Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Somatostatin (SRIF) receptors (sst) are present on normal pancreatic endocrine beta-cells. However, the use of SRIF analogs in the scintigraphic imaging of insulinomas and in the medical management of these tumors seems to be restricted to a subgroup of patients. The aim of this study was to determine the prevalence of sst expression in vitro and characterize sst subtype binding in insulinomas and its correlation with in vivo sst receptor scintigraphy (SRS). In vitro studies were performed on 27 insulinomas from 25 patients: 22 with benign and three with malignant tumors. Semiquantitative RT-PCR of sst mRNAs was performed for 20 of these insulinomas. Sst2 and sst5 were expressed in 70%, sst1 in 50%, and sst3 and sst4 subtypes only in 15-20% of the tumors. (125)I-Tyr(0)DTrp(8)SRIF(14) binding was assessed by quantitative autoradiography in 18 insulinomas, and competition experiments were performed with SRIF(14) and L797-591, L779-976, L796-778, L803-087, L817-818, selective agonists of the five sst subtypes, and BIM23244, a selective agonist of sst2 and sst5. Significant specific binding was observed in 72% of the insulinomas. Displacement experiments with ligands of higher affinity for each of the sst receptors revealed significant binding with the sst2 and sst5 ligands in 72%, sst3 in 44%, sst1 in 44%, and sst4 in 28% of cases. All insulinomas displaying sst2 binding were also sst5 sensitive. However, the ratio of sst5/sst2 displacement was variable and only equal to that for SRIF(14) in experiments with the sst2/sst5 agonist BIM23244. SRS was performed 10 times in nine patients; it detected 60% of the tumors, including metastases of a malignant insulinoma. All the tumors detected by SRS displayed high levels of (125)I-Tyr(0)DTrp(8)SRIF(14) binding. The mechanisms underlying the loss of expression of sst2/sst5 in a third of insulinomas remains to be determined, but this loss of expression may be involved in beta-cell dysfunction.
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PMID:Somatostatin receptors 2 and 5 are the major somatostatin receptors in insulinomas: an in vivo and in vitro study. 1460 73

Differential diagnosis of hypoglycemic patients should include insulinoma. Plasma insulin-to-glucose ratio greater than 0.3 or C-peptide levels of 2 nmol/L or greater suggest insulinoma. Abdominal CT scan can exclude metastatic disease and identify uncommonly large islet cell tumors, but has poor sensitivity for localizing insulinomas; transgastric endoscopic ultrasound is the most sensitive technique. Palpation combined with intraoperative ultrasound identifies most tumors at operation and gives vital information about surrounding structures. If no tumor is found, blind distal pancreatectomy should not be performed, and the patient should be referred to an endocrinologist or endocrine surgeon for diagnostic confirmation and further localization. Laparoscopy is a viable alternative to open tumor resection; laparoscopic ultrasound can facilitate localization and guide safe resection.
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PMID:Surgical treatment of insulinomas. 1514 34

About 25% of patients with ZES have MEN 1. Except diarrhoea, less frequent in patients with ZES-MEN 1 than in sporadic ZES, and specific MEN 1-related signs, clinical characteristics are similar in both ZES types. Acid output and gastrin levels are also similar whether in the basal state or after secretin stimulation. Primary hyperparathyroidism (PHPT) exists in the majority of ZES-MEN 1 patients, 30% have pituitary adenoma (prolactinomas for half), 30% adrenal involvement, 25 to 30% have EC-Lomas; bronchial and thymic carcinoids have probably been underevaluated. Gastrinomas are multiple predominantly located in the duodenal wall, but also in the pancreas in association with clinically silent endocrine tumors. The spread of the disease: metastases to the liver (LM), mediastinum, bones, is evaluated at best by Octreoscan. Endoscopic ultrasonography evaluates the number, size and anatomical characteristics of gastrinomas. Patients without LM have an excellent prognosis. Surgery never cures ZES, but is necessary in case of associated life-threatening condition such as insulinoma and has been advocated to prevent LM development in patients with large pancreatic tumor(s). However although, indeed, the size of the tumor, when located in the pancreas > 3 cm, favours metachronous LM occurrence, surgery, in our experience, has not been able to prevent LM development. Hepatic malignancies remain however the most pejorative prognostic determinant for survival and raise the most difficult therapeutic challenge. Surgery is the best option whenever feasible; specific chemotherapy and chemo-embolisation have not conclusively achieved definite successes. Long-term octreotide treatment, however, has been shown recently to obtain tumour stabilisation. Internal irradiation with 90 Ytrium-labelled octreotide is a new promising option, presently under evaluation (Novartis European trial). Preliminary results are promising.
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PMID:[Diagnostic and therapeutic strategies in Zollinger-Ellison syndrome associated with multiple endocrine neoplasia type I (MEN-I): experience of the Zollinger-Ellison Syndrome Research Group: Bichat 1958-1999]. 1514 2

Endocrine surgeons should maintain a high index of suspicion when patients are diagnosed with clinical signs or symptoms of parathyroid carcinoma. Although rare, the best chance for cure of these patients is at the time of the initial operation. Surgical resection of recurrent disease can provide effective palliation and can sometimes be assisted using gamma-probe directed dissection of sestamibi-labeled tumor tissue. Treatment of hyperparathyroidism in the setting of multiple endocrine neoplasia type 1 (MEN-1), particularly in the reoperative setting, can be aided by using the rapid intraoperative parathyroid hormone assay to judge the adequacy of parathyroid debulking. In addition, in selected cases, the gamma probe can assist in identifying the location of ectopic or autografted sestamibi-labeled parathyroid tissue. Patients with incidental adrenal masses rarely require fine needle aspiration to exclude metastatic cancer. Fine needle aspiration, if performed, should never precede hormone evaluation to exclude pheochromocytoma. Patients who are diagnosed with incidental adrenal masses in the setting of a prior or concurrent cancer diagnosis are equally likely to have a primary adrenal mass as they would be to have metastatic cancer in the adrenal gland. Pheochromocytomas occasionally develop in patients with MEN-1. In suspicious cases, molecular identification of an MEN-1 mutation can be used to confirm the diagnosis. Preoperative hormone evaluation of a patient with an adrenal incidentaloma should include evaluation for subclinical Cushing's syndrome through an overnight 1-mg dexamethasone suppression test. Identification of this condition allows for safe peri- and postoperative steroid hormone replacement, with very slow withdrawal of exogenous steroids to allow the opposite adrenal gland to recover and avoid postoperative Addisonian crisis. Paragangliomas are more commonly multifocal and malignant compared to pheochromocytomas. Evaluation of patients with paragangliomas should include radiographic staging for multifocality and metastatic disease, and postoperative hormone and radiographic follow-up evaluation should be performed. Consideration should be given to genetic testing for von Hippel-Lindau and succinate dehydrogenase mutations. Surgical treatment of rare functioning pancreatic and duodenal endocrine tumors, such as metastatic sporadic insulinoma and MEN-1-associated gastrinoma, can provide effective palliation. Surgical treatment should be integrated into a comprehensive treatment scheme that recognizes the natural history of the disease and incorporates appropriate adjunctive therapies and follow-up strategies.
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PMID:Unusual functioning endocrine tumors. 1523 9

All pancreatic neuroendocrine tumors derive from Langerhans islet cells and have a low incidence. Half of them are functioning tumors that produce diverse hormones and occasionally cause serious clinical endocrine syndromes. They may be malignant, but they have a better survival, if compared to pancreatic ductal adenocarcinoma. Insulinoma, gastrinoma, glucagonoma, VIPoma (VIP=vasoactive intestinal peptide), somatostatinoma and ACTHoma are functioning tumors and they may also be part of Multiple Endocrine Neoplasia type I (MEN 1) syndrome and of von Hippel-Lindau disease. Diagnosis of non-functioning tumors is usually late, when they reach a big size and have even developed nodal and hepatic metastases. Nowadays, there are effective medical treatments for the medical problems secondary to excessive hormone production. For example, the hypergastrinemia typical of the Zollinger-Ellison syndrome in gastrinoma, can be adequately managed. Surgical resection is the most advisable therapy for pancreatic endocrine tumors, especially when they are small, when long time survival is better. Pre and intra operative imagenology is a great aid to locate these tumors. There are several surgical alternatives, according to the tumor size and location within the pancreas. Furthermore, palliative therapy can be used in disseminated disease. Treatment success is the result of a multidisciplinary medical team work of endocrinologists, surgeons, gastroenterologists, pathologists and geneticists.
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PMID:[Pancreatic neuroendocrine tumors]. 1527 51

More than 90% of insulinomas are benign tumors. Insulinomas cause hypoglycemia and thereby symptoms of neuroglycopenia and catecholamine response. During symptoms, blood glucose levels should be less than 40 mg/dl (less than 2.2 mmol/l), concomitant insulin levels should be > or =6 IU/ml (> or =43 pmol/l) and concomitant C-peptide levels > or =0.2 pmol/l. Most insulinomas can be identified intraoperatively by experienced surgeons. Initial therapy consists of administration of frequent meals and/or by glucose infusion. In patients with solitary insulinomas, complete surgical removal of the tumor should be the primary goal. In patients with metastatic insulinomas, symptoms of insulin hypersecretion will only completely disappear after complete resection of all metastases.
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PMID:Insulinoma. 1547 11

An insulinoma is a rare pancreatic endocrine tumor that is typically sporadic, solitary, and less than 2 cm in diameter. Fewer than 5% of insulinomas are larger than 3 cm. Ninety percent or more of all insulinomas are benign. Larger tumors are more likely to be malignant. We report a case of a giant pedunculated insulinoma, measuring 9 cm in diameter and weighing 100 g, with amyloid deposits accounting for 70% of the tumor volume. At the time of operation, no local invasion or metastatic disease was identified. On pathological evaluation, the tumor was classified as an insulinoma of uncertain biological behavior. In addition to describing the clinical presentation and operative findings, criteria for determining malignancy are outlined, a detailed pathological description is presented, and the 2000 World Health Organization Classification for Pancreatic Endocrine Neoplasms is reviewed.
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PMID:Giant insulinoma: case report and review of the literature. 1552 39

Accurate preoperative detection, localization, and staging of the primary tumor and metastases are essential for the selection of appropriate candidates for surgery. In dogs with insulinoma, preoperative assessment usually is performed with transabdominal ultrasonography (US). There are no reports on the use of computed tomography (CT) for this purpose. The preoperative use of somatostatin receptor scintigraphy (SRS) recently has been advocated for the identification of insulinoma and gastrinoma in dogs, but its accuracy remains to be established. In this report US, CT, and single-photon emission computed tomography (SPECT) with [111In-DTPA-D-Phe1]-octreotide (a specific form of SRS) were compared for their effectiveness in detecting and localizing primary and metastatic insulinoma in dogs. Findings at surgery or postmortem examination served as control. Of 14 primary insulinomas, 5, 10, and 6 were correctly identified by US, CT, and SPECT, respectively. No lymph node metastases were detected by US or SPECT. CT identified 2 of 5 lymph node metastases but also identified 28 false-positive lesions. Two of 4 livers were found to be positive for metastases by 1 of the imaging techniques. US can be used for the initial evaluation of dogs with hypoglycemia. Although CT identifies most primary tumors, intraoperative inspection and palpation of the pancreas is still superior. SPECT appears as effective as US and CT in detecting insulinomas. Future developments in preoperative imaging techniques might improve current methods of canine insulinoma detection.
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PMID:Comparison of ultrasonography, computed tomography, and single-photon emission computed tomography for the detection and localization of canine insulinoma. 1571 42

Although neuroendocrine tumors of the pancreas are traditionally managed by laparotomy, these rare neoplasms may be amenable to laparoscopic surgical resection. We present our experience with laparoscopic distal pancreatectomy in two such patients, and discuss the operative technique with emphasis on organ preservation. Two female patients aged 63 and 69 years presented with clinical and biochemical features of an insulinoma and a vasoactive intestinal peptide secreting tumor (VIPoma), and were found on cross-sectional imaging to have 1.2-cm and 4.5-cm solitary tumors in the tail of the pancreas. They underwent laparoscopic distal pancreatectomy with and without preservation of splenic vessels and spleen respectively. Both procedures were completed laparoscopically. The operating time was 180 and 210 minutes respectively. There were no postoperative complications. The postoperative hospital stay was 4 and 14 days respectively. Histology revealed a benign insulinoma and a malignant VIPoma with lymph node metastases respectively. Laparoscopic distal pancreatectomy for neuroendocrine tumors of the pancreas may be accomplished safely, with preservation of the spleen and splenic vessels in benign disease, and with benefits to the patients in terms of postoperative recovery.
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PMID:Laparoscopic distal pancreatectomy for neuroendocrine tumors of the pancreas. 1581 91

The rarity of malignant insulinoma limits reports on therapeutic strategies and outcome. The treatment and follow-up of 10 patients, all presenting an insulinoma with metastatic disease of the liver and newly diagnosed between 1992 and 2002, is reported. Pancreatic surgery with successful removal of the primary tumor preferentially located in the tail was performed in 7 women and 3 men, median age 55 years (range 36-82 years). If appropriate, 5 patients underwent additional hepatic surgery and lymph node resections. Liver metastases as the major cause of postoperatively persistent hypoglycemia were subsequently treated by repeated transarterial hepatic chemoembolization and chemoperfusion protocols using high-dose transhepatic streptozocin perfusions (3-4 g per session). The current median survival time for all 10 patients is 2.6 years (range: 1.6-9.7 years). Six patients are currently alive with a median survival of 3.7 years (1.7-9.7 years), five of them with stable disease and free of hypoglycemia. Four patients died after a median survival of 1.8 years (range: 1.6-7.5 years) from complications of unmanageable hypoglycemia. It is concluded that the necessity to treat debiliating and life-threatening hypoglycemia in metastatic malignant insulinoma warrants the option of radical endocrine surgery in combination with extended and repeated postoperative chemoembolization of liver metastases.
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PMID:Malignant metastatic insulinoma-postoperative treatment and follow-up. 1588 Feb 79


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