Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035412 (rhabdomyosarcoma)
 6,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The immunohistochemical distribution of alpha and beta subunits of S-100 protein (S-100 alpha, S-100 beta, respectively) in 138 cases of human brain tumors was investigated by the avidin-biotin immunoperoxidase method. Brain tumors can be divided into four groups: group 1 [S-100 alpha (+) and/or S-100 beta (+)]; astrocytoma, glioblastoma, ependymoma, subependymoma, oligodendroglioma, choroid plexus papilloma, gangliocytoma, meningioma, chordoma, malignant melanoma. Group 2 [S-100 alpha (+) and S-100 beta (-)]; pineoblastoma, pituitary adenoma, craniopharyngioma, rhabdomyosarcoma. Group 3 [S-100 alpha (-) and S-100 beta (+)]; acoustic Schwannoma. Group 4 [S-100 alpha (-) and S-100 beta (-)]; medulloblastoma malignant lymphoma, germinoma. The S-100 beta immunoreactivity pattern in brain tumors was similar to those obtained using conventional anti-S-100 protein sera. In the first group of brain tumors both the number of positively stained tumor cells and the staining intensity were generally greater for S-100 beta than for S-100 alpha with a few exceptions including one gemistocytic astrocytoma, one subependymoma, one malignant melanoma, and some cases of glioblastomas. As to the relationship between malignancy and S-100 protein in glioma, S-100 beta immunoreactivity decreased according to degree of malignancy, while that of S-100 alpha varied, suggesting a heterogeneity of tumor cells in glioblastomas. Immunostaining for S-100 alpha and S-100 beta might become a useful diagnostic procedure in brain tumors and may give us more detailed and precise data of S-100 protein in brain tumors.
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PMID:Immunohistochemical study on the distribution of alpha and beta subunits of S-100 protein in brain tumors. 188 40

The radiologist must have a thorough knowledge of the normal anatomy and the pathologic spectrum of the skull base to determine the extent of abnormality and to help plan the surgical approach. The authors describe and present examples of congenital, benign, and malignant lesions that affect this region, including cephalocele, fracture, fistula, juvenile angiofibroma, meningioma, chordoma, pituitary adenoma, chondrosarcoma, nasopharyngeal carcinoma, and rhabdomyosarcoma. Metastatic, infectious, and other miscellaneous processes are also discussed. Imaging strategies with computed tomography and magnetic resonance imaging to aid in the diagnosis are suggested.
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PMID:CT and MR imaging of the central skull base. Part 2. Pathologic spectrum. 221 72

Sinonasal neoplasms and neoplasm-like proliferations composed of light microscopically poorly differentiated or undifferentiated, small- to medium-sized cells cause considerable diagnostic confusion. Lesions in this category include lymphoepithelioma (undifferentiated carcinoma), olfactory neuroblastoma, small-cell undifferentiated (oat cell) carcinoma, sinonasal undifferentiated carcinoma, malignant melanoma, pituitary adenoma, lymphoid hyperplasia, malignant lymphoma, plasmacytoma, lymphomatoid granulomatosis, rhabdomyosarcoma, mesenchymal chondrosarcoma, small cell osteosarcoma, Ewing's sarcoma, and synovial sarcoma. Many of these lesions can be definitively diagnosed based on light microscopic features alone, but, in some instances, additional techniques such as immunohistochemistry are of value. The authors review the pertinent clinicopathologic features of the above lesions, with emphasis on light microscopic, immunohistochemical, and ultrastructural features of particular utility in differential diagnosis.
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PMID:"Undifferentiated" neoplasms of the sinonasal region: differential diagnosis based on clinical, light microscopic, immunohistochemical, and ultrastructural features. 269 5

The sinonasal region is known to harbor several types of tumors that belong to the general category of "small" round cell tumors and offer considerable diagnostic challenges. This study evaluated 33 cases of such tumors by electron microscopy to characterize their ultrastructural features in conjunction with immunohistochemistry, in an attempt to define diagnostic criteria of various types. Electron microscopy was useful in the proper classification of tumors in 27 cases: esthesioneuroblastoma (EN), 12; undifferentiated carcinoma, 6; melanoma, 3; lymphoma, 3; melanotic neuroectodermal tumor, 1; rhabdomyosarcoma, 1; and pituitary adenoma, 1. In the remaining six cases, the ultrastructural features were those of poorly differentiated carcinomas. They usually exhibited some epithelial characteristics as well as neuroendocrine features by immunohistochemistry and electron microscopy. These tumors could be best described as poorly differentiated neuro-endocrine carcinomas (malignant neuroepitheliomas). The most controversial diagnostic problems existed between the tumors categorized as esthesioneuroblastomas and neuroendocrine (NE) carcinomas. Esthesioneuroblastomas were characterized by uniform round nucleated cells with variable amounts of dendritic processes containing numerous dense core granules ranging from 150 to 350 nm in the perikarya and dendritic processes. Dendritic processes contained longitudinally arranged neural tubules and revealed an occasional synaptic junction. In three of the 12 cases of EN, cells with the appearance of sustentacular cells were recognized by electron microscopy. The NE carcinomas usually consisted of closely packed round cells with scanty cytoplasm that lacked any feature of neuroblastic cells. The tumor cells in this category often were epithelioid in appearance and exhibited a varying degree of cytokeratin positivity. Neuron-specific enolase was also positive in all cases, further suggesting their neuroepithelial nature. The greatest difference between EN and NE carcinomas was the absence of sustentacular cells in NE carcinomas. Immunohistochemical and electron microscopic studies are essential in the differential diagnosis of EN and NE carcinomas, because their microscopic appearance is very similar. The study indicates that EM is useful in the diagnostic categorization of sinonasal tumors of uncertain nature, particularly when it is used in conjunction with immunohistochemistry.
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PMID:Usefulness of electron microscopy in the diagnosis of "small" round cell tumors of the sinonasal region. 748 11

Astrocytic tumors occasionally arise in the central nervous system following radiotherapy. It is not clear if these gliomas represent a unique molecular genetic subset. We identified nine cases in which an astrocytoma arose within ports of previous radiation therapy, with total doses ranging from 2400 to 5500 cGy. Irradiated primary lesions included craniopharyngioma, pituitary adenoma, Hodgkin's lymphoma, ependymoma, pineal neoplasm, rhabdomyosarcoma, and three cases of lymphoblastic malignancies. Patients ranged from 9 to 60 years of age and developed secondary tumors 5 to 23 years after radiotherapy. The 9 postradiation neoplasms presented as either anaplastic astrocytoma (3 cases) or glioblastoma multiforme (6 cases). Two of the latter contained malignant mesenchymal components. We performed DNA sequence analysis, differential polymerase chain reaction (PCR), and quantitative PCR on DNA from formalin-fixed, paraffin-embedded tumors to evaluate possible alterations of p53, PTEN, K-ras, EGFR, MTAP, and p16 (MTS1/CDKN2) genes. By quantitative PCR, we found EGFR gene amplification in 2 of 8 tumors. One of these demonstrated strong immunoreactivity for EGFR. Quantitative PCR showed chromosome 9p deletions including p16 tumor suppressor gene (2 of 7 tumors) and MTAP gene (3 of 7). Five of 9 tumors demonstrated diffuse nuclear immunoreactivity for p53 protein. Sequencing of the p53 gene in these 9 cases revealed a mutation in only one of these cases, a G-to-A substitution in codon 285 (exon 8). Somewhat unexpectedly, no mutations were identified in PTEN, a commonly altered tumor suppressor gene in de novo glioblastoma multiformes. Unlike some radiation-induced tumors, no activating point mutations of the K-ras proto-oncogene or base pair deletions of tumor suppressor genes were noted. These radiation-induced tumors are distinctive in their high histological grade at clinical presentation. The spectrum of molecular genetic alterations appears to be similar to that described in spontaneous high grade astrocytomas, especially those of the de novo type.
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PMID:Molecular genetic alterations in radiation-induced astrocytomas. 1032 96

As an anatomical interface between various tissues, the skull base harbors an exceptionally broad variety of neoplasms, some of which pose a major challenge for surgical pathology. The characterization of distinct immunohistochemical expression profiles and the identification of molecular genetic alterations associated with different tumor entities have significantly advanced this field. The new World Health Organization (WHO) classification of tumors of the nervous system lists 15 histopathological variants of meningioma. Of clinical importance are those entities that carry an increased risk of recurrence and a poor prognosis, i.e., the atypical meningioma (WHO grade II), clear-cell meningioma (WHO grade II), chordoid meningioma (WHO grade II), rhabdoid meningioma (WHO grade III), papillary meningioma (WHO grade III), and anaplastic meningioma (WHO grade III). Diagnostic criteria for atypical and anaplastic meningioma variants have now been stringently defined. The differential diagnosis of meningiomas includes hemangiopericytoma, hemangioblastoma, solitary fibrous tumor, sarcomas, and chordoid neoplasms. Recent data highlight the importance of distinguishing chordoma and chondrosarcoma of the skull base since chondrosarcomas show a significantly better clinical outcome. Among the less common, aggressive tumor entities in this anatomical region, infiltrating pituitary adenoma/pituitary carcinoma, superficial malignant gliomas, rhabdomyosarcoma, olfactory neuroblastoma, various sarcomas, and malignant lymphoma must be considered. Profiles of molecular genetic alterations have been established for several of these neoplasms and may facilitate the differential diagnosis. This review summarizes recent developments in the histopathological characterization, classification, and molecular pathology of neoplasms arising at the skull base.
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PMID:New developments in the pathology of skull base tumors. 1135 65

Modern imaging techniques have great importance in the diagnosis and therapy of skull-base pathologies. Many of these lesions, especially in relation to their specific location, can be evaluated using CT and MR imaging. Tumors commonly found in the anterior skull base include carcinoma, rhabdomyosarcoma, esthesioneuroblastoma and meningioma. In the central cranial fossa, nasopharyngeal carcinoma, metastases, meningioma, pituitary adenoma and neurinoma have to be considered. The most common neoplasms of the posterior skull base, including the CP angle, are neurinoma, meningioma, nasopharyngeal carcinoma, chordoma and paraganglioma. One major task of imaging is the evaluation of the exact tumor extent as well as its relationship to the neighboring neurovascular structures. The purpose of this review is to recapitulate the most important anatomical landmarks of the skull base. The typical imaging findings of the most common tumors involving the skull base are also presented.
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PMID:[Skull base tumors]. 1609 41

Sinonasal tract neoplasms composed of light microscopically seemingly "undifferentiated" small round cells often generate considerable diagnostic difficulty. Although the careful review of H&E-stained sections remains of critical and central importance in this evaluation, the recent improvements in the immunohistochemical diagnostic armamentarium and molecular diagnostic techniques applicable to paraffin-embedded tissue samples may add diagnostically valuable information. Accordingly, this review will discuss the differential diagnosis of undifferentiated small blue cell tumors of the sinonasal tract based on the light microscopic and clinical features and, as needed, the results of these ancillary studies. Tumors discussed include olfactory neuroblastoma, sinonasal undifferentiated carcinoma, small cell undifferentiated (neuroendocrine) carcinoma, undifferentiated (lymphoepithelioma-like) carcinoma, malignant melanoma, pituitary adenoma, Ewing sarcoma/peripheral neuroectodermal tumor, rhabdomyosarcoma, mesenchymal chondrosarcoma, small cell osteosarcoma, synovial sarcoma, extranodal natural killer/T-cell lymphoma, nasal type, and extramedullary plasmacytoma.
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PMID:"Undifferentiated" small round cell tumors of the sinonasal tract: differential diagnosis update. 1646 21

Intrasellar rhabdomyosarcoma is rare, and when arising in collusion with an unrelated entity, can present a diagnostic pitfall. We describe a case of a 56-year-old woman who presented with right eye ptosis and a pituitary mass, which was resected and diagnosed as atypical pituitary adenoma. Because of residual disease and atypical pathology, the patient received adjuvant radiation. Tumor recurrence was noted after 5 months, and a second resection was performed. Nests of atypical pituitary adenoma cells within an exuberant spindle cell stroma were noted, with areas of presumed radiation necrosis. A second recurrence prompted a third resection. After expert consultation and additional immunohistochemical stains for muscle markers, a diagnosis was rendered of primary rhabdomyosarcoma arising in association with a pituitary adenoma. Despite its rarity, a high index of suspicion for rhabdomyosarcoma arising within a pituitary adenoma should be maintained in cases of atypical pituitary adenoma with a stromal response.
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PMID:Primary Sellar Rhabdomyosarcoma Arising in Association With a Pituitary Adenoma. 2742 70

One of the most challenging diagnostic categories within tumors of the sinonasal tract is the small round blue cell tumors. Biopsies are usually small and limited, resulting in considerable diagnostic difficulty for practicing surgical pathologists. These tumors share several overlapping histologic and immunophenotypic findings while also showing considerable variation within and between cases. Specific tumor site of origin, imaging findings, and clinical findings must be combined with the histology and pertinent ancillary studies if the correct diagnosis is to be reached. Discrimination between neoplasms is critical as there are significant differences in therapy and overall outcome. It is important to have a well developed differential diagnosis for this category of tumors, where each of the diagnoses is considered, evaluated, and either confirmed or excluded from further consideration. In an undifferentiated tumor, showing a small round blue cell morphology, using the mnemonic 'MR SLEEP' helps to highlight tumors to consider: melanoma, mesenchymal chondrosarcoma, rhabdomyosarcoma, sinonasal undifferentiated carcinoma, squamous cell carcinoma (including NUT carcinoma), small cell osteosarcoma, lymphoma, esthesioneuroblastoma (olfactory neuroblastoma), Ewing sarcoma/primitive neuroectodermal tumor, pituitary adenoma, and plasmacytoma. A panel of pertinent immunohistochemistry studies, histochemistries and/or molecular tests should aid in reaching a diagnosis, especially when taking the pattern and intensity of reactions into consideration.
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PMID:Small round blue cell tumors of the sinonasal tract: a differential diagnosis approach. 2806 Mar 73


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