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)

High numbers of high-affinity somatostatin binding sites have been found on carcinoid tumors, gastrinomas, small cell lung cancers and the majority of medullary thyroid cancers, enabling in vivo visualization of these tumors with octreotide scintigraphy. A comparison of the results obtained at our institution and another 15 centers in Europe show a few remarkable similarities and differences. The overall sensitivity of octreotide receptor scintigraphy to detect the primary GEP tumor and its metastases is high, e.g. 80-90%. The main difference was found in gastrinomas and to a lesser extent in insulinomas. These differences might be attributed to different scanning protocols. Furthermore, octreotide scintigraphy also has a high sensitivity to localize the primary tumor and its metastases causing Cushing's syndrome by ectopic production of ACTH or CRH. Octreotide scintigraphy is a new, sensitive and noninvasive technique to localize somatostatin receptor expressing endocrine tumors and their metastases.
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PMID:Somatostatin receptor scintigraphy in carcinoids, gastrinomas and Cushing's syndrome. 769 38

Neuroendocrine tumors of the gastroenteropancreatic system represent a group of tumors with various diagnostic problems. Especially detection of primary tumor lesions is often difficult. Endoscopic ultrasonography is a relatively new imaging procedure localizing insulinomas preoperatively in about 90% of cases. Thus, previously used invasive preoperative imaging methods are usually unnecessary. The combination of endoscopic ultrasonography and somatostatin receptor scintigraphy allows visualization of gastrinomas in 90% of cases. Somatostatin receptor scintigraphy can also visualize metastatic lesions of gastrinomas and carcinoids in the whole body with high accuracy. In surgical management of a gastrinoma, duodenal transillumination and intraoperative ultrasound should be performed in all cases to exclude small duodenal or periduodenal, extrapancreatic tumors. US, CT, and MRI should be mainly used to exclude local and distant metastases. Angiography is helpful in detecting anatomical variations of abdominal vessels preoperatively. Due to the excellent results of endoscopic ultrasonography and somatostatin receptor scintigraphy in localizing insulinomas and gastrinomas, transhepatic portal venous sampling appears to be obsolete.
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PMID:[Imaging methods in diagnosis of neuroendocrine tumors of the gastrointestinal tract]. 775 24

In a prospective study of 13 patients (three males and 10 females; mean age 53 [8-82] years) the value of somatostatin receptor scintigraphy (SRS) and endoscopic ultrasonography (EUS) was compared with transabdominal ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of insulinoma (six patients) or gastrinoma (seven patients). There were ten separate primary lesions of each tumour type, proven histologically. For insulinoma the sensitivity of EUS was 90%, SRS 10% and CT, US and MRI together 20%. For gastrinoma the sensitivity of EUS was 90%, SRS 100%, and 30% for the other three methods together. Thus EUS had a high diagnostic localizing sensitivity for both tumours, while SRS was highly sensitive only in the diagnosis of gastrinoma, not insulinoma. The value of CT, MRI and conventional ultrasonography lies in their ability to visualize distant metastases.
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PMID:[Somatostatin receptor scintigraphy and endoscopic ultrasound for the diagnosis of insulinoma and gastrinoma]. 783 41

Rats were administered the somatostatin analogue octreotide 15 micrograms intraperitoneally twice daily for 4 weeks after intraportal injection of somatostatin receptor-positive pancreatic tumour cells (CA-20948) and somatostatin receptor-negative colonic tumour cells (CC531). Octreotide significantly inhibited the growth and development of somatostatin receptor-positive tumour cells in the liver. The median number of liver tumours was 286 (range 146 to greater than 500) in the treated animals and more than 500 (range 250 to in excess of 500) in the controls (P < 0.05). This significant difference in tumour load was also represented in the mean(s.e.m.) liver weight (14.5(3.7) g in animals given octreotide versus 17.9(3.0) g in the controls). No effect of octreotide treatment was found on the growth and development of somatostatin receptor-negative tumour cells in the liver. The median (range) number of tumours was 6.5 (0-425) in the treated animals and 11.0 (0-475) in the controls. Mean(s.e.m.) liver weights were 14.0(5.7) g and 11.8(4.5) g respectively. There was no difference in serum levels of growth hormone, prolactin and insulin-like growth factor between control and octreotide-treated rats. The growth inhibition of somatostatin receptor-positive tumour cells was unlikely to be the result of suppressed secretion of one of these tumour growth factors. Octreotide may be useful for the treatment of patients with somatostatin receptor-positive hepatic metastases, which can be demonstrated by somatostatin receptor scintigraphy.
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PMID:Somatostatin receptor-dependent growth inhibition of liver metastases by octreotide. 795 4

The localization of islet cell tumours presents a challenge to the radiologist and requires meticulous attention to detail in both technique and interpretation. As several imaging techniques are capable of demonstrating the tumour and none is absolutely accurate, a rational approach to the localization of these tumours requires a careful consideration of cost, sensitivity and the availability of special expertise. In almost all cases, initial imaging is performed with a combination of transabdominal ultrasound and CT. This will demonstrate the tumour and any hepatic metastases in about 40% of gastrinomas, 80% of insulinomas and almost all other functioning and non-functioning tumours. Where these tests are negative or equivocal, arteriography (which may be combined with ASVS) is the next line of investigation. If the tumour remains undetected, it is likely to be a small insulinoma or gastrinoma. Further investigation is dependent on local practice and the tumour type. Endoscopic ultrasound is rapidly emerging as a technique of high sensitivity in detecting small pancreatic tumours and may also demonstrate extrapancreatic gastrinomas. Transhepatic venous sampling and somatostatin receptor imaging have the advantage that they are not directly dependent on tumour size and they are particularly applicable to difficult cases where other imaging modalities are negative. TPVS is invasive and, while sensitive for insulinomas, is frequently unhelpful in gastrinomas. Somatostatin receptor scintigraphy, on the other hand, is more sensitive for gastrinomas. In future, MRI may prove to be at least as accurate as CT but as yet its exact role is uncertain. At the time of surgery, intraoperative ultrasound is a useful adjunct to palpation, and may avoid a standard distal pancreatectomy in patients with insulinoma.
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PMID:Imaging islet cell tumours. 801 89

Diagnosis of endocrine pancreatic tumor syndromes is based on the characteristic spectrum of symptoms and the demonstration of inappropriately high serum levels of the tumor's secretory products. Available imaging methods cannot visualize pancreatic tumors with a diameter of less than 1 cm and are diagnostic in 50 to 60% only. With the introduction of endoscopic sonography and somatostatin receptor scintigraphy, detection of tumors has been improved. Therapeutic principles include surgical extirpation, primarily in the absence of metastases, and medical control of symptoms. In the case of metastatic disease, tumor growth and symptoms can be controlled by a variety of procedures including somatostatin analogs with and without additional alpha-interferon, polychemotherapy, embolization, surgical tumor debulking and liver transplantation.
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PMID:[Diagnosis and therapy of active endocrine pancreatic tumors]. 805 73

A new derivative of octreotide SDZ 219-387 [PnAO-(D)Phe(1)-octreotide] was synthesized, which binds specifically and with high affinity to somatostatin receptors in vitro (pKi = 9.79 +/- 0.16). This new somatostatin analogue chelates technetium-99m under mild labelling conditions in good yields. The resulting [99mTc]SDZ 219-387 was stable up to 6 h after labelling and could be isolated in a pure radiochemical and chemical form by high-performance liquid chromatographic purification. The intravenous administration of purified [99mTc]SDZ 219-387 revealed that the radioligand was rapidly cleared from circulation, and tumour uptake of 0.38% ID/g was observed at 1.5 h post injection. [99mTc]SDZ 219-387 specifically interacted with somatostatin binding sites on the tumour. However, the radioligand is highly lipophilic and excreted mainly through the hepatobiliary system. As a consequence, [99mTc]SDZ 219-387 exhibits increased background activity and therefore is not appropriate for the in vivo visualization of somatostatin receptor-positive tumours and/or their metastases in the abdomen.
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PMID:Synthesis, radiochemistry and biological evaluation of a new somatostatin analogue (SDZ 219-387) labelled with technetium-99m. 806 50

Five patients with hepatic metastases of midgut carcinoid underwent somatostatin receptor scintigraphy with indium-111 pentetreotide before and during treatment with octreotide. Octreotide treatment changed the biodistribution of 111In-pentetreotide significantly. Whereas the radioactivity in liver, spleen and kidney decreased, hepatic metastases showed increased contrast. In one patient, liver metastases could only be detected during octreotide treatment. These data suggest that the diagnostic reliability of somatostatin receptor scintigraphy in carcinoid liver metastases is not necessarily compromised by octreotide therapy. Because of different biodistributions, the detection of liver metastases may even be improved during octreotide therapy.
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PMID:Improved visualization of carcinoid liver metastases by indium-111 pentetreotide scintigraphy following treatment with cold somatostatin analogue. 810 Jan 92

In a prospective study, ten patients with recurrent medullary thyroid carcinoma (markedly elevated calcitonin levels) were investigated by means of somatostatin receptor scintigraphy (SRS) with 111Inpentetreotide. Scintigraphically, 30 sites of pathological uptake were found, mostly located in the neck and upper mediastinum. So far, 18 suspected tumour sites underwent histological examination and 14 of them could be verified as metastases of medullary thyroid carcinoma (MTC). The remaining four putative tumour lesions turned out to be false positive scintigraphic findings caused by chronic inflammation and somatostatin receptor positive tumours other than MTC. We conclude that SRS is a promising imaging modality for localization of MTC recurrence and may thus make a contribution to better management of this patient group.
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PMID:The potential value of somatostatin receptor scintigraphy in medullary thyroid carcinoma. 810 Jun 24

In a prospective study, 18 patients with recurrent medullary thyroid carcinoma (MTC) underwent magnetic resonance imaging (MRI) of the neck and mediastinum and somatostatin receptor scintigraphy (SRS) with 111In-labeled pentetreotide. In nine patients with macroscopic MTC, 17 corresponding lesions were found on MRI and SRS; in addition, 13 suspicious lesions were seen on SRS only. Histological confirmation was available for 19 metastatic lesions, showing MRI to be true positive in 13 metastases, SRS in 18. In minimal residual disease (n = 10), MRI and SRS were compared with the histological findings in three patients and with selective venous catheterization (SVC) in seven patients. Corresponding findings on MRI and SVC were seen in one of seven, whereas SRS and SVC showed concordant localization of tumor recurrence in five of seven. Histological examination demonstrated MTC tissue in one of three cases; MRI and SRS were false positive in one of three cases, while in the others the interpretation remained uncertain. In conclusion, SRS is a promising imaging modality for localization of MTC recurrence. MRI provides better spatial resolution and thus facilitates the planning of surgery for macroscopic metastases. In minimal residual disease, SRS turned out to be superior in detecting occult MTC recurrence, confirming SVC findings.
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PMID:Somatostatin receptor scintigraphy and magnetic resonance imaging in recurrent medullary thyroid carcinoma: a comparative study. 833 Aug 72


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