Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Positron emission tomography (PET) makes it possible to study effects of medical treatment in vivo. Carcinoid tumors with liver metastases, especially those of midgut origin, produce serotonin via the precursors tryptophan and 5-hydroxytryptophan (5-HTP) and this overproduction contributes to the clinical symptoms of the carcinoid syndrome. Seven patients with histopathologically verified neuroendocrine tumors and liver metastases, five of whom with ileal carcinoids, one a lung carcinoid and one an endocrine pancreatic tumor, were included in the study. All patients had elevation of urinary 5-HIAA with the exception of one patient with a solitary liver metastasis of midgut origin. After an intravenous injection of 11C-5-HTP, PET was performed and the uptake of radioactivity in tumor tissue, normal liver and plasma were compared. All patients with elevated urinary 5-HIAA and also the patient with a solitary liver metastasis and normal urinary 5-HIAA had high accumulation and signs of a high rate of binding of 5-HTP in the liver metastases. The uptake was relatively homogeneous in midgut carcinoid liver metastases but in large necrotic metastases the radioactivity was localized to the periphery. In three patients PET examination was repeated after 3 months of interferon treatment and in agreement with circulating tumor markers and ultrasonography the uptake of 5-HTP was unchanged. Another patient who received the somatostatin analog somatuline progressed on treatment and accordingly the uptake of 5-HTP also increased. The experience with PET in neuroendocrine gastrointestinal tumors is very limited. Our results so far indicate that 5-HTP can be used to visualize serotonin-producing neuroendocrine tumors and furthermore it might prove to be of value to monitor the effects of treatment, possibly also as an early predictive test of the outcome of treatment.
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PMID:Positron emission tomography (PET) in neuroendocrine gastrointestinal tumors. 768 63

Somatostatin receptors have been described on the membrane of neoplastic cells derived from the APUD system and their expression has also been demonstrated on small cell lung cancer (SCLC) in vitro and in vivo. 21 patients with SCLC were studied using 111In-octreotide (111In-OCT) scintigraphy. Scintigraphic examinations were performed following intravenous (i.v.) injection of 111 MBq 111In-OCT with whole-body scintigraphy and planar scintigraphy of the thorax as well as the SPET technique. No short-term side effects were described following 111In-OCT administration. We studied the 111In-OCT biodistribution in 3 patients with serial scintigraphies at 1, 5 and 24 h. We used the 5 h as standard scanning time for the following 18 patients. The scintigraphic results were compared with those of other conventional diagnostic procedures. 111In-OCT detected 86% (48/56) of the lesions already known at the time of scintigraphy. It was positive in all 20 SCLC patients and negative in one lung adenocarcinoma. 111In-OCT showed high sensitivity for mediastinal metastases (94%) and good sensitivity for bone metastases (75%) and abdominal lymph node metastases (71%). 111In-OCT did not detect two liver metastases. 111In-OCT detected five unknown lesions which were confirmed by other diagnostic examinations. 111In-OCT was also effective in cancer patients with low levels of NSE. Our study shows that 111In-OCT scintigraphy is a reliable, non-invasive technique to detect primary SLCL and its locoregional or distant metastases. The clinical utility of receptor status characterisation obtained with 111In-OCT scintigraphy should be evaluated by means of an appropriate prospective study.
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PMID:Somatostatin receptor imaging of small cell lung cancer (SCLC) by means of 111In-DTPA octreotide scintigraphy. 771 23

Neuroendocrine liver metastases are rare, yet they represent an entity that has attracted much attention lately. The protracted course of neuroendocrine tumors and the hormone origin of their typical incapacitating symptoms constitute a logical basis for well founded and bespoke treatment. Demonstration of the liver secondaries is best done by ultrasonography (US) and contrast-enhanced computed tomography (CT), which on the whole have replaced the invasive angiography techniques. By use of histochemical and molecular biologic methods the exact nature of the tumor can be typified in tissue samples obtained percutaneously, laparoscopically, or surgically. Localization of nonpalpable metastases of the liver is best done by intraoperative US. Surgical removal of liver metastases is curative in some cases and is usually effective in relieving the symptoms. Also, palliative debulking or cytoreductive surgery is often worthwhile as it offers a chance of prolonged survival and symptom relief. Similar benefits are achieved by ischemic therapy preferably by temporary dearterialization, which in our department is done on an outpatient basis using a specially designed (externally controlled) occluder applied during a single laparotomy that includes debulking when appropriate as well as cholecystectomy. Hormonal therapy with somatostatin analogs may be used as a single treatment or in combination with ischemic therapy. It has an ensured symptom-reducing effect, whereas its influence on tumor growth is unsettled. Lately similar effects have been ascribed to human leukocyte interferon. In conclusion the specific characteristics of neuroendocrine tumors and the available treatment arsenal favor an active treatment approach in patients who have developed liver metastases.
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PMID:Neuroendocrine metastases of the liver. 774 Aug 14

We evaluated octreotide scintigraphy in 81 untreated patients who were suspected of having bronchial carcinoma. Octreotide scintigraphy visualized the primary tumour in all of 40 patients with non-small-cell lung carcinoma (non-SCLC), and all of 26 patients with SCLC. In the remaining patients, other bronchial disease and metastases from extrapulmonary carcinomas were also visualized. Mediastinal lymph node involvement and distant metastases were recognized in 5 of 15 and 1 of 7 patients with non-SCLC, respectively. In vitro, none of the non-SCLCs were shown to bear somatostatin receptors. We postulate that the visualization of non-SCLC during octreotide scintigraphy is caused by binding of labelled octreotide to activated leucocytes or to proliferating neuroendocrine cells around the tumours. In patients with SCLC, radiologically suspected lymph node involvement was visualized for 21 of 25 sites. Distant metastases, especially to the liver and abdomen, were missed for 14 of 20 sites, most probably because no laxatives were administered and single photon emission tomography of the abdomen was not performed. The failure to recognize liver metastases is most probably due to a comparable uptake of radioactivity by the surrounding normal liver tissue. In 15 of 26 patients, previously unrecognized tumour sites were suggested during octreotide scintigraphy, leading to a downstaging of 5 of 14 patients with limited disease. Unexpected cerebral metastases were suggested in five patients with either limited or extensive disease. In all four of these for whom follow-up was available, cerebral metastases became manifest 5-8 months after octreotide scintigraphy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The value of octreotide scintigraphy in patients with lung cancer. 782 21

In-111 pentetreotide scintigraphy of 10 patients with residual or metastatic medullary thyroid carcinoma is described. Six patients had sporadic tumor and 4 had MEN IIB. Foci of increased tracer uptake were observed in 9 patients: in the thyroid bed (4 patients), the mediastinum (3 patients.), the shoulder area and left lower abdomen (1 patient), and the left upper abdomen (1 patient). The 10th patient had no abnormal uptake. CT confirmed 2 mediastinal lesions and 2 out of 3 thyroid masses, but did not detect the thyroid remnants or the lesions in the shoulder area and abdomen. Lung lesions < or = 1 cm in diameter and ill-defined liver foci (2 patients) were seen on CT, but not on scintigraphy. Small liver metastases not demonstrated on CT or on scintigraphy were identified at surgery in a MEN IIB patient. Elevated urinary epinephrine was found in 2 out of 4 MEN IIB patients. In one, tracer uptake in the left adrenal corresponded to a mass on CT, to pathological uptake of MIBG and DMSA, and to a tumor removed at surgery. The second patient had peritoneal spread of malignant pheochromocytoma (at surgery), but negative CT and only a single focus in the left lower abdomen on scintigraphy. Somatostatin-receptor imaging is useful for the detection of residual and recurrent medullary thyroid carcinoma, and may identify pheochromocytoma in MEN IIB patients.
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PMID:Somatostatin-receptor imaging of medullary thyroid carcinoma. 791 71

It was the aim of the present study to examine whether 111In-pentetreotide, a somatostatin analogue with predominantly renal excretion, is a suitable receptor agonist for scintigraphic imaging of endocrine gastro-entero-pancreatic (GEP) tumors, and to evaluate the contribution of the usual imaging times 4 and 24 h p.i. In 36 patients, planar scintigrams obtained 4 h, and 24 h after i.v. injection of 111 or 222 MBq 111In-pentetreotide were compared to the results of other imaging procedures and of surgery. Single photon emission computed tomography (SPECT) was also performed 24 h p.i. Positive scintigraphies were obtained in 32 out of 36 patients (18/19 patients with carcinoid syndrome, 8/9 with non hormone-producing endocrine GEP tumors, 2/4 with gastrinomas, 1/1 with glucagonoma, 1/1 with a VIPoma, 2/2 with paragangliomas). In 9 patients tumor manifestations previously not detected by conventional imaging procedures were disclosed by 111In-pentetreotide scintigraphy. 24-h images yielded significantly more true positive findings than 4-h images. In 4 patients liver metastases missed on planar scans were detected by SPECT. A discrepancy between patient-based and organ-based analysis of the results was encountered thus indicating a possible intraindividual heterogeneity in somatostatin receptor expression. In conclusion, 111In-pentetreotide is a suitable somatostatin analogue for scintigraphic in vivo demonstration of somatostatin receptors and for imaging of most tumor manifestations in patients with endocrine GEP tumors. Further studies will have to evaluate whether or not a positive receptor scintigraphy predicts response to treatment with long-acting somatostatin analogues.
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PMID:111In-pentetreotide (somatostatin analogue) scintigraphy as an imaging procedure for endocrine gastro-entero-pancreatic tumors. 797 60

The difficult and controversial diagnostic and therapeutic management of patients having gastrinoma or insulinoma with multiple endocrine neoplasia type I (MEN-I) has been discussed by reference to the literature and a personal series of 45 gastrinoma/MEN-I patients followed consecutively at Bichat Hospital. In both gastrinoma/ and insulinoma/MEN-I patients, anatomic distribution and morphology of tumoral process(es) are usually multiple, diffuse, of small size, and associated with endocrine cell hyperplasia and even nesidioblastosis. These features enhance the difficulty of tumor localization and eradication. Despite the dramatic development of modern medical imagery and surgical experience, the real possibility, on a long-term basis, of curing the patients from their disease remains limited, especially in the gastrinoma/MEN-I patients. In the latter group, according to our experience, persistence or recurrence of the disease after surgery is usual, and metachronous hepatic metastasis development is frequently observed when the follow-up is long enough. Patients with liver metastases, however, seem to undergo a more indolent course than sporadic gastrinoma cases. In insulinoma/MEN-I patients, removal of the functionally dominant islet cell area(s) is essential. Various preoperative and intraoperative localization techniques allow efficacious selective pancreatic surgery in many cases. The latter refinements and the promises of long-acting somatostatin analogs, if confirmed, might restrict to exceptional circumstances the indication of near-total or total pancreatectomy.
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PMID:Current approach to the management of gastrinoma and insulinoma in adults with multiple endocrine neoplasia type I. 810 51

Most gastroenteropancreatic tumours express somatostatin receptors, allowing imaging using radiolabelled somatostatin analogues. Octreotide can be modified by coupling a DTPA moiety to the N-terminal D-phenylalanine to allow labelling with In111. We studied the comparative effectiveness of this radiopharmaceutical in identifying tumour extent. Twenty-two patients with metastatic gastroenteropancreatic tumours were scanned using [111In-DTPA-D-Phe1]-octreotide. In 11 patients with the carcinoid syndrome, one of six primary lesions was identified by CT scanning and by [111In-DTPA-D-Phe1]-octreotide scanning. Hepatic metastases were present in all patients, 9 of whom had positive scintigraphy. Two other sites of intra-abdominal uptake and four distant sites, not previously identified, were demonstrated. Five other distant sites were confirmed to be carcinoid metastases. All 11 patients with other gastroenteropancreatic tumours had positive scans, demonstrating 7/9 primary lesions, 12 intra-abdominal lesions, including hepatic metastases in all cases, and one distant lesion, all previously identified. Thus [111In-DTPA-D-Phe1]-octreotide imaging effectively identified the extent of metastatic disease from gastroenteropancreatic tumours, and confirmed lesions whose significance was uncertain following previous imaging procedures.
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PMID:Localization of metastatic gastroenteropancreatic tumours by somatostatin receptor scintigraphy with [111In-DTPA-D-Phe1]-octreotide. 815 92

Computed tomography during arterial portography (CTAP) and delayed high-dose iodine computed tomography (CT) have improved the preoperative localization of hepatic metastases from colon cancer. Nearly all patients presenting with malignant carcinoid syndrome have liver metastases, and removal of tumour bulk is considered the most effective means of management. To determine suitability for hepatic resection, CTAP and delayed high-dose iodine CT were used to evaluate the distribution of hepatic disease in two patients with malignant carcinoid syndrome. In both patients CTAP showed lesions not seen during recent dynamic incremented CT; the location of the lesions precluded resection. CTAP also demonstrated metastases less than 1 cm in diameter in one patient. Facial flushing (both patients) and hypotension (one) occurred during infusion of the contrast agent into the superior mesenteric artery. Because CTAP can demonstrate small hepatic metastases (less than 1 cm in diameter), it is recommended for patients with malignant carcinoid syndrome who are being considered for hepatic resection. The infusion of contrast media through the superior mesenteric artery may induce a carcinoid crisis, and prophylaxis with a somatostatin analogue is suggested.
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PMID:Computed tomography during arterial portography in malignant carcinoid syndrome: a report of two patients. 846 29

Scintigraphy with iodine-123 or indium-111 labelled somatostatin analogue (octreotide) was performed in 52 patients diagnosed as, suspected of, or at risk of having carcinoid tumours. In 32 of 37 (86%) patients in whom histologically proven carcinoids were still present, known tumour sites were visualized. Using 123I-coupled octreotide, 24 of 40 (60%) known extrahepatic sites were visualized, whereas all of 12 (100%) extrahepatic lesions were visualized after injection of 111In-coupled octreotide. Known liver metastases were not distinctly visualized with octreotide scintigraphy in 12 of 24 patients. In all but two of these cases, an even distribution of radioactivity in the liver was observed. This is most probably due to the fact that these liver metastases accumulated about as much radioactivity as does normal liver tissue. Previously unsuspected localizations or sites not recognized with other imaging techniques were found in 20 of the 37 patients. In 3 of 11 patients who were thought to have been surgically cured, and in 4 of 4 patients who were suspected of having carcinoids, octreotide scintigraphy showed abnormal accumulation of radioactivity. Histological or radiological evidence that additional sites noticed on octreotide scintigrams indeed represented tumour tissue was obtained in ten patients. Visualization of the carcinoids did not depend on the site of the tumour or on the presence or absence of hormonal hypersecretion, as measured by urinary 5-hydroxyindoleacetic acid and serum alpha-subunit concentrations. Apart from its use for tumour localization, octreotide scintigraphy, in consequence of its ability to demonstrate somatostatin receptor positive tumours, could be used to select those patients with the carcinoid syndrome who are likely to respond favourably to octreotide treatment.
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PMID:Somatostatin analogue scintigraphy in carcinoid tumours. 849 Dec 20


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