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)

The effects of octreotide in vivo and in vitro on hormone release, in vivo [123I]Tyr3-octreotide scanning, and in vitro [125I]Tyr3-octreotide autoradiography were compared in five patients with endocrine pancreatic tumors. [123I]Tyr3-octreotide scanning localized the primary tumor and/or previously unknown metastases in four of the five patients. The patient with a negative scan had an insulinoma that did not respond to octreotide in vivo. No Tyr3-octreotide-binding sites were subsequently found at autoradiography of the tumor, whereas somatostatin-14 receptors were present at a high density. In parallel, culture studies with the cells prepared from this adenoma showed that insulin release was not affected by octreotide, while both somatostatin-14 and -28 significantly suppressed hormone release. Culture studies of the tumor cells from two gastrinomas showed a dose-dependent inhibition of gastrin release by octreotide. Octreotide exerted direct antiproliferative effects in one of these gastrinomas, which had been shown to be rapidly growing in vivo. Both gastrinomas had specific somatostatin receptors, as measured by in vitro receptor autoradiography. Somatostatin release by the cultured somatostatinoma cells from one of these patients was suppressed by octreotide. In conclusion, 1) the [123I]Tyr3-octreotide scanning procedure is valuable in the localization of primary endocrine pancreatic tumors as well their often clinically not yet recognized metastases; 2) the in vitro detection of somatostatin receptors in those tumors that were also visualized in vivo after injection of [123I] Tyr3-octreotide indicates that the ligand binding to the tumor in vivo indeed represents binding to specific somatostatin receptors; and 3) the parallel between the presence of somatostatin receptors on tumors and in in vivo and in vitro effects of octreotide on hormonal release from these tumors indicate that a positive scan predicts a good suppressive effect of octreotide on hormonal hypersecretion by these tumors.
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PMID:Parallel in vivo and in vitro detection of functional somatostatin receptors in human endocrine pancreatic tumors: consequences with regard to diagnosis, localization, and therapy. 216 29

Because of its widespread distribution within the nervous system and gastroenteropancreatic (GEP) system, and its diverse physiological inhibitory actions on various gastrointestinal functions, including endocrine and exocrine secretion, motility, liver and splanchnic blood flow and absorption, native somatostatin has been viewed as a possible therapy for many diseases. However, its short duration of action and consequent limited clinical usefulness have been overcome with the availability of Sandostatin (octreotide, Sandoz Ltd), a long-acting, synthetic octapeptide analog of the naturally occurring hormone. Sandostatin represents a significant advance in the treatment of growth hormone (GH) and thyrotropin (TSH)-secreting pituitary tumors and GEP endocrine tumors (carcinoid tumor, VIPoma, glucagonoma, insulinoma, and gastrinoma). Preclinical in vitro and animal studies have shown the antineoplastic activity of the compound. Moreover, because of a possible direct effect on somatostatin receptor-positive endocrine tumor cells and an indirect effect whereby Sandostatin lowers GH, insulin-like growth factor type 1 (IGF-1), and numerous gastrointestinal peptides, Sandostatin may prove useful as an adjunctive therapy in cancer patients. In vivo labeling of somatostatin receptor-positive tumors with radiolabeled somatostatin analogs now allows localization of such tumors and their metastases. In addition, targeted irradiation of these tumors by beta particle-emitting isotopes attached to such somatostatin analogs may become possible. The use of Sandostatin in acute esophageal variceal bleeding, pancreatic pseudocysts, gastrointestinal, and pancreatic external fistulae, short bowel syndrome, dumping syndrome and acquired immunodeficiency syndrome (AIDS)-related refractory hypersecretory diarrhea has provided encouraging results.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Future medical prospects for Sandostatin. 220 87

To define the course of malignant pancreatic islet cell tumors, 20 patients seen over 14 years with these neoplasms were reviewed. The 12 men and 8 women ranged in age from 22 to 76 years, with a mean of 52. Seven functional tumors included three insulinomas, two glucagonomas, one gastrinoma, and one somatostatinoma. One insulinoma was associated with a multiple endocrine neoplasia type I (MEN-I) syndrome. The 13 patients with nonfunctioning tumors had abdominal pain (3), jaundice (2), and steatorrhea (2). Seven had a palpable abdominal mass. Diagnosis of malignancy was based on local invasion (4), distant metastases (15), or both (1). One patient had percutaneous biopsy of a hepatic metastasis. All others had laparotomy for diagnosis and/or treatment. Each patient had a single tumor except the patient with MEN-I syndromes, who had multiple tumors throughout the pancreas. The head was involved in seven patients, the body in seven, and the tail in five. Operations included six curative and three palliative resections, five biliary diversions (two with concomitant enteric bypass), and five biopsies. Palliative resections were done for hormonal or local symptoms such as gastrointestinal (GI) bleeding and pain. Multiple chemotherapeutic agents were used, but the best results were obtained with DTIC (50% response). Four patients had radiation for liver, brain, or bone metastasis, with some improvement. Of five patients who had curative resections, four are alive 15 to 144 months, with a mean of 75 months. One died six years after diagnosis. Of the remaining 15 patients who had liver metastasis, seven patients are alive 8 to 168 months later, with a mean of 87 months.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Islet cell carcinoma of the pancreas. 254 52

Eighteen cases of insulinoma treated at the Instituto Nacional de la Nutricion in Mexico City are presented. The cases were operated on between 1959 and 1988, and include 10 women and 8 men with a mean age of 38. The duration of symptoms ranged between 4 and 96 months with a median of 27; 78% of the patients had neuropsychiatric symptoms, 61% seizures, and 55% loss of consciousness. One of the patients had evidence of type I multiple endocrine neoplasia. Diagnosis was established in all the patients with the demonstration of Whipple's triad and also with an elevated insulin determination in the last nine patients. In six cases the insulinoma was enucleated; in two a Whipple procedure was performed; in nine a distal pancreatectomy and in the remaining patient only resection of hepatic metastases; 67% of the tumors were diagnosed as benign solitary adenomas, 16.5% as carcinomas and the same number as hyperplasia. Operative mortality was 5.5%, and morbidity 44%. The three carcinomas survived 6, 8 and 36 months. Disappearance of the hypoglycemic symptoms was obtained in 93% of the cases of adenoma and hyperplasia.
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PMID:[Surgical treatment of insulinoma. Experience at the Salvador Zubiran National Nutrition Institute]. 255 Oct 25

Endocrine tumors of the pancreas are rare disorders that can cause life-threatening symptoms related to the excessive hormonal secretion and the malignant nature of the neoplasm. In addition, these neoplasms can present as part of familial endocrinopathy syndromes, especially multiple endocrine neoplasia type 1 (MEN-1). The initial step in evaluation of a patient with an islet cell tumor is definitive diagnosis of the hormonal syndrome that usually can be achieved biochemically. The next step is to reverse the life-threatening hormonal syndrome medically to allow radiographic localization of the islet cell neoplasm and to prepare the patient for elective surgery. In general, the goal of surgery is to accurately stage the extent of disease and to totally resect the tumor resulting in complete correction of the excessive hormonal condition and freedom from malignant progression of the tumor. Resection of the neoplasm should encompass metastatic disease in select individuals in whom complete or nearly complete resection can be achieved. Surgery must be performed with acceptable morbidity and mortality because the medical management of the excessive hormonal secretion in most patients is adequate and the progression rate of malignant islet cell carcinomas is usually slow. Patients with MEN-1 should be identified during evaluation by careful history and should be managed differently. These patients always have multiple islet cell tumors and may have malignant islet cell carcinomas. Large (3 cm) imageable pancreatic neoplasms in patients with MEN-1 should be resected because nearly 50 per cent are malignant. Zollinger-Ellison syndrome in patients with MEN-1 and primary hyperparathyroidism is best managed initially by surgery directed at the hyperparathyroidism. It may be impossible to correct the biochemical abnormalities of Zollinger-Ellison syndrome by islet cell tumor resection in patients with MEN-1. However, insulinoma or VIPoma syndromes can often be corrected by islet cell tumor resection. Portal venous sampling for hormones may be helpful in determining what hormone a specific tumor is secreting.
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PMID:The role of surgery in the management of islet cell tumors. 255 34

The radiological diagnosis and interventional management of neuroendocrine tumours of the gastrointestinal tract and pancreas are challenging, demanding the complete gamut of available resources. Carcinoid tumours are most commonly found in the appendix and small bowel. Barium studies usually disclose a small solitary mucosal or submucosal mass in the distal ileum at times associated with smooth muscle hypertrophy and thickening of the mucosal folds. Intussusception and bowel obstruction may be the presenting finding. Mesenteric involvement may evoke a desmoplastic reaction with rigidity, fixation, angulation and tethering of small bowel loops. Angiography may demonstrate a hypervascular primary neoplasm but more frequently reveals vascular encasement and distortion from the mesenteric desmoplastic reaction. Pancreatic islet cell tumour is best defined radiologically by angiography and computed tomography as a well circumscribed hypervascular mass which enhances with contrast material. Portal venous sampling is of considerable assistance in localizing insulinoma. Metastases from neuroendocrine tumours to lymph nodes and to the liver are usually hypervascular. In the evaluation of the liver by CT scanning prior to contrast as well as dynamic scanning during the bolus intravenous injection of contrast material are necessary. At times the precontrast scan is more revealing. Computed tomography with the catheter in the superior mesenteric artery followed by selective hepatic arteriography is the most accurate combination for the detection of hepatic metastases. Interventional radiological management by sequential hepatic arterial embolization is the treatment of choice for multiple hepatic metastases from neuroendocrine tumours. Thus far, the maximum number of embolic episodes in a single patient has been 13. The carcinoid syndrome has been controlled in 87% while 79% of islet cell tumour hepatic metastases have responded. Contraindications to HAE includes a combination of all of the following: (i) replacement of more than 50% of the liver by tumour, (ii) serum lactic dehydrogenase above 425 mU/ml, (iii) serum glutamic oxaloacetic transaminase above 100 mU/ml, and (iv) bilirubin above 2 mg/dl. In the face of occlusion of the portal vein by intravascular neoplasm, HAE is contraindicated only if portal flow through collateral vein is away from the liver.
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PMID:Gastrointestinal and pancreatic endocrine tumours. 267 21

Fourteen hormone-producing gastrointestinal tract tumors were tested for their content of somatostatin (SRIH) receptors, using receptor autoradiography and in vitro binding assay with tumor homogenates. All four gastrinomas tested had high levels of SRIH receptors, as did two of five insulinomas and four of five vasoactive intestinal peptide-producing tumors. Receptor visualization was obtained with two different radioligands, either a SRIH-28 analog, [125I]-[Leu8,D-Trp22,Tyr25]SRIH-28, or a SRIH octapeptide, the [125I]Tyr3 derivative of SMS 201-995 [H-DPhe-Cys-Phe-DTrp-Lys-Thr-Cys-Thr(ol)], [125I]204-090. In both cases receptors were localized over the tumor cell area only. Biochemical and pharmacological analyses of one insulinoma and two vipomas revealed saturable, high affinity binding sites with pharmacological specificity for SRIH. However, differences in receptor affinity of selected SRIH analogs, in particular SRIH-28 and SRIH octapeptides, were found between the insulinomas and the two other tumor types, vipoma and gastrinoma. The presence of SRIH receptors on various hormone-producing gastrointestinal tumors suggests that at least part of the beneficial effects of chronic therapy with SRIH analogs may be mediated through such membrane-bound receptors located on the tumor itself. SRIH receptor measurement may be of prognostic value in assessment of the therapeutic efficacy of SRIH analogs. They may also be of diagnostic value, if used as in vivo markers for the localization of small hormone-producing gastrointestinal tumors or their metastases.
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PMID:Hormone-producing gastrointestinal tumors contain a high density of somatostatin receptors. 282 49

The potential for malignancy of an islet cell tumor of the pancreas is difficult to cytologically judge when one evaluates only the primary lesion, because a malignant condition is usually determined by the presence of regional or distant metastases. Nuclear DNA cytometric measurements have proved helpful both in the evaluation of the malignant potential of other endocrine and nonendocrine lesions and in the determination of the "aggressiveness" of these tumors. Thirty-six islet cell tumors or their metastases from 25 patients were studied. Eleven patients had insulinomas and typical insulinoma syndromes, and 14 others had gastrinomas with the Zollinger-Ellison syndrome. Tissue from each tumor was stained by the Feulgen technique, and nuclear DNA cytometry was performed by means of the microTICAS system designed by the Cytopathology Laboratory of the University of Chicago. Ploidy measurements of insulinomas, taken alone, did not discriminate well between benign and malignant states. However, the single malignant insulinoma could be clearly recognized, for it was one of only two lesions in that group with 5N-exceeding rate (5N-ER) values of 1% or greater. (5N-ER is defined as the percentage of aneuploid nuclei with nuclear DNA content greater than 5N.) On the other hand, seven of eight malignant gastrinomas had ploidy values of 2.5N or greater (our definition of an aneuploid state) and/or had 5N-ER values of 1% or greater, while five of six benign gastrinomas had ploidy values of less than 2.5N and had 5N-ER values of 0%. In addition, the two most aggressive tumors had the highest ploidy and 5N-ER values. Nuclear DNA cytometric studies appear to offer promise as an aid in the evaluation of pancreatic islet cell tumors, particularly gastrinomas.
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PMID:Nuclear DNA analysis of insulinomas and gastrinomas. 282 71

Synaptophysin, an Mr 38,000 integral membrane glycoprotein of neurotransmitter vesicles, has been identified in diverse primary neuroendocrine (NE) tumors of both neural and epithelial origin (Wiedenmann and co-workers, Proc Natl Acad Sci USA 1986; 83: 3500-3504). In the present study, metastases of several types of NE tumors, including medullary thyroid carcinoma, gastrinoma, insulinoma, small (oat) cell carcinoma of the lung, gastrointestinal carcinoid, and neuroblastoma, were examined for the presence of synaptophysin by immunocytochemistry, with the use of tissue sections as well as centrifuged cell suspensions and by immunoblotting of tumor proteins. The results show that expression of synaptophysin can be maintained during formation of metastases. Therefore, the authors propose that synaptophysin antibodies be used for the positive identification of metastatic NE tumors, notably in differential diagnosis. The possible implications of these findings for tumor diagnosis are discussed.
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PMID:Synaptophysin identified in metastases of neuroendocrine tumors by immunocytochemistry and immunoblotting. 311 96

Insulinoma, glucagonoma, gastrinoma (Zollinger-Ellison syndrome), vipoma, somatostatinoma and a tumor that secretes human pancreatic polypeptide are the primary endocrine-secreting tumors of the pancreas. hormones are produced by specific tumor cell types and cause a variety of dramatic clinical pictures. Diagnosis often requires hormone assays. Computerized tomography may be helpful. Definitive surgical treatment is possible, but metastases may be present.
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PMID:Primary endocrine-secreting pancreatic tumors. 610 68


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