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)

Molecular characterization of neuroendocrine (Merkel cell) carcinoma of the skin. Review of the literature and report of three cases. Although neuroendocrine carcinoma of the skin (NECS) is comparatively a rare clinical-histological entity, numerous morphological and ultrastructural studies have been carried out since the tumor was identificated by Toker (1972). Recently immunocytochemistry has allowed a better molecular characterization (immunophenotype) of this tumor and a more exact diagnosis. The main problem for the pathologist is the differential diagnosis between NECS and skin neoplasms--both primitive and metastatic--which require a more aggressive treatment. Often the classical morphological criteria do not distinguish NECS from non-Hodgkin's lymphoma, amelanotic melanomas, cutaneous metastases of lung small cell carcinoma or of neuroblastoma. The co-expression of cytokeratins and neurofilaments constantly found in NECS, is surely the best differential criterion from non-neuroendocrine carcinomas. Furthermore, the typical paranuclear location of both the intermediate filaments in NECS is a distinctive peculiarity as opposed to lung microcytoma, where cytokeratins and neurofilaments, when present, show widespread perinuclear positivity. Chromogranin A is found only in a small percentage of tumor cells, whilst synthesis of calcitonin, somatostatin, gastrin, ACTH, is very rare. Finally, the lack of common leukocyte antigen (CLA), S-100 protein and vimentin in NECS rules out the diagnoses of lymphoma, melanoma and sarcoma respectively.
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PMID:[Molecular characterization of cutaneous neuroendocrine (Merkel cell) carcinoma. Review of the literature and presentation of a caseload]. 209 Oct 10

Fifteen neuroendocrine carcinomas of the skin (Merkel cell tumors) were stained within the constraints of tissue availability by the Grimelius method and immunohistochemically for keratin, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), S-100, common leukocyte antigen (CLA), met-enkephalin, bombesin, calcitonin, ACTH, gastrin, and somatostatin. Focal argyrophilia was present in 5 of 12 tumors. All tumors tested demonstrated immunoreactivity for NSE and 5 tumors were positive for keratin. One tumors appeared to demonstrate focal ACTH-like immunoreactivity, but otherwise no immunoreactivity for the above mentioned polypeptide hormones was noted in 11 completely studied tumors. One tumor contained histologically obvious areas of squamous differentiation in addition to areas of Merkel cell tumor. In various tumors, keratin immunoreactivity was present either in areas of histologically obvious squamous differentiation, in randomly scattered single cells not histologically identifiable as squamous, or in a paranuclear dot-like distribution. Immunoreactivity for CEA, S-100 and CLA was not present in any tumors. The lack of met-enkephalin and the presence of squamous differentiation in these tumors indicates multidirectional differentiation in a fashion not phenotypically typical of Merkel cells.
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PMID:Neuroendocrine carcinoma of the skin: an immunohistochemical study of tumor markers and neuroendocrine products. 243 2

The development of a radiolabelled somatostatin analogue Indium-111-Pentetreotide makes the detection of somatostatin receptor-bearing tumours by scintigraphic techniques possible. The existence of high-affinity binding sites for somatostatin has been described previously for most endocrine active tumours of the gastroenteropancreatic system (GEP), malignant lymphomas, small cell lung carcinomas, a subgroup of breast tumours and several types of neuroendocrine related human tumours. Using this new diagnostic tool we investigated some head and neck tumours of neuroendocrine origin (carcinoid of larynx, Merkel cell carcinoma, paragangliomas) with the newly developed radiolabelled somatostatin analogue Indium-111-Pentetreotide whether in vivo visualisation of somatostatin receptors might be possible. In cases not accessible for surgery but with a positive receptor status we started a specific therapy with the somatostatin analogue octreotide. The preliminary results suggest that this new isotopic scanning technique in a diagnostic tool and a predictive method for an effective therapy of those head and neck tumours which revealed highly specifically a positive receptor status. The therapeutical results using the somatostatin analogue octreotide indicate that this new concept is an ideal therapeutic strategy for those neuroendocrine head and neck tumours which cannot be controlled by surgical procedures.
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PMID:[Detection of somatostatin receptors in tumors in the area of the head and neck and their clinical importance]. 790 99

Through the development of somatostatin scintigraphy with the labeled somatostatin analog Indium111-Octreotide, it has recently become possible to accurately diagnose primary tumors of the APUD system as well as their metastases, since these tumors usually have somatostatin receptors. Experience with this method is already available for endocrine and exocrine tumors of the gastrointestinal tract, neuroendocrine and breast tumors, small cell bronchial carcinomas and certain lymphomas. In the present study, this new diagnostic technique was used for the first time in various head and neck tumors (carcinoid of the larynx, Merkel cell tumor, glomus tumor of the carotid and glomus jugulare tumor). Concurrently, some of these tumors shown by this diagnostic method to be somatostatin receptor positive were treated using the somatostatin analog Octreotide, a therapeutic approach new for the ENT-specialty. Our initial results prove that the detection of the ENT tumors which we studied by means of receptor scintigraphy is reliable. The preliminary results of this Octreotide therapy show a growth inhibitory effect, especially for those tumors of the head and neck which are inoperable or are difficult to approach surgically.
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PMID:Somatostatin receptor scintigraphy and therapy of neuroendocrine (APUD) tumors of the head and neck. 872 46

Radiolabeled somatostatin analogs have shown uptake in a variety of tumors. These include carcinoid, Merkel cell carcinoma, pheochromocytoma, islet cell tumor, and other tumors with somatostatin receptors. Radiolabeled somatostatin analog imaging with Indium-111-DTPA-pentetreotide permits whole body imaging, providing a new safe and effective means for detection of primary tumors and metastatic foci in neoplasms with somatostatin receptors. This imaging modality is helpful in screening the entire body as well as evaluating questionable foci of disease identified by conventional imaging modalities. This case report demonstrates the utility of computed tomography (CT) and radiolabeled somatostatin imaging as complementary modalities in the workup of a patient with metastatic carcinoid tumor.
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PMID:Metastatic carcinoid tumor imaged with CT and a radiolabeled somatostatin analog: a case report. 906 82

Merkel cell carcinoma is a rare neuroendocrine tumor of the skin. Prognosis is very poor particularly when systemic disease is present. Surgery, chemo and/or radiotherapy treatment are not able to guarantee long survival and quality of life is also very poor. We know that neuroendocrine tumor can be in possession of receptors for somatostatin; during the past years, these receptors have been demonstrated in vivo by octreoscan. We report a case of a patient suffering from metastatic Merkel cell carcinoma; because he was elderly, neither chemotherapy nor radiotherapy were possible as a consequence of the explosion of the disease after surgery. The presence of receptors for somatostatin analogues (octreoscan) allowed treatment with octreotide causing the immediate disappearance of metastasis. After ten months of treatment the patient presents a complete remission of disease. Octreotide, the most important somatostatin analogue, represents a primary role in the neuroendocrine tumor management; the drug also lacks of toxicity.
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PMID:[Merkel cell tumor. Report of case and treatment with octreotide]. 948 35

Merkel cell carcinoma (MCC) is an unusual malignant primary skin tumor, having a high incidence of local recurrent, and regional and distant metastasis. Due to its capacity to express somatostatin receptors, it can be detected in vivo with 111In-pentetreotide scintigraphy (Ostreoscan). We present a case of a MCC whose scintigraphy revealed regional metastases of a primary frontal cutaneous tumor that had been removed previously. The results verified a good correlation with clinical, radiological an histopathological findings.
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PMID:[Merkel cell carcinoma. Utility of scintigraphy with 111In-DTPA-pentetreotide]. 1048 Nov 12

Regional positron emission tomography (PET) imaging with F-18 Fluorodeoxyglucose (FDG) was performed in a patient with pathologically proven Merkel cell tumor around the right knee region. Prior to the PET imaging, whole-body Indium-111 octreotide scan was performed in this patient but was negative. F-18 FDG was offered as an attempt to image this somatostatin-receptor negative Merkel cell tumor. The PET images delineate a series of focal abnormal uptake along the right lower extremity without evidence of distant metastasis. Patient was treated locally. The positive accumulation of F-18 FDG in Merkel cells may offer a tool for defining the extent of this rare neuroendocrine tumor.
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PMID:F-18 FDG Accumulation in an Octreotide Negative Merkel Cell Tumor. 1083 3

Merkel cell carcinoma (cutaneous neuroendocrine carcinoma) is a highly malignant, neuroendocrine skin tumor. It mostly occurs in elderly patients in the sun-exposed skin of the head and neck and the extremities. Merkel cell carcinomas develop as fast-growing dermal tumors. They are characterized by a high frequency of lymph-node metastases (50%) and local recurrences (25-77%). The 5-year survival rate is 30-74%. Histology reveals uniform, round cells with a small cytoplasmic rim expressing cytokeratin 20, neurofilament, synaptophysin, chromogranin, and neuron-specific enolase. Ultrastructurally, 100-200 nm electron dense granules are typical findings. Wide surgical excision, followed by radiotherapy, is the treatment of choice. Regional lymph-node metastases should be treated by radical lymph-node excision and radiotherapy. In advanced metastatic Merkel cell carcinoma, a remission can be achieved by different chemotherapy schedules or the somatostatin analogue octreotide. However, the prognosis remains poor. The current knowledge about this disease and guidelines for effective diagnosis and treatment are given.
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PMID:[Merkel cell carcinoma: a diagnostic and therapeutic challenge]. 1135 30

Merkel cell carcinoma is a rare neuroendocrine neoplasm of the skin. The tumor most frequently affects elderly patients, with a preference for the head and neck. Eight patients affected by Merkel cell carcinoma have been observed at the General Surgery Unit II of the "Istituti Ospitalieri" hospital in Cremona, each in different stages of the disease; 75% of the cases involved the extremities, and in nearly all of the cases the tumor was nodular in appearance, with an average diameter of 2.2 cm. In 2 cases, the tumor was associated with rheumatoid arthritis, suggesting a dependency on the part of the neoplasm on the immune disorder and on steroid treatment. The available data confirm that in stage I of the disease, surgical treatment should be associated with radiotherapy in order to control the development of local relapses or metastases over time. In this stage, we observed a survival of 34 months (range, 24-48). In stages II and III, survival time falls, with very short duration of responses and poor quality of life as a result of the administration of cytotoxic molecules. Bearing in mind that any local relapse tends to appear within 12 months of the removal of the primitive tumor, that lymph node metastases appear in almost half of the patients, and that metastases over time are manifested in over a third of patients, it is essential to adopt a treatment capable of balancing the demand for longer remissions with a better quality of life. In this situation, we observed that treatment with somatostatin analogues achieves interesting responses without side effects, which suggests a close biological relationship between the tumor and somatostatin and that making a careful assessment of the prognostic factors of the disease can guarantee a correct therapeutic choice.
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PMID:Clinical experience on eight cases of Merkel cell carcinoma. 1284 61


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