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)

Neuroendocrine enteropancreatic tumors (NEEPTs) include tumors developing from the pancreatic islets and the duodenal loop, and those developing from gut serotonin-secreting cells (mid-gut carcinoids). When functioning, they are rare tumors with frequently inconsistant clinical and biological characteristics. Provocative dynamic tests are very useful. Their natural history, with the exception of insulinomas and mid-gut carcinoids, is still incompletely known due to their rarity, relatively recent description, slow evolution and the absence of definitive reliable markers for prognosis. The following factors affect the natural history of NEEPTs. (1) Inclusion or not within the spectrum of multiple endocrine neoplasia type-1 (MEN1), such an integration often dramatically modifies the management strategy. In patients with MEN1, NEEPTs are often multiple, diffusely spread in the duodenopancreatic area and of small size. Definite cure by surgery is then very scarce. Mid-gut carcinoid tumors are the most protean NEEPTs. In contrast to appendiceal carcinoids, usually with a benign course, mid-gut carcinoids have a more malignant course and are very common indeed: local transmural invasion, early metastasis to lymph nodes and/or liver, and symptoms from hormone oversecretion. Carcinoid syndrome is usually well controlled by long-acting somatostatin analogs. (2) Disease spreading, i.e. liver and bone metastases, are the major causes of death in patients with NEEPTs. Liver metastases (LMs) are synchronous in about 75% of the patients with LMs but may develop during follow-up (about 25% of the patients with LMs were without LMs at the initial evaluation). Development of bone metastases has a very poor prognosis accompanying LM progression.
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PMID:Natural history of neuroendocrine enteropancreatic tumors. 1094 Jun 88

Malignant paraganglioma is a rare and slow growing tumour of neuroendocrine origin. At the time of diagnosis, the tumour is usually widespread, with limited therapeutic options. A variety of functional imaging studies are available for staging the disease, guiding therapy and monitoring treatment response. These include 123I-MIBG or 131I-MIBG, 111In-pentetreotide or 111In-lanreotide (somatostatin analogues), and 18F-FDG positron emission tomography. Various radionuclides, including 131I and 90Y, can be targeted to the tumour using MIBG or pentetreotide. Such targeted radionuclide therapy may provide valuable long-term palliation in such patients. We present two cases with metastatic paragangliomas who had widespread soft tissue and bone metastases. One patient was treatment naive and the second had received previous chemotherapy. The functional imaging work-up performed and the targeted radionuclide therapies considered in these patients are described. Both patients were treated with 131I-MIBG. Partial tumour response and complete symptomatic and hormonal response was achieved in one patient; in the second patient there was no change.
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PMID:Functional imaging as an aid to decision-making in metastatic paraganglioma. 1133 5

The local microenvironment at the sites of cancer metastases protects tumour cells from anticancer drug-induced apoptosis via mechanisms, such as soluble growth factors and cytokines. The concept of antisurvival factor (ASF) therapy as a component of anticancer treatments aims at neutralising the protective effect conferred upon cancer cells by the survival factor(s) derived by the local microenvironment, in order to enhance the sensitivity and/or reverse the resistance of tumour cells to other anticancer therapeutic strategies. Herein, we review the translation of this concept from ex vivo studies to clinical applications in the setting of prostate cancer refractory to androgen ablation (stage D3). At this stage, which predominantly involves bone metastases, insulin-like growth factor 1 (IGF-1) production (either growth hormone (GH)-dependent or GH-independent) can protect tumour cells from apoptosis, despite the significant suppression of androgens. The application of the ASF therapeutic concept involves the combination of dexamethasone (which suppresses GH-independent IGF-1) and somatostatin analogue (which suppresses endocrine, GH-dependent IGF-1) with the pro-apoptotic effect of the testicular androgen suppression by sustained use of LHRH analogues. In stage D3, patients who had failed anti-androgen withdrawal, chemotherapy and also had several other adverse prognostic features, the ASF-based combination achieved durable objective responses and major symptomatic improvement, paving the way for future applications of this approach. The ASF-based combination therapy illustrates a novel paradigm in cancer treatment: anti-tumour treatment strategies may not only aim at directly inducing cancer cell apoptosis, but can also target the tumour microenvironment and neutralise the protection it confers on metastatic cancer cells. The favourable toxicity profile of this therapeutic approach calls for its testing in a randomised controlled setting in metastatic prostate cancer and, conceivably, in other IGF-1-responsive malignancies.
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PMID:Combination of dexamethasone and a somatostatin analogue in the treatment of advanced prostate cancer. 1182 17

Motilin-secreting neuroendocrine tumours have been rarely described. Immunohistochemical, biochemical and motility investigations were performed in a 62-year-old man with liver and bone metastases of a motilin-secreting neuroendocrine tumour originating from a rectal polyp removed 14 years previously. Symptoms related to liver metastases were reduced by a right hepatectomy whereas plasma motilin levels were decreased. The patient also underwent two operations for spinal cord decompression and survived 6 more years under medical treatment, mainly octreotide. Immunohistochemistry revealed predominant expression of motilin-containing cells, with rare cells expressing somatostatin and pancreatic polypeptide, and staining for only one panendocrine marker, neurone-specific enolase. A liver tumour extract contained 17.9 microg motilin per gram of tissue, which permitted to isolate and characterize human motilin, which was identical to porcine motilin. Plasma column gel chromatography revealed a main peak corresponding apparently to porcine motilin. The patient had no symptoms of disturbed motility. Gastric emptying and gastroduodenojejunal motility were found within normal limits. The absence of alterations of gut motility was perhaps related to sustained autonomous motilin production. The long evolution of this type of tumour suggests that plasma motilin determination should be added to the investigations for neuroendocrine tumours.
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PMID:An unusual metastatic motilin-secreting neuroendocrine tumour with a 20-year survival. Pathological, biochemical and motility features. 1184 83

Patients with clinically evident medullary thyroid cancer should have a total extracapsular thyroidectomy with bilateral central neck dissection and an ipsilateral prophylactic or therapeutic modified (functional) radical neck dissection when the primary tumor is greater than 1 cm and when the central neck nodes are positive. A prophylactic contralateral neck dissection should be done when the primary tumor is bilateral and when there is extensive lymphadenopathy on the side of the primary tumor. Patients who have gross, unresectable residual medullary thyroid cancer should receive postoperative external radiotherapy. Patients who are carriers of germ-line RET proto-oncogene point mutations or have an elevated (basal or stimulated) calcitonin levels on screening should have a prophylactic total thyroidectomy before age 6 years. In patients with an elevated basal or stimulated plasma calcitonin level and an intrathyroidal nodule on ultrasound, a total thyroidectomy and central neck lymph node dissection should be done. Patients with persistent or recurrent medullary thyroid cancer should have a complete thyroidectomy (if not done initially) and bilateral central and modified radical neck dissection, including upper mediastinal lymphadenectomy. Patients who are symptomatic from distant medullary thyroid cancer metastases (diarrhea, flushing, weight loss, or bone pain) should be treated with somatostatin analogs. Bone metastases should be resected if possible, and symptomatic lesions that are unresectable should be treated with external radiotherapy. Cytoreductive procedures such as radiofrequency ablation or cryoablation for liver metastases should be considered in symptomatic patients to reduce tumor burden. Localized pulmonary metastases should be resected. Chemotherapy or radioactive immunotherapy (iodine 131 labeled carcinoembryonic antigen monoclonal antibody) protocols should be considered in patients with nonoperative widely metastatic progressing medullary thyroid cancer.
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PMID:Medullary thyroid cancer. 1205 61

Cytoreductive therapy is effective in the management of metastatic neuroendocrine tumors to the liver, independent of their functioning status. In functioning tumors, clinical endocrinopathies are relieved in most patients and this response usually lasts for several months. Major morbidity and mortality are not greater than the average complication rate for resection for nonneuroendocrine metastatic tumors at major centers; therefore, surgical outcomes appear to justify operative intervention. Patients whose primary tumor can be controlled, whose metastases outside the liver are limited, and who have a reasonable performance status are candidates for resection. The authors' data support the previous statements. The current mortality rate of 1.2% and major morbidity rate of 15% clearly represent the success of the operative approach in such complex cases (54% of patients received a resection of at least one lobe) [9]. A symptomatic response in the 95% range with a median response of 45 months adds many months of symptom-free survival to the lives of most patients [9]. In the literature reviewed for this article, more than half of the patients also underwent a major hepatic resection and 40% of them had concurrent resection of the primary tumor. These data confirm that resection in selected patients is not more complicated or risky than resection for other metastatic tumors. Endocrinopathies have not increased anesthetic or operative risk in this population; however, these results are the product of managing these patients over time, becoming familiar with their clinical syndromes, and being active in the prevention of life-threatening endocrine complications (i.e., carcinoid crisis). The authors have learned over time that patients with valvular disease are not good candidates for surgery. These patients develop right-sided heart failure with an increase in the central venous pressure. This condition can result in massive hemorrhage during the liver resection because of the difficulty in controlling backbleeding from the hepatic veins [26]. Correction of valvular disease is warranted for safe liver resection. The authors' current policy is to rule out valvular disease in every patient with carcinoid tumors and repair the valves prior to hepatic resection when indicated [27]. This policy clearly has decreased the complication rate. Even though liver transplantation seems to be very attractive as a means of eradicating the disease, this has not been common in clinical practice because of the shortage of allografts, and the overall costs and complications of the procedure override its benefits, especially when compared with partial hepatectomy. Current methods to detect the spread of disease that were not readily available in the past, such as MRI and indium-111 pentetreotide (Octreoscan), may expand the applications of transplantation and allow for better selection of candidates. The option of transplantation is still open for improvement and is dependent on organ availability and better staging of the disease. Metastases from neuroendocrine tumors are hypervascular, favoring the application of MRI as the single imaging method; MRI not only evaluates the location and characteristics of the lesions but also determines the relationship with major vessels and bile ducts. Spiral CT scan has been used extensively in the past with acceptable results. Indium-111 pentetreotide functions on the base of somatostatin receptors present in these tumors, but its use has not been established definitely in the work-up of these patients. Perhaps the best use of indium-111 pentetreotide is in the evaluation of disease beyond the primary and liver locations, including bone metastases; its use therefore will likely affect the preoperative work-up of candidates for transplantation [28]. Once the patient has been deemed to have resectable disease by the preoperative work-up, several steps need to be completed prior to surgery to decrease the effect of specific endocrinopathies. For patients with symptoms related to carcinoid tumors, preoperative preparation with 150 to 500 micrograms of somatostatin decreases the chances of carcinoid crisis, which is manifested by hemodynamic instability [29]. The use of this medication intraoperatively should be kept in mind because a carcinoid crisis can occur despite anesthetic premedication. For islet cell tumors, treatment of underlying endocrinopathy has been initiated before referral for surgical treatment in most patients. Surgery is appropriate for patients with metastatic neuroendocrine tumors for the following two reasons: (1) many of them still have the primary tumor in place and resection should be undertaken to avoid acute complications and (2) the addition of adjunctive ablative therapies to surgical resection accomplishes the control of greater than or equal to 90% of the bulk of the tumor. If preoperative evaluation indicates that less than 90% of the tumor is treatable, surgical therapy is contraindicated. Last, even when complete resections are performed, the recurrence rate for these tumors is extremely high. In practical terms, patients with metastatic neuroendocrine tumors are seldom cured. The best hope physicians can offer these patients is an extended survival period with minimal endocrine symptoms and decreased requirements of somatostatin analogs.
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PMID:Hepatic surgery for metastases from neuroendocrine tumors. 1273 41

Treatment of differentiated thyroid cancer is a success of modern medicine with the use of radioiodine ((131)I). However, a significant proportion of thyroid cancers may be non-iodine avid. Thyroid tumours are known to express somatostatin receptors. Octreotide, an analogue of somatostatin, can be combined with a radioactive isotope, such as (111)In-DTPA(0) to visualise tumours with high concentrations of somatostatin receptors. We assessed 18 patients with histologically proven metastatic or locally recurrent non-iodine avid thyroid carcinoma to determine the usefulness of (111)In-DTPA(0) octreotide scintigraphy compared to conventional radiology in diagnosing sites of metastasis. The diagnosis of metastatic disease was made using conventional radiology and all had prospective scintigraphy using (111)In-DTPA(0)octreotide. Of the 18 patients, 14 had octreotide-positive scans. In eight, the octreotide scans identified the same sites of metastases as conventional radiology, that is, were concordant. In nine patients, conventional radiology showed more extensive disease than revealed on the octreotide scans. In one patient with widespread bone metastases, octreotide gave a more detailed assessment of metastatic disease than conventional radiology. These data indicate that (111)In-DTPA(0)octreotide imaging for patients with non-iodine avid carcinoma of the thyroid may be a useful diagnostic and staging tool. One patient with Hurthle cell carcinoma metastatic to bone and a positive octreotide scan has been treated with (90)yttrium-labelled octreotide.
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PMID:Indium-111-labelled octreotide scintigraphy in the diagnosis and management of non-iodine avid metastatic carcinoma of the thyroid. 1286 13

To investigate somatostatin receptors (SSTRs) in primary or metastatic high-grade osteosarcoma, 18 patients (12 without metastases, 4 with synchronous lung, and 2 with metachronous bone metastases) underwent SSTR scintigraphy. After intravenous (i.v.) injection of 200-250 MPq of 111In-pentreotide, images were recorded at 4 and 24 hours. All patients underwent 99mTc-methylene diphosphonate (MDP) bone scan (BS). Scans were interpreted both with qualitative evaluation and with semiquantitative image processing, by means of tumor-to-background ratio modification over time. Primary tumor: SSTR scintigraphy was positive in 12 (75%) patients: 10 (83%) of the 12 nonmetastatic patients, and 2 (50%) of those with synchronous metastases. Metastases: SSTR scintigraphy was positive only in one (17%) of the six patients with metastatic disease. No relation was found between SSTR scintigraphy results and gender, histologic subtype, site, and size of the tumor. After primary chemotherapy, 15 patients underwent surgery of primary tumor; a good histologic response was found in 7 (64%) of the 11 patients with positive SSTR scintigraphy versus 1 (25%) of the 4 patients with negative SSTR scintigraphy. High-grade osteosarcoma exhibits somatostatin receptors, usually detectable in the primary tumor, but not in the metastatic lesions. The different expression of somatostatin receptors observed in primary and metastatic lesions, and in patients with tumors having different chemosensitivity, could indicate a possible relation between somatostatin receptors and biological behavior of the tumor.
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PMID:Somatostatin receptor (SSTR) scintigraphy in patients with osteosarcoma. 1462 33

A 68 year old Ecuadorian man was investigated for polyuria, polydipsia and weight loss of 3 kg during the previous two months. Insulin dependent diabetes mellitus was diagnosed 10 year before admission and treated with appropriate diet and insulin (35 U/d). 18 months before was diagnosed in El Ecuador of "multiple liver nodes non-suggestive of malignancy". Physical examination showed a large multinodular petrous hepatomegaly. There was no evidence of skin lesions. Results of laboratory studies included a basal plasma glucose level that ranged between 275-367 mg/dl (N=60-100), glycosylated haemoglobin of 8.9% (N<5) and a serum albumin of 2.8 gr./dl (N=3.4-4.8). At admission non-other laboratory alterations were detected. Computed tomography showed a mass on the head of the pancreas with loco-regional lymph nodes and liver metastases. Tumor markers were normal. Fine-needle aspiration cytology of the liver masses revealed the presence of liver metastases of a non-differentiated malignant tumor. A 111In-DTPAOC scintigraphy revealed the presence of somatostatin receptors in the liver metastases, also detecting the presence of multiple bone metastases in the axial and appendicular skeleton. Plasma glucagon level was 678 pg/ml (N<250). A diagnosis of metastatic glucagonoma was established and therapy with streptozocin, 5-FU, insulin and synthetic somatostatin analogs was initiated. Three months after the therapy initiation the patient was symptom free. Some weeks after the patient suffered from left hip pain, and a control 111In-DTPA scintigraphy showed progression of his bone metastases. In conclusion, glucagonoma must be suspected in all diabetic patients with metastatic liver, even in absence of necrotic migratory erythema. In these circumstances, plasmatic glucagon level and somatostatin receptors scintigraphy will be a useful tool for establishing the final diagnosis.
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PMID:[Diabetes mellitus and pancreatic tumor]. 1471 49

Carcinoid tumors were first described more than a century ago, but the treatment of patients with advanced disease remains a challenge to physicians. The etiology of carcinoid tumors, the biologic determinants of the growth of these malignancies, as well as the high frequency of multiple carcinoid and/or non-carcinoid tumors in patients with this disease also remain to be elucidated. A 5-decade analysis of 13,715 carcinoid tumors in the USA showed that distant metastases were demonstrated at the time of diagnosis in 12.9% of patients with this neoplasia. The overall 5-year survival rate for all patients with carcinoids regardless of the site, was reported to be 67.2%. The prognosis of patients with early stage disease is good and surgical resection is the standard form of treatment. The resection of local or regional metastases can result in cure for some cases. However, patients with metastatic dissemination have poor outcomes since chemotherapy is generally ineffective. Surgical resection of isolated hepatic metastases, surgical hepatic artery ligation or embolization produce responses in selected patients. Radiation therapy may ease the pain of bone metastases. The administration of long acting analogs of somatostatin can control the symptoms of diarrhea and flushing in patients with the malignant carcinoid syndrome. However, a complete regression of metastatic carcinoid tumors following the administration of somatostatin analog octreotide has been reported so far in only 3 cases. Other modalities of treatment, including liver transplantation and the administration of radiolabeled somatostatin analogs have likewise been applied in patients with advanced disease. It is expected that advances in proteomics research will contribute to our understanding of the mechanisms of diseases and aid in designing new drugs.
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PMID:A clinical overview of carcinoid tumors: perspectives for improvement in treatment using peptide analogs (review). 1564 13


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