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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This review considers the pathologic features of epithelial tumors and tumor-like lesions of the duodenum and highlights potential pitfalls in their histological diagnosis. The tumor-like lesions include Brunner's gland hamartoma, myoepithelial hamartoma, and the mucosal polyps of the Peutz-Jeghers and juvenile polyposis syndromes. The true neoplasms are of two broad groups. The first includes duodenal adenomas and carcinomas, whose microscopic features, histogenetic relationships, and clinical significance closely mimic their commoner counterparts in the large intestine and which, when multiple, are closely associated with familial adenomatous polyposis coli. The second includes a number of uncommon endocrine cell tumors showing a great diversity of histological pattern, and which may be single or multiple. Among these are typical argyrophil carcinoids, which may secrete gastrin to give rise to the Zollinger-Ellison syndrome, and which may occur as part of the inherited multiple endocrine neoplasia syndrome type 1 (MEN-1); glandular somatostatin-rich, apparently nonargyrophil, carcinoids containing psammoma bodies that can be easily confused histologically with adenocarcinomas, and which are linked to type 1 neurofibromatosis (von Recklinghausen's disease) and phaeochromocytoma; and the gangliocytic paraganglioma, a rare tumor composed of neural elements, ganglion cells, and endocrine cells. Accurate histologic diagnosis of mucosal tumors and tumor-like lesions of the duodenum is important not only for immediate patient management, but also because it may provide the first clue to the existence of an inherited tumor syndrome, with its broader implications for the patient's family and potentially important consequences for genetic counseling.
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PMID:Epithelial and neuroendocrine tumors of the duodenum. 192 22

The neurofibromatosis type 1 (NF1) gene has been localized to the pericentromeric region of the long arm of chromosome 17. A chronology of events leading to the cloning of the NF1 gene is offered as a summary of modern gene hunting techniques. The gene was identified by its location rather than its function using positional cloning. Linkage analysis, based on DNA polymorphisms, is already available for prenatal and presymptomatic testing. This technique works only in cases when affected family members are available and is useless in spontaneous cases. The complete NF1 gene is huge, has a large number of exons, and is approximately 240,000 base pairs long. Its large size is consistent with the very high spontaneous mutation rate. The NF1 gene is evolutionarily conserved and expressed ubiquitously, not just in neural crest derivatives. Functional and structural homology with GAP (GTP [guanosine triphosphate]ase-activating protein) has been described. The GAP controls (or is controlled by) the ras oncogene. Aberration of ras function, which plays a fundamental role in growth, development, and differentiation, may play a role in the NF1 phenotype. Direct DNA diagnosis of mutations in the NF1 gene in clinical practice is premature. Current data suggest that the NF1 gene product may act as a tumor suppressor.
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PMID:The hunt for the neurofibromatosis gene. 195 78

This report presents a very rare case of a malignant "Triton" tumor developing in the thyroid. Although malignant "Triton" tumors have often been known to develop in cases of neurofibromatosis, Von Recklinghausen's disease, this patient showed no clinical evidence of that disease. Total thyroidectomy including left standard radical neck dissection was followed by postoperative irradiation to the neck. Despite this, local and distant metastases developed four months after treatment and the recurrent foci did not respond to chemotherapy or irradiation. The clinical course of this case mimicked that of anaplastic carcinoma of the thyroid and interestingly, a minimal lesion of papillary adenocarcinoma was found to exist concurrently in the thyroid gland of this patient.
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PMID:Malignant "triton" tumor in the thyroid--a case report. 196 Sep 8

The case of a 36-year-old patient with an intramedullary neurinoma of the thoracic spine without Recklinghausen's disease is presented. The intramedullary neurinoma is a very rare condition. Only 33 cases have been reported in the literature. To our knowledge, the case presented here is the first in German literature. The treatment of choice is tumor removal. The case described here was diagnosed by magnetic resonance imaging (MRI). Histologically, the tumor showed all features characteristic of a neurinoma. Postoperatively, the patient is nearly without complaints.
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PMID:[Intramedullary neurinoma. Case report]. 209 55

Tumors of the nerve sheaths are very unusual. They occur with the highest frequency in the head and neck region, yet only 4% have been found to occur within the paranasal sinuses. Only 40 cases of nerve sheath tumors with direct involvement of the paranasal sinuses have been reported in the world's literature to date. Three new cases of neurofibroma not associated with Recklinghausen's disease and one case of a schwannoma of the frontoethmoid and maxillary sinuses are presented. The clinical, radiographic, and histopathologic features of these lesions will be discussed with emphasis on electron microscopy and immunohistochemical differentiation of these rare and often confusing lesions.
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PMID:Nerve sheath tumors of the paranasal sinuses: electron microscopy and histopathologic diagnosis. 210 14

We report an unusual example of ovarian neurofibroma in a woman with neurofibromatosis (von Recklinghausen's disease). The neoplasm caused ovarian enlargement which surgically simulated malignant neoplasm. Ovarian neurofibromas are extremely rare and may arise from small myelinated nerves in the ovarian hilum.
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PMID:Neurofibroma of the ovary. 211 3

Von Recklinghausen's neurofibromatosis is a congenital anomaly due to maldevelopment of the neurectoderm and mesoderm. The disease is known to be commonly associated with other tumors of the neural system. We experienced a case in which two different types of spinal tumors (meningioma and schwannoma) appeared together with Von Recklinghausen's disease. The patient was a 54 year-old female. Her chief complaint was slowly progressive lumbar back pain of about a 10-year duration. She was admitted to our hospital after developing such clinical symptoms as paraparesis, bladder and rectal incontinence, and pain in the soles of her feet. The CT study demonstrated a massive tumor at the TH12-L2 levels accompanied with marked scalloping of the posterior vertebral body. The tumor removed was, histologically, meningioma. During surgery, another small bean-size tumor was incidentally found originating from the dorsal root, and it was identified by histological study as typical schwannoma. It has been reported that the incidence rate of spinal tumors in von Recklinghausen's disease is approximately 4%. Although a case has been reported in which different types of tumors developed in both the cranium and the spinal canal, our case as described above is considered extremely rare as far as we can find in reference literature. The pathogenic mechanism of vertebral scalloping as encountered in our case was thought to be based on interactions between hypoplasia of the supporting tissue and pressure generated by the tumor and CSF.
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PMID:[Two different spinal tumors (meningioma and schwannoma) with von Recklinghausen's disease in a case]. 211 59

Mapping of the EVI2 gene between the translocation breakpoints of two patients with neurofibromatosis type 1 (NF1), combined with the likely role of its murine homolog in neoplastic disease, implicates EVI2 as a possible candidate for the NF1 gene. We report here the expression of a 1.6-kb EVI2 transcript in normal human brain and peripheral blood mononuclear cells. Sequencing studies predict an EVI2 protein of 232 amino acids that contains an N-terminal signal peptide, an extracellular domain with five potential glycosylation sites, a single hydrophobic transmembrane domain with a leucine zipper, and a hydrophilic cytoplasmic domain. These features are all well-conserved with respect to the mouse Evi-2 protein and are consistent with the hypothesis that EVI2 is a membrane protein that may complex with itself and/or other proteins within the membrane, perhaps to function as part of a cell-surface receptor. In the course of these studies we have also identified three other transcripts (classes of cDNAs) from the NF1 region. Two of these transcripts map between the NF1 translocation breakpoints; the remaining transcript maps just outside this region.
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PMID:Identification and characterization of transcripts from the neurofibromatosis 1 region: the sequence and genomic structure of EVI2 and mapping of other transcripts. 211 66

A neurofibroma originated from the intrathoracic vagal nerve was presented. A 26-year-old male was found to have an abnormal shadow in the right chest filed on a routine examination. He was complicated with Von Recklinghausen's disease and showed multiple "cafe au lait" spots over his extremities and trunk but no subcutaneous mass. A block resection of the mass was carried for the mediastinal tumor. The tumor was arising from the right intrathoracic vagal nerve which located just below the origin of recurrent nerve and was measured 3 X 3 X 6 cm. Histological examination of the specimen revealed neurofibroma. His postoperative course was uneventful. A brief review in Japan was made on 22 cases collected from the literature.
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PMID:[Neurofibroma originated from the intrathoracic vagal nerve in a patient with von Recklinghausen's disease--a case report]. 212 Mar 72

We report a case of giant plexiform neurofibromatosis revealed by a sensori-motor, axo-myelinic polyneuropathy. Only the lumbar and sacral spinal nerves were involved in this peripheral form of Von Recklinghausen's disease. The polyneuropathy was due to compression of the nervous fibers by the neurofibromatous tumors. Ultrasonography DTPA 99 m Technetium scintigraphy, CT and MRI were the diagnostic procedures. MRI proved superior to CT in demonstrating the extent of the lesions. Biopsy confirmed the diagnosis. This form of neurofibromatosis did not involve the central nervous system, cranial nerves of cervicothoracic spinal nerves and roots; nor was there any visceral involvement, particularly endocrine neoplasia.
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PMID:[Peripheral neurofibromatosis and involvement of lumbosacral nerves. Value of imaging]. 212 24


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