Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Imaging with I-131 MIBG has proved useful for the detection of pheochromocytoma, neuroblastoma, and other neoplasms of neural crest origin. The authors present a case of a patient who was initially diagnosed as having follicular carcinoma of the thyroid in which I-131 MIBG played a key role in leading to the diagnosis of medullary carcinoma of the thyroid. Local and distant metastases were detected using I-131 MIBG imaging. Uptake of I-131 MIBG by medullary carcinoma of the thyroid has both diagnostic and therapeutic implications.
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PMID:Detection of medullary carcinoma of the thyroid with I-131 MIBG. 787 4

Familial neuroendocrine tumors are reviewed. The most dramatic advances have been the application of molecular genetic techniques to define the etiologies and develop predictive testing for patients with multiple endocrine neoplasia type 1 and type 2 syndromes. All three neoplastic lesions involved in multiple endocrine neoplasia type 1 (parathyroid, pituitary, and pancreatic islet) have shown loss of heterozygosity at chromosome 11. By contrast, the most consistent occurrence of loss of heterozygosity in tumors from multiple endocrine neoplasia type 2 patients was not at chromosome 10 but at chromosome 1p. Molecular genetic testing of multiple endocrine neoplasia type 1 and type 2 family members at risk provides a powerful tool for early identification and treatment of susceptible individuals. Efforts to clarify familial neuroendocrine tumors without associated multiple endocrine neoplasia syndromes continue. The best characterized tumor of this type is familial medullary thyroid carcinoma. Familial paraganglioma, neuroblastoma, and carcinoid also are reviewed. Potential barriers to genetic screening for familial neuroendocrine tumors are discussed.
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PMID:Familial risk for neuroendocrine tumors. 809 15

The authors report the case of a female infant who was referred at the age of 18 months for a left latero-cervical mass. This child belongs to a family with a history of multiple endocrine neoplasia (MEN) type 2a (10 persons in 4 generations had medullary thyroid carcinoma and/or pheochromocytoma). Surgery was performed with complete excision of an encapsulated tumor and pathological examination reported a typical ganglioneuroblastoma. No amplification of N-myc oncogene was observed. The probability of the child carrying a MEN-2a gene is estimated 2 to 4%, by DNA analysis. The patient has received no further treatment and is still free of disease 4 years later. The diagnostic problems of this tumor after basic tests were between neuroblastoma and medullary thyroid carcinoma. The link between neuroblastoma and MEN-2a syndrome is discussed because both diseases belong to the group of neural crest tumors.
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PMID:Cervical neuroblastoma and multiple endocrine neoplasia type 2a. 809 52

The histological localization of the ret proto-oncogene (proto-ret) product was examined in neural crest-derived and neuronal tissues together with their neoplastic counterparts by immunohistochemistry using a polyclonal antibody. Schwann cells, neurons, sympathetic ganglia, and cells of the adrenal medulla were positive for the proto-ret product, whereas melanocytes were negative. Positive results were obtained from neural crest-derived tumours such as schwannoma (69 per cent, 11/16), neurofibroma (59 per cent, 13/22), neuroblastoma (80 per cent, 4/5), phaeochromocytoma (100 per cent, 3/3) and medullary thyroid carcinoma (100 per cent, 3/3). The antibody reacted with all of the 22 astrocytomas examined. With negative proto-ret expression in melanocytic tumours, proto-ret expression was considered to correlate with the differentiation of some lineages of neural crest-derived cells.
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PMID:Expression of the ret proto-oncogene product in human normal and neoplastic tissues of neural crest origin. 819 28

Metaiodobenzylguanidine (MIBG) is a specific marker for neuroendocrine tumours, such as phaeochromocytoma, neuroblastoma, medullary thyroid cancer (MTC) and paraganglioma, but it suffers in some cases (especially in MTC) from a lack of sensitivity. Thallium is a well-known marker of cellularity with a great sensitivity and a lack of specificity. In order to determine whether the association of these two markers is able to improve the detection of neuroendocrine lesions, 137 scintigraphic examinations using MIBG and thallium were performed in 101 patients referred for suspicion or follow-up of neuroendocrine tumours. Thallium chloride was first injected (1 MBq/kg), images being acquired about 20 min after injection; 123I-MIBG (4 MBq/kg) was then injected and images acquired 5 and 24 h later. In patients with phaeochromocytoma or neuroblastoma, thallium scintigraphy appeared of little help since no tumoural site was discovered by thallium accumulation alone. In contrast, thallium examination seemed of interest in the detection of paraganglioma and MTC, the association of the two radiopharmaceuticals increasing the number of detected sites.
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PMID:Utility of thallium-201 and iodine-123 metaiodobenzylguanidine in the scintigraphic detection of neuroendocrine neoplasia. 828 75

The processing of two homologous precursors, pro-neuropeptide Y (pro-NPY) and pro-pancreatic poly-peptide (pro-PP), was studied in four neuroendocrine cell lines after transfection: CA-77 medullary thyroid carcinoma cells, AtT-20 corticotrope pituitary cells, RIN2A-19 pancreatic endocrine cells, and NB1 neuroblastoma cells. Northern blot analysis indicated that the AtT-20 cells only expressed precursor convertase 3; in contrast, NB1 cells only expressed precursor convertase 2, whereas the RIN2A-19 and CA-77 cells expressed both enzymes. Despite these differences in expression pattern of precursor convertases the four cell lines were, surprisingly, indistinguishable in respect to their processing of pro-PP and pro-NPY. In all four cell lines, pro-NPY was almost completely converted to NPY, and, in all four cell lines, only around 50% of the PP precursor was converted to PP. The relatively poor processing efficiency of pro-PP was rather similar to the processing efficiency of the endogenously produced precursors in the respective cell lines, pro-calcitonin (CA-77), proopiomelanocortin (AtT-20), proinsulin (RIN2A-19), and pro-vasoactive intestinal polypeptide (NB1). At least in the CA-77 cells, NPY and PP were apparently sorted to the regulated secretory pathway, as upon stimulation with secretagogue the release of the transfected peptides increased in parallel with the endogenously expressed peptide, calcitonin gene-related peptide. Mutagenesis studies showed that on the N-terminal side of the di-basic processing site, the otherwise important difference in structure between PP and NPY, a proline for glutamine in position 34, was not responsible for the difference in processing efficiency. On the C-terminal side of the processing site, the efficient processing of pro-NPY could not be transferred to pro-PP by exchanging the whole C-terminal domains of the precursors. It is concluded that pro-NPY is processed more efficiently than pro-PP in all neuroendocrine cell lines tested independent on their expression of the two main precursor convertases and that mutagenesis data indicate that the structural element responsible for the efficient processing of pro-NPY is not located on the N-terminal side of the dibasic processing site.
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PMID:Processing of two homologous precursors, pro-neuropeptide Y and pro-pancreatic polypeptide, in transfected cell lines expressing different precursor convertases. 851 71

The authors describe the possible application of Tc-99m (V) DMSA scintigraphy in pancreatic neuroendocrine tumors. In consideration of the common embryonic origin of these tumors and other neoplastic diseases (medullary thyroid carcinoma, pheocromocytoma, neuroblastoma) that have been well studied with radionuclide imaging, five cases of pancreatic neuroendocrine tumors (two insulinomas, one vipoma, and two unclassified neuroendocrine tumors) were successfully visualized with Tc-99m (V) DMSA scintigraphy, thus giving an overall "imaging confirmation" of the histologic and/or cytologic results in terms of primary and metastatic localization. The authors point out the importance of their results, obtained in a simple and repeatable manner, and suggest a real comparison in this setting between this approach and octreotide scintigraphy.
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PMID:Preliminary evaluation of the usefulness of Tc-99m (V) DMSA in pancreatic neuroendocrine tumors. 869 81

Since February 1990, 74 patients (116 studies) underwent scintigraphy with meta-[131I]iodobenzylguanidine ([131I]MIBG). Eighteen patients had pheochromocytomas, 2 paragangliomas, 2 malignant insulinomas, 1 carcinoid, 2 medullary thyroid carcinoma and 49 children had neuroblastomas. Scintigraphy was performed following a thyroid blockade, at 24 and 48 hours after i.v. injection of 0.5 mCi/1.7 m2 [131I]MIBG. Grade of heart intensity (GHI) uptake and the intensity of salivary gland visualization (SGI) were estimated semiquantitatively, according to the method of Nakajo et al. Sensitivity in the primary pheochromocytomas was 93.9%; sensitivity and specificity in the primary neuroblastomas were 93.7% and 100% respectively; in the secondary neuroblastomas they were 100%, and 100%. Metastases in 2 malignant insulinomas and in 1 case of medullary thyroid carcinoma were also demonstrated. Only one false negative (in pheochromocytoma) and one false positive (Conn's syndrome) result was obtained. Mean values and range of MIBG uptake measured according to Shulkin's procedure were: for pheochromocytoma 3.95% (0.1-15), primary neuroblastoma 0.7% (0.05-1.92%), and neuroblastoma metastases 0.12% (0.002-0.83%). Assessment of [131I]MIBG uptake seems to be helpful in the follow-up of some neural crest tumors and is essential as a prelude to [131I]MIBG therapy.
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PMID:Meta-[131I]iodobenzylguanidine in the scintigraphic evaluation of neural crest tumors. 900 42

The international workshop on metaiodobenzylguanidine (MIBG) and radiolabeled somatostatin analogs held in Rome in June, 1994 addressed a wide range of topics which might be classified into five broad general themes: Theme 1. The role of MIBG for the location of neuroendocrine tumors. A) The range of tumors in which MIBG scintigraphy is effective (pheochromocytomas, neuroblastoma, chemodectoma and other APUDomas). B) The increasing popularity of 123I as a radiolabel for MIBG (potential advantages in planar and SPECT imaging). C) MIBG as the prototype of a family of radiopharmaceuticals exploiting the biogenic amine uptake and storage mechanisms. (Other radiohalides 124I, 125I, 87Br, 211At, 18F; other PET radiopharmaceuticals such as 11C-epinephrine, 11C-hydroxyephedrine). Theme 2. The role of MIBG as an in vivo scintigraphic probe of the sympathetic nervous system. A) Cardiac sympathetic innervation (in cardiomyopathy, myocardial infarction, and as a prognostic index for cardiac transplantation). B) Pulmonary MIBG uptake as index of pulmonary endothelial/sympathetic function (MIBG by both the intravenous and inhaled routes of administration). Theme 3. MIBG for the radiopharmaceutical therapy of neuroendocrine tumors. A) Treatment of neuroblastoma early in the natural history of the disease (MIBG therapy as initial management, MIBG therapy combined with other modalities--e.g., chemotherapy and bone marrow transplantation). Theme 4. The role of radiolabeled somatostatin analogs for the location of neuroendocrine and other tumors. A) The range of tumors in which somatostatin receptor radiopharmaceutical scintigraphy is effective (pituitary tumors, central nervous system tumors, carcinoids, islet cell tumors, medullary thyroid carcinoma, small cell lung cancer, APUDomas). B) The superiority of 111In over 123I as a radiolabel (the future of potential 99mTc and other labels). C) Somatostatin receptor scintigraphy in autoimmune and other disorders. D) Pentetreotide as the prototype of a wide range of radiolabeled peptides as radiopharmaceuticals for the in vivo depiction of the receptors for peptide hormones, lymphokines, paracrine and other information transmitting molecules (the general concepts include the use of long-acting, slowly degraded analogs and the development of generally applicable labeling techniques. Examples include 123I-ANF, labeled interleukins and other lymphokines). Theme 5. Comparisons of MIBG and pentetreotide scintigraphy for the location of neuroendocrine tumors. A) The range of neuroendocrine and other tumors (e.g., pheochromocytomas, neuroblastomas, carcinoids, islet cell tumors and other APUDomas).
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PMID:Ten years of experience with MIBG applications and the potential of new radiolabeled peptides: a personal overview and concluding remarks. 900 76

Familial neuroendocrine tumors are reviewed. The most dramatic advances have been in the application of molecular genetic techniques to define the affected genes and to develop predictive testing for patients with multiple endocrine neoplasia syndromes. Germline mutations at specific loci of the RET proto-oncogene have been demonstrated in patients with multiple endocrine neoplasia types IIA, IIB, and familial medullary thyroid carcinoma not associated with multiple endocrine neoplasia. This has led to direct DNA testing for these mutations in patients at risk for these syndromes. The approach to predictive testing, diagnosis, and early treatment of these patients is discussed as a model for the approach to hereditary cancers. Linkage testing with DNA markers is still required for patients with multiple endocrine neoplasia type I because the responsible gene has not yet been isolated. Efforts to clarify the etiologies of other familial neuroendocrine tumors not associated with multiple endocrine neoplasia continue. Familial pheochromocytoma, neuroblastoma, and carcinoid also are reviewed. The use of molecular genetic techniques as a powerful tool for the early identification and treatment of susceptible individuals is emphasized.
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PMID:Familial neuroendocrine tumors as a model of hereditary cancer. 909 Apr 93


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