Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Polyclonal antibodies directed towards synaptophysin were raised against a synthesised peptide corresponding to amino acids 246 to 260 of the human synaptophysin sequence. The antibodies, when applied for immunocytochemical staining, showed a staining pattern identical to that of the commercially available monoclonal antibody SY-38. A radioimmunoassay for measurements of synaptophysin was developed using these antibodies and the peptide as standard and tracer. The radioimmunoassay was used for optimising the conditions for purification of synaptophysin from rat brain. No synaptophysin was detected in blood plasma in humans, not even during an embolisation treatment of tumour metastases in the liver, which induced tumour cell necrosis, in a patient with carcinoid tumours. By radioimmunoassay, synaptophysin was detected in cell homogenate from the PC-12 (160 ng/mg) and LCC-18 (40 ng/mg) cell lines and in the cell culture media. In the LCC-18 cell line the synaptophysin immunoreactivity was found in the plasma membrane, and the presence of synaptophysin was confirmed both by radioimmunoassay measurements and by the Northern blot technique. These data indicate that measurements of synaptophysin using this radioimmunoassay are reliable and that the assay can serve as a useful tool in further explorations of the biological effects of synaptophysin.
 ...
PMID:Development of polyclonal antibodies and evaluation of a sensitive radioimmunoassay for detection and measurement of synaptophysin. 752 90

Carcinoid tumors belong to the group of neuroendocrine tumors of epithelial origin, i.e., neuroendocrine carcinomas. These neoplasms usually occur in the gastrointestinal tract or bronchial system but are very rare neoplasms in the larynx. Since carcinoid tumors in this latter site may appear to be undifferentiated by light microscopy, they may possibly be misinterpreted and their neuroendocrine characteristics may remain unrecognized. Using immunohistochemical methods, three carcinoid tumors were studied and showed positive immunostaining for markers of epithelial origin (cytokeratins, epithelial membrane antigen, carcino-embryonic antigen) and, in particular, for markers of neuroendocrine differentiation (chromogranin, synaptophysin, neuron-specific enolase). All tumors expressed calcitonin-, serotonin- and adrenocorticotropic-hormone-like immunoreactivity. In contrast, three poorly differentiated squamous cell carcinomas showed positive immunostaining for epithelial markers but did not show any immunoreactivity with markers of endocrine characteristics. Fine structurally, carcinoid tumor cells contained neurosecretory-type granules scattered throughout the cytoplasm. The present study demonstrated that (1) carcinoid tumors of the larynx possess distinct immunohistochemical characteristics that allow a clear classification, (2) it is advisable to use a battery of primary antibodies rather than rely on specificity and sensitivity of a single marker to establish diagnosis and (3) the fine structural demonstration of neurosecretory-type granules serves as a reliable adjunct to diagnosis.
 ...
PMID:Immunohistochemical and fine structural characterization of primary carcinoid tumors of the larynx. 754 78

Four cases are described of a distinctive morphologic variant of thymic carcinoid that was characterized by abundant stromal mucin admixed with the neuroendocrine elements resulting in a histologic picture reminiscent of metastatic mucin-secreting carcinoma. The patients were three men and a woman, aged 22 to 43 years. The tumors presented with symptoms of chest discomfort, cough, and dyspnea and were described as large anterior mediastinal masses on chest radiographs and computerized scans. Histologically, all cases showed nests and strands of tumor cells embedded in an abundant lightly eosinophilic, mucinous stroma with small cellular clusters as well as scattered single tumor cells seen floating in the mucin. The mucinous matrix was negative for periodic acid Schiff's and mucicarmine stains; alcian blue stains at pH 2.5 showed strong positivity of the mucinous material; this reaction was abolished by treatment with hyaluronidase, indicating the presence of nonepithelial stromal mucosubstances. Immunohistochemical stains showed strong positivity of the tumor cells with CAM 5.2, chromogranin, synaptophysin, and neuron-specific enolase, and negative staining with carcinoembyronic antigen and epithelial membrane antigen. Electron microscopy done in one case showed abundant dense-core cytoplasmic neurosecretory granules; there was no evidence of glandular secretory activity by the tumor cells. The tumors in two patients behaved in a highly aggressive fashion, with invasion of the chest wall, recurrence, and metastases to the lungs, pleura, and axillary, retroperitoneal, and mesenteric lymph nodes. Thymic carcinoid should be considered in the differential diagnosis of mediastinal neoplasms displaying prominent mucinous features. Application of immunostains and electron microscopy will be of value for establishing the correct diagnosis in this setting.
 ...
PMID:Thymic carcinoid with prominent mucinous stroma. Report of a distinctive morphologic variant of thymic neuroendocrine neoplasm. 757 90

We evaluated three cases of pigmented pulmonary carcinoid tumors that were retrieved from the files of the Armed Forces Institute of Pathology, Washington, DC. Clinical follow-up showed no indication of tumor recurrence or metastases, nor was there evidence of malignant melanoma. All three cases exhibited histologic features of typical carcinoid tumor; there were focal oncocytic changes in two cases. Finely dispersed, brown pigment, believed to be melanin, was distributed in two different patterns: in sustentacular cells (case 1) or within the tumor cells (cases 2 and 3). Fontana-Masson stain was positive in areas of this pigment in all cases. The tumor cells showed immunoreactivity for chromogranin, synaptophysin, keratin (AE1/AE3 and CAM-5.2), and S100 protein in all cases. Focal staining for vimentin and corticotropin was seen within neoplastic cells in two cases. The pigmented sustentacular cells in case 1 showed focal immunoreactivity for S100 protein and HMB-45. Ultrastructural studies of paraffin-embedded tissues were performed in two cases. They showed well-developed melanosomes in the pigmented sustentacular cells in case 1. In both cases, cytoplasmic neurosecretory-type granules were identified in neoplastic cells. These findings demonstrate that pigmented pulmonary carcinoid tumor has an immunohistochemical profile similar to that of typical pulmonary carcinoid tumor. In some instances, pigmented pulmonary carcinoid tumors may show ultrastructural evidence of melanocytic and neuroendocrine differentiation. These immunohistologic and ultrastructural findings distinguish pigmented pulmonary carcinoid tumor from malignant melanoma and support the concept of "multidirectional cellular differentiation."
 ...
PMID:Pigmented pulmonary carcinoid tumor. An immunohistochemical and ultrastructural study. 768 14

We report a case of primary renal carcinoid, which is a very rare neoplasm: to our knowledge, only 19 cases have been previously reported. The tumor displayed histologic features typical of carcinoid tumors from other sites, including growth in nests and ribbons, uniform cells with finely granular, eosinophilic cytoplasm, and stippled chromatin. Electron microscopy confirmed the presence of membrane-bound dense-core granules. Immunohistochemical analysis revealed staining for chromogranin A, neuron-specific enolase, Leu-7, and synaptophysin, as well as pancreatic polypeptide. An interesting finding was the positive staining for prostatic acid phosphatase, while staining for prostate-specific antigen was negative. Although prostatic acid phosphatase is commonly seen in primary gastrointestinal hindgut carcinoids, in this case a primary hindgut carcinoid was ruled out by clinical examination and endoscopy. The patient developed metastases to the liver, but was well and without symptoms 15 months after diagnosis.
 ...
PMID:Primary renal carcinoid. Case report and literature review. 768 15

For the sake of discussion, the markedly diversified tumors of the endocrine/neuroendocrine system are classified as those originating in classic epithelial endocrine organs (eg, adrenal cortical adenomas), from the diffuse endocrine cells (eg, jejunal carcinoid tumors), or from clusters of these cells (eg, islet cell tumors); and those arising from neurosecretory neurons (eg, neuroblastoma) or paraganglia (eg, carotid body tumor). Although traditional transmission electron microscopy is useful for identifying neurosecretory or endosecretory granules as such, with few exceptions (eg, insulin-containing granules with a complex paracrystalline core) it is not possible to ascribe a granule type (size, shape, or ultrastructure) to a distinct nosologic entity or secretory product because of their overlapping fine structures in different cell types. Immunoelectron microscopy methods utilizing colloidal gold-labeled secondary antibodies can be used to localize virtually any antigen (peptide or neuroamine) to a specific neurosecretory or endosecretory granule or other cell structure. General endocrine/neuroendocrine cell markers such as neuron-specific enolase, the chromogranins, and synaptophysin are useful in identifying neuroendocrine differentiation in a neoplasm using routine immunohistochemical procedures. The current relevance of the APUD concept of Pearse as well as the biologic importance of endocrine/neuroendocrine secretory products such as bombesin and insulinlike growth factors also are discussed.
 ...
PMID:Tumors of the endocrine/neuroendocrine system: an overview. 791 Jul 11

The monoclonal antibody KP-1 that recognizes the lysosome-associated glycoprotein CD68 was used together with antibodies to other antigens (actin, glial fibrillary acidic protein, keratin, neurofilaments, chromogranin, synaptophysin, S-100 protein, HMB-45, lysozyme, and HLA-DR) in a labeled streptavidin biotin immunoperoxidase method to phenotypically characterize 27 granular cell tumors, five schwannomas, five neurofibromas, two ganglioneuromas, three ganglioneuroblastomas, five carcinoid tumors, five malignant melanomas, and five examples of histiocytosis X. The neoplastic cells in all 27 of the granular cell tumors and four of the five schwannomas strongly stained for CD68, whereas none of the neurofibromas, ganglioneuromas, ganglioneuroblastomas, or carcinoid tumors contained CD68-positive tumor cells. These findings further strengthen previous observations, suggesting a histogenetic relationship between granular cell tumors and Schwann cells. KP-1 reactivity also was demonstrated in cells of histiocytosis X and malignant melanoma, complementing other studies that extend the tumor types positive in immunoperoxidase stains using this antibody.
 ...
PMID:Immunohistochemical demonstration of the lysosome-associated glycoprotein CD68 (KP-1) in granular cell tumors and schwannomas. 854 22

Two cases of paraganglioma of the urinary bladder are reported. Their immunohistochemical profiles and the clinical features are compared with other cases in the literature. The three pan-endocrine markers (neuron-specific enolase, synaptophysin and chromogrannin) were positive in both cases. Positivity to other neuropeptides (including the present two cases and those in literature) includes adrenocorticotropic hormone (three out of five cases), calcitonin (two out of nine cases), gastrin (two out of six cases), glial fibrillary acidic protein (one out of five cases), glucagon (two out of six cases), serotonin (five out of nine cases), and somatostatin (four out of eight cases). A previously unmentioned association between paraganglioma of the urinary bladder and carcinoid in the gastrointestinal tract is noted in one of the present cases. This peculiar association highlights the importance of multiplicity of tumours of the neuroendocrine system other than the classical multiple endocrine neoplasia syndromes.
 ...
PMID:Paraganglioma of the urinary bladder: an immunohistochemical study and report of an unusual association with intestinal carcinoid. 810 19

Non-small cell lung cancer with neuroendocrine differentiation may represent a subset of patients with a more aggressive (like small cell lung cancer) or less aggressive (like carcinoid) biological behavior. To investigate their prognostic significance, immunohistochemical stains for 4 neuroendocrine markers (neuron-specific enolase, chromogranin A, Leu-7, and synaptophysin) and carcinoembryonic antigen (CEA) were studied in 260 patients with surgically resected stage I and II non-small cell lung cancer. The following percentages of cases were positive for each marker: neuron-specific enolase, 70.0%; chromogranin A, 14.2%; Leu-7, 7.7%; synaptophysin, 11.2%; and CEA, 68.5%. Sixty-one (23.5%) were positive for > or = 2 neuroendocrine markers. When compared to adenocarcinoma, squamous cell carcinoma displayed lower positivity for CEA and > or = 2 neuroendocrine markers. There was no significant difference in stage, site of relapse (distant versus local), disease-free, or overall survival for each marker individually or for those with > or = 2 neuroendocrine markers. Multivariate analysis showed that higher nodal stage (N1 versus N0), tumor stage (T2 versus T1), older age, and the presence of mucin predicted for poorer overall survival. Neuroendocrine markers and CEA were not of prognostic significance in this group of patients with resected stage I and II non-small cell lung cancer.
 ...
PMID:The prognostic significance of neuroendocrine markers and carcinoembryonic antigen in patients with resected stage I and II non-small cell lung cancer. 818 76

We report the morphological features of an unusual cardial gastric tumour in a 72 year-old white man. Histologic examination revealed two adjacent, "side by side", but not merged, components: a poorly differentiated one and a typical moderately-differentiated gastric adenocarcinoma. Both components were also found in the metastatic lymph nodes. Histochemical (Grimelius) and immunohistochemical (neuron specific enolase, chromogranin A, synaptophysin) studies revealed the endocrine nature of the poorly differentiated component, which however, was not argentaffin and did not show immunoreactivity for specific endocrine substances. The neoplastic lesion was classified in the carcinoma-carcinoid spectrum as collision-type tumour. Our data suggest the double and independent origin of the two components.
 ...
PMID:Adenocarcinoma and atypical carcinoid: morphological study of a gastric collision-type tumour in the carcinoma-carcinoid spectrum. 856 96


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>