follow-up revealed that the symptoms and the EGD findings completely resolved without recurrences.

CONCLUSIONS

Although NF1 has common skeletal, visual, neurological, and cardiovascular complications, it also has a rare association with duodenal or pancreatic gastrinomas. Vigilance for this possible association is important to promote timely and careful management to help eliminate serious and potentially life-threatening complications.

[Surgery for gastrinoma: Short and long-term results]

INTRODUCTION

Zollinger-Ellison syndrome (Z-E) is characterized by gastrin-secreting tumors, responsible for causing refractory and recurrent peptic ulcers in the gastrointestinal tract. The optimal approach and the extension of tumor resection remains the subject of debate.

METHODS

During the period February 2005 and February 2014, 6 patients with Z-E underwent surgery, 4 men and 2 women with a median age 46.8 years (22-61). Two patients were affected with multiple endocrine neoplasia type-1 (MEN-1). Fasting gastrin levels greater than 200pg/ml (NV: <100) was diagnostic. Radiologic imaging to localize the lesion included octreoscan 6/6, computer tomography (CT) 6/6, and endoscopic ultrasonography (EUS) 1/6.

RESULTS

The octreoscan was positive in 5 patients. The CT localized the tumor in the pancreas in 2 patients, in the duodenum in 3 patients (1 confirmed by EUS) and between the common bile duct and vena cava in one patient. The laparoscopic approach was used in 4 patients, 2 patients converted to open surgery. The following surgical techniques were performed: 2 pylorus-preserving pancreatico-duodenectomy (PPPD), one spleen-preserving distal pancreatectomy, one duodenal nodular resection, 1 segmental duodenectomy and one extrapancreatic nodular resection. Pathological studies showed lymph nodes metástasis in 2 patients with pancreatic gastrinomas, and in one patient with duodenal gastrinoma. The median follow-up was 76,83 months (5-108) and all patients presented normal fasting gastrin levels.

CONCLUSIONS

Surgery may offer a cure in patients with Z-E. The laparoscopic approach remains limited to selected cases.

Impact of lymphadenectomy on survival after surgery for sporadic gastrinoma

BACKGROUND

The study was undertaken to determine prognostic factors and the value of systematic lymphadenectomy on survival in sporadic gastrinoma.

METHODS

Patients with sporadic gastrinoma who underwent initial surgery during a 21-year period in two tertiary referral centres were analysed retrospectively with respect to clinical characteristics, operative procedures and outcome.

RESULTS

Forty-eight patients with a median age of 52 (range 22-73) years were analysed. Some 18 patients had pancreatic and 26 had duodenal gastrinomas, whereas the primary tumour remained unidentified in four patients. After a median postoperative follow-up of 83 (range 3-296) months, 20 patients had no evidence of disease, 13 patients were alive with disease, 11 patients had died from the disease and four had died from unrelated causes. In 41 patients who underwent potentially curative surgery, systematic lymphadenectomy with excision of more than ten lymph nodes resulted in a higher rate of biochemical cure after surgery than no or selective lymphadenectomy (13 of 13 versus 18 of 28 patients; P = 0·017), with a trend towards prolonged disease specific survival (P = 0·062) and disease-free survival (P = 0·120), and a reduced risk of death (0 of 13 versus 7 of 24 patients; P = 0·037). Negative prognostic factors for disease specific survival were pancreatic location (P = 0·029), tumour size equal to or larger than 25 mm (P = 0·003), Ki-67 index more than 5 per cent (P < 0·001), preoperative gastrin level 3000 pg/ml or more (P = 0·003) and liver metastases (P < 0·001). Sex, age, type of surgery and presence of lymph node metastases had no influence on disease free or disease specific survival.

CONCLUSION

In sporadic gastrinoma, systematic lymphadenectomy during initial surgery may reduce the risk of persistent disease and improve survival.

Multiple giant duodenal ulcers associated with duodenal gastrinoma

A 59-year-old Japanese man with a history of chronic hepatitis C and cirrhosis was admitted to hospital because of severe abdominal pain and diarrhea. His discomfort had begun 2 months earlier and was localized to the upper abdomen. Upper gastrointestinal endoscopy showed multiple ulcerative lesions from the duodenal bulb to the descending part of the duodenum, one of which was a giant ulcer that filled half of the intestinal lumen. Despite continuous intravenous lansoprazole therapy, his abdominal symptoms did not improve. Upper gastrointestinal endoscopy was again performed to detect the tumor, but it was difficult to observe the tumor with a conventional endoscope. We then inverted a transnasal endoscope into the duodenum, and this enabled us to detect a 15-mm submucosal tumor in the upper wall of the duodenal bulb. Examination of specimens from endoscopic ultrasonography fine-needle aspiration biopsy of the tumor revealed gastrinoma in the duodenal bulb. We decided to perform an operative resection. The patient's symptoms resolved after surgery, and he remained asymptomatic at follow-up 18 months later. Therefore, when it is difficult to detect the tumor directly by conventional endoscopy, we recommend that attempts be made to detect the tumor by inverting a transnasal endoscope into the duodenal bulb.

Tailored imaging of islet cell tumors of the pancreas amidst increasing options

Pancreatic islet cell tumors are neuroendocrine tumors, which can produce hormones and can arise as part of multiple endocrine neoplasia type 1 or von-Hippel-Lindau-disease, two genetically well-defined hereditary cancer syndromes. Currently, technical innovation improves conventional and specific molecular imaging techniques. To organize the heterogeneous results described for the imaging of these tumors, we distinguished three indications (1) imaging of a patient with hormone hypersecretion, (2) search for a pancreatic primary in case of proven neuroendocrine cancer of unknown primary, and (3) screening of asymptomatic mutation carriers. We searched for publications on imaging of islet cell tumors between 1995 and January 2010 and defined a Level of Evidence (LOE) for the applicability of each technique. For each technique, data were analyzed in a Forest plot and arranged per imaging indication and tumor subtype. LOEs are weak for all imaging techniques. Analyses indicate a prominent role for endoscopic ultrasound for all three indications.

Five-Year Long-Term Followup of a Primary Lymph node Gastrinoma: Is a Pancreaticoduodenectomy Justified?

Background. Gastrinoma-positive lymph nodes and failed localization of the primary tumor during surgical exploration are described. Specialists suppose that these lymph nodes are metastases rather than a primary gastrinoma. Methods. Case report with a five-year long-term followup. A 60-year-old patient with an confirmed gastrinoma was treated in our department. All preoperative evaluations including somatostatin-receptor-scintigraphy and F-Dopa PET failed to localize the gastrinoma. Explorative laparotomy revealed a gastrinoma in two peripancreatic lymph nodes. Despite extensive intraoperative exploration, no primary gastrinoma could be detected in typical localization. Results. Over a period of 5 years, the patient's gastrin level stayed in the normal range and the patient seems to be completely cured. Conclusion. A prophylactic partial pancreatoduodenectomy is not indicated to avoid recurrence, since complete biochemical cure by local resection of the lymph node gastrinoma is possible.

Inherited pancreatic endocrine tumor syndromes: advances in molecular pathogenesis, diagnosis, management, and controversies

Pancreatic endocrine tumors (PETs) can occur as part of 4 inherited disorders, including Multiple Endocrine Neoplasia type 1 (MEN1), von Hippel-Lindau disease (VHL), neurofibromatosis 1 (NF-1) (von Recklinghausen disease), and the tuberous sclerosis complex (TSC). The relative frequency with which patients who have these disorders develop PETs is MEN1>VHL>NF-1>TSC. Over the last few years, there have been major advances in the understanding of the genetics and molecular pathogenesis of these disorders as well in the localization and the medical and surgical treatment of PETs in such patients. The study of PETs in these disorders not only has provided insights into the possible pathogenesis of sporadic PETs but also has presented several unique management and treatment issues, some of which are applicable to patients with sporadic PETs. Therefore, the study of PETs in these uncommon disorders has provided valuable insights that, in many cases, are applicable to the general group of patients with sporadic PETs. In this article, these areas are reviewed briefly along with the current state of knowledge of the PETs in these disorders, and the controversies that exist in their management are summarized briefly and discussed.

Is laparoscopic resection adequate in patients with neuroendocrine pancreatic tumors?

Since the first reports with laparoscopic resection of islet cell tumors in 1996, the experience worldwide is still limited, with only short-term outcomes available. Some have suggested that a malignant tumor is a contraindication to laparoscopic resection. Aim The aim of this study was to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with functioning, nonfunctioning, or overt malignant pancreatic neuroendocrine tumor (PNT). To our knowledge this is the largest single-institution series on this subject to date. Patients and methods A total of 49 consecutive patients (43 women, 6 men; mean age 58 years, range 22-83 years) underwent laparoscopic pancreatic surgery (LPS) from April 1998 to June 2007. Preoperative localization was done by computed tomography, magnetic resonance imaging, endoscopic ultrasonography, and Octreoscan imaging. Other than 9 PNTs localized in the head of the pancreas, all tumors were located in the left pancreas. Malignancy was diagnosed based on the presence of lymph nodes or liver metastasis. There were 33 patients with functioning tumors: 4 with gastrinomas (mean size 1.2 cm), 1 with a glucagonoma (4 cm), 3 with vipomas (3.2 cm), 2 with carcinoids (5.2 cm), 20 with sporadic insulinomas (1.4 cm), 2 with insulinoma/multiple endocrine neoplasia type 1 (MEN-1) (4.4 cm), and 1 with a malignant insulinoma (13 cm). Sixteen patients had a nonfunctioning tumor (mean size 5 cm). The following techniques were performed: laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP), laparoscopic distal pancreatectomy with splenectomy (Lap SxDP) and laparoscopic enucleation (Lap En)/laparoscopic excision (Lap E). Lymph node dissection was performed when malignancy was suspected (Strasberg s technique). Evaluation criteria included operative and postoperative factors, pathologic data including R0 or R1 resection (the pancreatic transection margin and all transection margins on the specimen were inked). Long-term outcomes were analyzed by tumor recurrence and patient survival. Results Four cases (8.2%) were converted to open surgery. Overall, Lap SPDP, Lap SxDP, and Lap En/Lap E were performed in 15 (33.3%), 8 (17.8%), and 22 (48.9%) patients, respectively. The operative time and blood loss was significantly lower in the Lap En group compared with the other laparoscopic techniques. The group of patients with malignant tumors undergoing Lap SxDP had a longer operating time and greater blood loss compared with the other distal pancreatectomy (Lap DP) techniques. Overall, the postoperative complications were significantly higher in the Lap En group (42.8%) than in the Lap DP (Lap SPDP+Lap SxDP) group (22%). These complications were mainly pancreatic fistula: 8.7% after Lap DP and 38% after Lap En. The overall morbidity was significantly higher after Lap SPDP (26.7%) than after Lap SxDP (12.5%) owing to the occurrence of splenic complications in the Lap SPDP group without splenic vessel preservation two of seven (28.5%). The means and ranges of hospital stay after Lap SPDP, Lap SxDP, and Lap En/Lap E were 5.9 (5-14), 7.5 (5-12), and 5.5 (5-7) days, respectively (NS). Pathology examination of the specimen showed R0 resection in all patients with malignant PNT. The mean time to resumption of previous activities for patients undergoing Lap DP or Lap En was 3 weeks. There were no postoperative (30 days) or hospital deaths. Conclusions This series demonstrates that LPS is feasible and safe in benign-appearing and malignant neuroendocrine pancreatic tumors (NEPTs). The benefits of minimally invasive surgery were manifest in the short hospital stay and acceptable pancreas-related complications in high-risk patients. LPS can achieve negative tangential margins in a high percentage of patients with malignant tumors. Although surgical cure is rare in malignant NEPTs, significant long-term palliation can be achieved in a large proportion of patients with an aggressive surgical approach.

Localisation and staging of gastrin producing tumours using cross-sectional imaging modalities

Cross sectional imaging in the assessment of gastrinomas has three major applications: Tumor localization (sporadic gastrinoma, MEN I) in patients undergoing primary or secondary surgery. Staging of metastasized tumors, especially assessment of lymph nodes and liver metastases, possibly including a risk analysis prior to liver resection. Post-surgery follow-up and monitoring of bio- or chemotherapy. Detection of primary tumors is strongly correlated with their size. However, the sensitivity of surgical assessment of the mostly small tumors by experienced surgeons is much higher than that of any imaging modality. Of all imaging modalities, endoultrasonography (EUS) followed by Somatostatin receptor scintigraphy (SRS) is the most sensitive modality for the assessment of pancreatic tumors in asymptomatic patients suffering from a MEN-I syndrome. Scintigraphy has the highest sensitivity in tumors of symptomatic patients and in the assessment of metastases. CT and MRI are only second line diagnostic modalities. Their sensitivity is largely dependent on the selection of patients. As a potential application, 3D reconstruction of nearly isotropic CT data sets for the risk assessment prior to liver resection is currently developing. Due to the absent radiation exposure, MRI is increasingly utilized to monitor the response of metastases under systemic therapy, e.g. in clinical trials.

Surgical aspects of gastrinoma in multiple endocrine neoplasia type 1

Gastrinoma is the most frequent functional pancreaticoduodenal endocrine tumor in patients with multiple endocrine neoplasia type 1 (MEN1) and one major determinant of mortality in this syndrome. Whether routine surgical exploration should be performed in a patient with MEN1 associated Zollinger-Ellison syndrome (ZES) to possibly reduce the malignant spread and eventually increase survival still remains controversial. There is not only disagreement about the indication for surgical exploration, but also what type of procedure should be performed, since sufficient evidence-based data are not available. The article discusses the available data on treatment strategies of MEN1 associated ZES.

Management of sporadic and multiple endocrine neoplasia type 1 gastrinomas

BACKGROUND

Gastrinomas are functional endocrine duodenopancreatic tumours and are responsible for Zollinger-Ellison syndrome (ZES). Clinical presentation, localization techniques and operative management were reviewed.

METHODS

An electronic search of the Medline database was undertaken for articles published in English between January 1987 and May 2007. This timeframe was chosen because of the fundamental changes in operative strategy, antisecretory therapy and localization techniques during this period.

RESULTS AND CONCLUSION

Most gastrinomas are located in the 'gastrinoma triangle', comprising the head of the pancreas, and the first and second parts of the duodenum. Some 20 per cent of gastrinomas occur in association with multiple endocrine neoplasia type 1 (MEN1) and 50-60 per cent of tumours are malignant at the time of diagnosis. Biochemical evidence justifies operation of which duodenotomy is an essential part. Only complete tumour resection allows 5- and 10-year survival rates of 90 per cent. Pylorus-preserving pancreaticoduodenectomy may be the procedure of choice for MEN1-ZES.

Canine gastrinoma: a case study and literature review of therapeutic options

CASE HISTORY

A 6.2 kg, 8-year-old, spayed female Australian Terrier was presented with weight loss, inappetence, lethargy and a 2-day history of intermittent vomiting.

CLINICAL FINDINGS

The dog had cranial abdominal pain and there was melaena present on digital rectal examination. Haematology revealed a marked, acute leucogram.

DIAGNOSIS AND TREATMENT

Fasting serum gastrin levels were markedly elevated and gastrinoma was suspected. Treatment was initiated with omeprazole, ranitidine and sucralfate. The dog remained clinically normal for 26 months, at which time exploratory surgery was undertaken and the dog subsequently euthanised due to extensive metastases. Histopathology and immunocytochemistry confirmed the diagnosis of metastatic gastrinoma.

CLINICAL RELEVANCE

This is a rare condition infrequently reported. Although the number of cases treated with omeprazole are too few to draw firm conclusions, it would appear that proton pump inhibitors are useful and should be considered for cases of gastrinoma managed medically. Long-term prognosis is poor, and survival times range from 1 to 147 weeks. Many treatment options are discussed in the medical literature though not all are feasible in veterinary patients.

Gastrinoma: sporadic and familial disease

The physiologic sequelae of a gastrinoma can be well controlled with medical therapy. The role of surgery has shifted from managing acid hyper-secretion and ulcer complications to preventing metastatic disease and managing symptomatic metastases. With improved methods of imaging for the detection of occult gastrinomas, the prospective evaluation of the role for surgery in altering the natural history of these tumors is now possible.

Avaliação dos insulinomas pela ultra-sonografia intra-operatória: estado atual do tema

Os autores fazem uma revisão da literatura sobre a utilização da ultra-sonografia intra-operatória para a avaliação dos insulinomas pancreáticos. São referidos os resultados da ultra-sonografia intra-operatória, ultra-sonografia e tomografia computadorizada realizadas no pré-operatório, e os resultados da inspeção e palpação do pâncreas realizadas durante procedimentos cirúrgicos referidos na literatura.

[Zollinger-Ellison syndrome]

The preoperative localization of gastrinomas often fails despite all modern imaging methods. Therefore, after biochemical confirmation of the diagnosis and exclusion of diffuse metastases, a meticulous surgical exploration including intraoperative ultrasound (IOUS) and duodenal exploration after duodenotomy should be performed. The experienced surgeon will be able to identify more than 90% of the primary tumors. Depending on the localization, excision of the tumor in the duodenal wall or enucleation from the pancreatic head should be performed. If the tumor is localized in the tail of the pancreas, distal pancreatectomy is the treatment of choice. Complete resection of the tumor is the only curative approach for the patients. For MEN-1 gastrinomas a spleen-preserving distal pancreatectomy with enucleation of tumors of the pancreatic head and duodenotomy with excision of duodenal gastrinomas should be performed. If the source of gastrin secretion can be regionalized to the pancreatic head by a preoperative SASI angiography, a pylorus-preserving partial pancreaticoduodenectomy might be the treatment of choice.

Endoscopic ultrasound in the localisation of pancreatic islet cell tumours

The role of endoscopic ultrasound (EUS) in the evaluation of entero-pancreatic endocrine tumours has evolved in conjunction with advances in other imaging methods. The high spatial resolution of this technique allows the detection of very small lesions and their precise anatomical localisation. In patients with biochemically proven insulinoma, EUS can be effectively used as a first line investigation, with a sensitivity of 94%. Combined with thin section CT, the sensitivity rises to 100%. There is also high sensitivity in diagnosing intrapancreatic gastrinomas but lower for those arising in the duodenal wall which require detailed duodenal evaluation at surgery. EUS in conjunction with Somatostatin Receptor Scanning (SRS) has a combined sensitivity of 93% for gastrinomas. EUS is recommended for screening of asymptomatic patients with genetically proven MEN1. There is a limited role for EUS guided biopsy in pancreatic endocrine tumours.

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.

The diagnosis and medical management of advanced neuroendocrine tumors

Neuroendocrine tumors (NETs) constitute a heterogeneous group of neoplasms that originate from endocrine glands such as the pituitary, the parathyroids, and the (neuroendocrine) adrenal, as well as endocrine islets within glandular tissue (thyroid or pancreatic) and cells dispersed between exocrine cells, such as endocrine cells of the digestive (gastroenteropancreatic) and respiratory tracts. Conventionally, NETs may present with a wide variety of functional or nonfunctional endocrine syndromes and may be familial and have other associated tumors. Assessment of specific or general tumor markers offers high sensitivity in establishing the diagnosis and can also have prognostic significance. Imaging modalities include endoscopic ultrasonography, computed tomography and magnetic resonance imaging, and particularly, scintigraphy with somatostatin analogs and metaiodobenzylguanidine. Successful treatment of disseminated NETs requires a multimodal approach; radical tumor surgery may be curative but is rarely possible. Well-differentiated and slow-growing gastroenteropancreatic tumors should be treated with somatostatin analogs or alpha-interferon, with chemotherapy being reserved for poorly differentiated and progressive tumors. Therapy with radionuclides may be used for tumors exhibiting uptake to a diagnostic scan, either after surgery to eradicate microscopic residual disease or later if conventional treatment or biotherapy fails. Maintenance of the quality of life should be a priority, particularly because patients with disseminated disease may experience prolonged survival.

The analysis of immunophenotype of gastrin-producing tumors of the pancreas and gastrointestinal tract

BACKGROUND

Gastrinomas are located more frequently in the pancreas, which normally has no cells that can produce gastrin. They have a more aggressive course than other pancreatic endocrine tumors and extrapancreatic gastrinomas associated with multiple endocrine neoplasia Type 1 syndrome. The current study analyzed immunophenotypes of gastrinomas and compared them with other pancreatic endocrine tumors.

METHODS

Twenty-one formalin-fixed, paraffin-embedded specimens (15-tumors in the pancreas, 1 in the duodenum, 1 in the stomach, 1 in the liver, and 3 of unknown primary location) accompanied by Zollinger-Ellison syndrome and 17 other pancreatic endocrine tumor specimens were investigated. They were stained immunohistochemically for gastrin, chromogranin A, synaptophysin, insulin, glucagon, somatostatin, pancreatic polypeptide, calcitonin, serotonin, chorionic gonadotropin, adrenocorticotropic hormone, carcinoembryonic antigen, epithelial membrane antigen, and cytokeratin 19.

RESULTS

Gastrinomas coexpressed neuroendocrine and exocrine markers, including chromogranin A, synaptophysin, carcinoembryonic antigen, cytokeratin 19, and epithelial membrane antigen. Carcinoembryonic antigen was found in all 17 gastrinomas (100%), cytokeratin 19 was found in 15 of 17 (88.2%) gastrinomas, and epithelial membrane antigen was found in 16 of 18 (88.9 %) gastrinomas. Cytokeratin 19, epithelial membrane antigen, and carcinoembryonic antigen were not found to be present in the pancreatic endocrine tumors, but chromogranin A and synaptophysin were. Chorionic gonadotropin was found in 16 gastrinomas (100%), but only in 2 of 17 other pancreatic endocrine tumors (11.8 %).

CONCLUSIONS

Pancreatic gastrinomas were characterized by the coexpression of neuroendocrine markers, exocrine markers, and chorionic gonadotropin. Therefore, pancreatic gastrinomas made a special intermediate group of tumors, which phenotypically combined features of neuroendocrine and exocrine neoplasms. These findings suggested that sporadic pancreatic gastrinomas and other pancreatic endocrine tumors are different phenotypically and are possibly of different origin.

Current surgical management of Zollinger-Ellison syndrome (ZES) in patients without multiple endocrine neoplasia-type 1 (MEN1)

The role of surgery in the management of patients with sporadic (not part of multiple endocrine neoplasia type 1) Zollinger-Ellison syndrome (ZES) is controversial. In this setting, 60-90% of gastrinomas are malignant and medical therapy can control the gastric acid hypersecretion in virtually every patient. Therefore, the progression of tumor is the major determinant of survival. Surgery will cure approximately one-third of patients with sporadic ZES. It will decrease the development of liver metastases and may improve survival. Somatostatin receptor scintigraphy is the best preoperative localization study. Its results are as good as all other imaging studies combined. Operative techniques should always include duodenotomy (opening the duodenum) and meticulous dissection of lymph nodes in the gastrinoma triangle, because duodenal primary tumors are often missed and lymph node primary tumors or metastases are common. Postoperative evaluation should include secretin test because it is the most sensitive method to document cure and detect tumor recurrence.

Management and outcome of patients with sporadic gastrinoma arising in the duodenum

BACKGROUND

Primary duodenal gastrinomas are now recognized as a common etiology for patients with sporadic Zollinger Ellison Syndrome (ZES); however, the clinical and pathologic features of this condition and long-term outcome after operation are not well characterized.

METHODS

Between November 1982 and September 2000, 63 patients diagnosed with sporadic ZES underwent resection of a primary duodenal gastrinoma and regional nodal metastases with curative intent. Data from a prospectively maintained database were reviewed for clinical and pathologic parameters relating to primary tumor size, location, frequency of lymph node metastases, and disease-specific and disease-free survival.

RESULTS

There were 41 males and 22 females (mean age, 48.6 years). The majority of duodenal gastrinomas were in the first or second portions of the duodenum (83%). Tumor size ranged from 0.2 to 2.0 cm with 62% measuring less than 1.0 cm. Sixty percent of individuals had regional lymph node metastases identified primarily in proximity to the primary tumor. At a median 10-year follow-up, the overall disease-specific and disease-free survivals were 100% and 60%, respectively. Actuarial 10-year disease-free survival was significantly higher for patients without lymph node metastases versus those with lymph node metastases (78% versus 48%, P = 0.0137).

CONCLUSIONS

Duodenal gastrinomas in patients with sporadic ZES are frequently small, most commonly located in the proximal duodenum, and associated with regional lymph node metastases in 60%. Disease-free survival is lower for patients with regional lymph node metastases suggesting that a more systematic lymphadenectomy to extirpate occult disease may be indicated in this group.

Somatostatin analogues in the treatment of endocrine tumors of the gastrointestinal tract

Somatostatin and its long-acting analogues have been introduced for the treatment of endocrine tumours of the gastrointestinal tract as they have been shown to effectively control symptoms resulting from excessive hormone release in patients with carcinoid, Verner-Morrison and glucagonoma syndromes. This beneficial effect is due to the presence of somatostatin receptors in high densities on the majority of endocrine tumours. The symptomatic effect is less pronounced in insulinomas, since 30 - 50% of these tumours lack or express only a few somatostatin receptors. With respect to symptomatic control, somatostatin receptor subtypes 2 and 5 are the most important and the currently available long-acting analogues octreotide and lanreotide bind preferentially to these receptor subtypes. Long-term studies have shown that somatostatin analogues are safe and that the most important adverse advent is the development of gallstones. The antiproliferative potency of somatostatin and its analogues in vitro and in experimental tumour models prompted a number of studies in patients with metastatic endocrine tumours that are generally unresponsive to conventional chemotherapeutic protocols. Stabilisation of tumour growth lasting for months to a few years was the most favourable result, occurring in 30 - 70% of patients. However, definite proof of antiproliferative potency in man is still pending since placebo-controlled studies are not available. Radioligand therapy based on 111Indium, 90Yttrium and 177Lutetium coupled to somatostatin analogues via bifunctional chelators is currently under investigation with promising data concerning long-lasting control of symptoms and tumour growth from Phase I trials.

Gastrinoma

Gastrinoma treatment has evolved considerably in the last 20 years. In particular, the advent of effective acid-reducing pharmacologic agents has changed the primary morbidity of this disease entity from one of acid hypersecretion to one of tumor growth and spread. Thus, while symptoms can be temporized using histamine receptor antagonists, proton pump inhibitors, or somatostatin analogs, cure can be effected only by surgical means. Recent advances in operative techniques and pre- and intra-operative imaging studies, including routine duodenotomy, somatostatin-receptor scintigraphy, and intraoperative ultrasound, have allowed for identification and subsequent resection of more than 95% of gastrinoma tumors. Most experts agree that all sporadic cases of localized gastrinoma should be excised. In addition, debulking of metastatic tumor may improve symptoms and survival when cure cannot be ascertained. There is, however, some controversy as to the surgical approach for gastrinoma found in the setting of multiple endocrine neoplasia, type 1. Because of the usual multiplicity and particular indolence of these tumors, two primary strategies have emerged: aggressive approaches have been advocated in an effort to eradicate all present and potential tumor; and less aggressive, or nonoperative, approaches have been suggested because it is unclear whether intervention offers survival or disease-free benefit in this population. We advocate surgical intervention for patients with gastrinoma and multiple endocrine neoplasia, type 1 when tumors exceed 2.5 cm in size. This tumor size has been associated with a higher likelihood of hepatic metastases, which ultimately affects survival. The role of adjuvant therapies for gastrinoma remains limited.

Primary nodal gastrinomas

BACKGROUND

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

DESIGN

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

RESULTS

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

CONCLUSION

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