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)

Somatostatin-receptor scintigraphy using the 111In-labelled somatostatin-analogue octreotide ([111In-DTPA-D-Phe1]-octreotide) was performed in 40 patients with carcinoid tumours. In 31/40 patients, this scintigraphy proved positive compared with the 33/40 patients whose tumours were disclosed on CT scans. In addition, 18 previously unidentified lesions were detected with this scintigraphy. Two of these lesions represented previously undetectable primary tumours. It is concluded that somatostatin receptor scintigraphy using [111In-DTPA-D-Phe1]-octreotide has a future role in the staging of patients with carcinoid disease.
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PMID:Somatostatin receptor scintigraphy of carcinoid tumours using the [111In-DTPA-D-Phe1]-octreotide. 830 27

The distribution and dosimetry of the somatostatin analog 111In-DTPA-octreotide was evaluated in 6 patients. Whole body scintigraphy in anterior and posterior projections was performed 0.5, 5, 24 and 48 hours after injection. Region-of-interest analysis for different organs and the whole body was used to determine 111In octreotide half-life-corrected uptake in absolute and relative terms. A rapid initial uptake was seen in the kidneys (2-7%), the spleen (2-6%) and in the liver (4-8%). A lower uptake was seen in the pituitary gland (maximum 0.3%), the thyroid (maximum 0.07%), in the female breast (maximum 1.2%), in the urinary bladder and in the intestinal tract. The elimination pattern varied between different organs. The effective dose equivalent was evaluated to be in the range 0.08 to 0.13 mSv/MBq (average 0.10 mSv/MBq). The behavior of 111In-DTPA-octreotide suggests follow-up scintigraphy in a period extending up to at least 24 hours after injection.
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PMID:Distribution and dosimetry of 111In DTPA-D-Phe-octreotide in man assessed by whole body scintigraphy. 830 73

Recently, [111In]-DTPA-D-phenylalanine-octreotide was introduced for clinical use. This radioligand binds specifically to somatostatin receptors and is suitable for SPECT examinations. The aim of this study was to clarify whether an increased somatostatin receptor density can be imaged and quantified in patients with endocrine ophthalmopathy (e.o.). 7 patients between 34 and 55 years with e.o. at stages III to VI and 4 controls between 38 and 63 years were examined. All patients and controls received approximately 200 MBq [111In]-DTPA-D-phenylalanine-octreotide by IV injection. A SPECT examination was performed 4 hours after injection and a normalised tracer uptake (A(n)) was calculated for both orbitae. In patients with e.o. the values of A(n) were significantly higher compared with controls (P = 0.002). There was a correlation between A(n) and exophthalmus stages according to Hertel with r = 0.844 (P = 0.001). These results indicate that [111In]-DTPA-D-phenylalanine-octreotide SPECT might be useful for the in vivo assessment of an increased somatostatin receptor density in e.o. These findings could have an impact on the treatment with somatostatin analogous in e.o.
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PMID:[[111In]-DTPA-D-phenylalanine octreotide SPECT for the scintigraphic imaging of enhanced somatostatin-receptor density in endocrine ophthalmopathy]. 830 85

Various tumors of neuroendocrine origin that have amine precursor and decarboxylation (APUD) characteristics can be visualized in vivo after intravenous injection of the somatostatin analogue [123I-Tyr3]-octreotide. However, the relatively short effective half-life of this compound and the high background of radioactivity in the abdomen are drawbacks in its application. Therefore, an 111In-coupled somatostatin analogue ([111In-DTPA-D-Phe1]-octreotide) was developed. This analogue is excreted mainly via the kidneys, 90% of the dose being present in the urine 24 h after injection. Using 111In-octreotide scintigraphy, 7 out of 7 gastrinomas, 4 out of 7 insulinomas, 1 out of 1 glucagonoma, 3 out of 3 unclassified apudomas, but none out of 18 exocrine pancreatic carcinomas were visualized. Also, 19 out of 19 carcinoids, 15 out of 15 glomus tumors, 8 out of 12 medullary thyroid carcinomas, 6 out of 6 small cell lung carcinomas, 4 out of 4 growth hormone-producing and 6 out of 9 clinically nonfunctioning pituitary adenomas were visualized. Apart from APUD-cell-derived tumors, 111In-octreotide scintigraphy was also successfully applied to visualize breast cancer, lymphomas and granulomas. In 39 out of 50 patients with breast carcinoma, 10 out of 11 patients with non-Hodgkin lymphomas, 3 out of 3 patients with Hodgkin's disease, and 8 out of 8 patients with sarcoidosis, tumor sites accumulated radioactivity during octreotide scintigraphy. In a considerable number of patients with carcinoids and glomus tumors, but also in patients with granulomas and lymphomas, 111In-octreotide scintigraphy revealed more tumor sites than did conventional imaging techniques.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:111In-octreotide scintigraphy in oncology. 835 73

The distribution and elimination characteristics of the 111In-labelled somatostatin analogue OctreoScan111 were studied in 23 patients with malignant tumours. The substance exhibited a rapid blood elimination following a bi-phasic pattern. The initial part of the elimination curves showed a t1/2a of between 0.27 and 3.6 h. The patients investigated had creatinine clearance rates ranging from 33 to 124 ml/min. However, within this range, no apparent correlation was found between the OctreoScan111 elimination rate and kidney function. Also no correlation was observed between the amount of administered activity and the elimination rate of OctreoScan111. The serum radioactivity of 6 patients was analyzed with respect to molecular size. These experiments showed that OctreoScan111 circulated unbound in serum. About 3% of the radioactivity, most probably representing 111In-chloride of DTPA-111In-chloride, circulated protein-bound. The elimination of OctreoScan111 radioactivity in urine displayed a bi-phasic pattern. Size separation of the radioactivity appearing in the urine after 24 h showed a higher molecular weight when compared with OctreoScan111, indicating the existence of a metabolite of the injected substance. The results obtained are discussed in the light of a potential role for the substance in systemic radiotherapy.
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PMID:Distribution and elimination of the somatostatin analogue (111In-DTPA-D-Phe1)-Octreotide (OctreoScan111). 839 31

In this review, we evaluate radiological techniques currently used to localize gastroenteropancreatic (GEP) endocrine tumors. We also describe the visualization, using intravenous administration of two isotope-labelled somatostatin analogs (123-I-Tyr3-octreotide and 111In-DTPA-octreotide), of islet cell tumors in 25 patients and carcinoids in 39 patients. The primary tumor as well as previously unrecognized distant metastases were visualized in 20 of the 25 patients (80%) and in 37 of the 39 (95%). Parallel in vitro detection of somatostatin receptors on those tumors also visualized in vivo showed that ligand binding to the tumor in vivo represents binding to specific somatostatin receptors. The detection of somatostatin receptors on tumors in vivo predicted a good suppressive effect of octreotide on hormonal hypersecretion by these tumors. It is an easy, quick and harmless procedure, valuable in the localization of primary endocrine pancreatic tumors and their often radiologically and clinically unrecognized metastases. Future prospective controlled studies comparing this procedure with other radiological investigative techniques should demonstrate its sensitivity and specificity and determine the place of somatostatin receptor imaging in the localization of GEP endocrine tumors.
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PMID:The visualization of gastroenteropancreatic endocrine tumors. 839 33

Receptors for the neuropeptide somatostatin (SS) were evaluated in vitro and in vivo in various human lymphatic tissues, ie, thymus, spleen, and lymph nodes; thymic carcinoids and thymomas were also tested. The receptors were measured in vitro using receptor autoradiography on tissue sections incubated with the SS analog 125I-[Tyr3]-octreotide or 125I-[Leu8,D-Trp22,Tyr25]-SS-28. All tissues were SS-receptor positive for either radioligand, except the thymomas. In thymic tissue, the receptors were diffusely located in the medulla, presumably on epithelial cells. In the spleen, the red pulp was strongly labeled. In the lymph nodes, the germinal centers were preferentially labeled. In all tissues, the receptors were of high affinity (kd thymus, 0.84 nmol/L; kd spleen, 1.6 nmol/L; kd lymph node, 0.62 nmol/L) and specific for SS. Displacement by nanomolar concentrations of SS-14, SS-28, and octreotide was observed, as was guanosine triphosphate dependency. The in vivo visualization of somatostatin receptors was performed after injection of 111In-DTPA-octreotide and gamma-camera scintigraphy. The spleen, but not thymus or lymph nodes, were visualized. These data suggest an important role for SS in regulating immune functions through SS receptors in thymus, spleen, and lymph nodes. Furthermore, SS may regulate neuroendocrine functions in the thymus.
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PMID:In vitro autoradiographic and in vivo scintigraphic localization of somatostatin receptors in human lymphatic tissue. 840 Feb 64

After injection of 111In-labelled DTPA-D-Phe1-octreotide, intraoperative tumour localisation was performed using a scintillation detector in 23 patients with neuroendocrine tumours. Count rates from suspect tumour lesions and adjacent normal tissue were expressed as a ratio before (Rin situ) and after (Rex vivo) excision. 111In activity concentration ratios of tumour tissue to blood (T/B) were determined in a gamma counter. In patients with midgut carcinoids, (all scintigraphy positive), false Rin situ recordings were found in 4/29 macroscopically identified tumours. T/B ratios were all high (27-650). In patients with medullary thyroid carcinomas (eight out of ten scintigraphy positive), misleading Rin situ results were found in 4/37 macroscopically identified tumours. T/B ratios were lower (3-39) than those seen in midgut carcinoids. Two out of four patients with endocrine pancreatic tumours had positive scintigraphy, reliable intraoperative measurements and very high T/B ratios (910-1500). One patient with a gastric carcinoid had correct measurements in situ and ex vivo with high T/B ratios (71-210). In situ measurements added little information to preoperative scintigraphy and surgical findings using the present detection system. Rex vivo measurements were more reliable. The very high T/B ratios seen in midgut carcinoids and some endocrine pancreatic tumours would be favourable for future radiation therapy via somatostatin receptors.
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PMID:Intraoperative detection of somatostatin-receptor-positive neuroendocrine tumours using indium-111-labelled DTPA-D-Phe1-octreotide. 861 78

Scintigraphy with radiolabelled analogue of somatostatin is highly sensitive in detecting carcinoid tumors especially if performed with Single Photon Computed Tomography (SPECT). In this report we describe our experience with 111In-DTPA-Octreotide in a female patient affected by a small asymptomatic intrabronchial carcinoid demonstrated by CT scan and bronchial endoscopy performed after recurrent left pneumonias. Planar views and SPECT images, using 111In-DTPA-Octreotide, were collected before and four hours after the first endoscopic laser resection. All groups of SPECT images were positive in the left parahilar region but at a different degree. Scans performed after resection showed a low degree of uptake which was considered to be probably secondary to local swelling; CT scan was negative. Follow up endoscopic biopsy repeated at six months, showed a relapse always in the same site; CT scan of the thorax was again negative. 111In-DTPA-Octreotide images obtained at twelve months were positive always in the left parahilar region, CT scan was negative but another biopsy was not possible. Therefore it was suspected a relapse of the carcinoid which was probably growing only through the bronchial wall without spreading towards the bronchial lumen and/or the lung parenchima. In this occasion, it was also thought that images collected four hours after resection could be positive not only for swelling but for a relapse as well. In every scintigraphic session, SPECT images presented higher quality than planar. This case suggests that 111In-DTPA-Octreotide SPECT is a non-invasive diagnostic technique which could be applied as a follow-up tool especially to patients with no-secreting carcinoid neoplasm and/or with negative or doubtful endoscopic and radiological investigations.
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PMID:A case of bronchial carcinoid: diagnosis and follow-up with 111In-DTPA-octreotide. 862 94

Predictive tests for treatment with somatostatin analogues have been asked for by clinicians. We have shown previously that somatostatin receptor (sstr) scintigraphy may be used to predict therapeutic outcomes for carcinoid patients receiving somatostatin analogues. However, almost 20% of patients with pathological tracer uptake fail to respond to such treatment. To increase further the reliability and prognostic value of sstr identification, we investigated the presence of mRNA for the subtypes sstr1 and sstr2 by in situ hybridization on tumor specimen from 25 carcinoid patients (22 midgut, 2 foregut, and 1 hindgut), all receiving somatostatin analogue treatment (12 lanreotide, 8 octreotide, and 5 octastatin) and compared this to the therapeutic response evaluated as inhibition of hormone secretion. Expression of sstr2 mRNA could be detected in 15 patients, all responding to somatostatin analogue treatment and showing pathological tracer uptake in tumor lesions at sstr scintigraphy. In the remaining 10 patients, no sstr2 mRNA could be detected, and none of the patients responded to somatostatin analogue treatment. Three of these 10 patients failed to accumulate tracer activity at sstr scintigraphy, whereas 7 had a pathological uptake of [(111)In-DTPA-D-Phe(1)]-octreotide. We conclude that in this group of carcinoid patients, there was complete agreement between the presence of mRNA for sstr2 detected by in situ hybridization and therapeutic outcome. In patients with pathological tracer accumulation without expression of somatostatin sstr2 mRNA, other sstr may be present that can bind the somatostatin analogue but not inhibit hormone secretion.
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PMID:A comparison between the efficacy of somatostatin receptor scintigraphy and that of in situ hybridization for somatostatin receptor subtype 2 messenger RNA to predict therapeutic outcome in carcinoid patients. 865 98


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