Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0268596 (EMA)
 2,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Astroblastomas are uncommon brain tumors whose classification and histogenesis have been debated. Precise criteria for diagnosis have been described only recently, but have not found wide acceptance. We report the clinical, radiographic, and histopathologic features of 20 astroblastomas, and the chromosomal alterations in seven cases as detected by comparative genomic hybridization (CGH). The tumors occurred both in children and young adults (average age, 14 years), most often as well circumscribed, peripheral, cerebral hemispheric masses. Radiographically, the lesions were contrast-enhancing and solid, often with a cystic component. All were characterized histologically by astroblastic pseudorosettes, and most displayed prominent perivascular hyalinization, regional hyaline changes, and pushing borders in regard to adjacent brain. Tumor cells were strongly immunoreactive for S-100 protein, GFAP, and vimentin. Staining for EMA was focal. Ten of 20 astroblastomas were classified as "well differentiated" and 10 were classified as "malignant," largely on the basis of hypercellular zones with increased mitotic indices, vascular proliferation, and necrosis with pseudopalisading. All 10 well differentiated lesions and 8 of 10 malignant lesions were completely resected. None of the well differentiated astroblastomas recurred within the limited follow-up period. Three malignant astroblastomas recurred, including two incompletely resected tumors, and one that had been totally resected. One patient died of disease following recurrence. The most frequent chromosomal alterations detected by CGH were gains of chromosome arm 20q (4/7 tumors) and chromosome 19 (3/7). The combination of these gains occurred in three, including two well differentiated and one malignant astroblastoma. Other alterations noted in two tumors each were losses on 9q, 10, and X. These chromosomal alterations are not typical of ependymoma or infiltrating astrocytic neoplasms, and suggest that astroblastomas may have a characteristic cytogenetic profile in addition to their distinctive clinical, radiographic, and histopathologic features.
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PMID:Astroblastoma: clinicopathologic features and chromosomal abnormalities defined by comparative genomic hybridization. 1088 53

Astroblastoma is a rare, enigmatic tumor of the central nervous system (CNS) which shares some clinicopathologic aspects with other CNS tumors, especially ependymoma. To further clarify the nature of astroblastoma, we performed clinicopathologic and molecular genetic studies on eight cases of astroblastoma. The median age of the patients was 14.5 years, ranging from 5 to 60 years, and seven of the patients were female. All tumors arose in the cerebral hemisphere and radiologically appeared to be well-bordered, nodular tumors often associated with cystic areas and contrast-enhancement. Six of the seven patients with prognosis data survived without recurrences during the follow-up periods ranging from six to 76 months. One patient had multiple recurrences and died six years later. All tumors exhibited salient microscopic features, such as being well demarcated from the surrounding brain tissue, perivascular arrangement of epithelioid tumor cells (represented by "astroblastic" pseudorosettes, trabecular alignment, and pseudopapillary patterns), and hyalinized blood vessels. Immunoreactivity for GFAP, S-100 protein, Olig2, and EMA was variably demonstrated in all tumors, and IDH1 R132H and L1CAM were negative. Array comparative genomic hybridization revealed numerous heterozygous deletions on chromosome X in the four tumors studied, and break-apart fluorescence in situ hybridization demonstrated rearrangement of MN1 in five tumors with successful testing. The characteristic clinicopathologic and genetic findings support the idea that astroblastoma is distinct from other CNS tumors, in particular, ependymoma. In addition, MN1 rearrangement and aberrations of chromosome X may partly be involved in the pathogenesis of astroblastoma.
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PMID:Astroblastoma: a distinct tumor entity characterized by alterations of the X chromosome and MN1 rearrangement. 2899 Jul 8

Astroblastoma is a rare neuroepithelial tumor most commonly seen in children and young adults. Due to its rarity, this tumor can be easily misdiagnosed as its classification, histogenesis and therapeutic management are still being discussed. We report the case of a 21 year old man, who presented at the Emergency Room for loss of consciousness. He reported a history of headaches, vomiting and decreased visual acuity. The CT and MRI showed a left temporoparietal solid-cystic mass with heterogeneous enhancement and perilesional edema. The patient underwent a total mass resection. On histopathological examination, tumor cells were organized in perivascular pseudorosettes which are typically encountered in astroblastoma, without neither necrosis nor endothelial hyperplasia. They had broad processes and rounded nuclei without any mitotic activity. Immunochemistry stains confirmed the diagnosis by showing a positive reactivity for GFAP, EMA, vimentin and S100. Astroblastoma is a rare glial tumor of uncertain origin. Clinical presentation and imaging are nonspecific. Therefore, its diagnosis is based on histopathologic findings: typical perivascular pseudorosettes. However, similar histological pattern may be seen in other glial neoplasms. In the 2016 WHO Classification, astroblastoma is among the "other glial neoplasms" without a grading system. So far, there are no reliable prognosis factors for this tumor; however, two entities have been described: well differenciated astroblastoma (considered as low grade) and anaplastic/malignant astroblastomas (considered as high grade). Gross total resection is the treatment of choice for astroblastomas. Adjuvant therapy is still controversial. This case illustrates a cerebral tumor which is rarely encountered in practice and that can cause diagnostic problems and subsequently, inadequate treatment.
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PMID:[Astroblastoma: A rare glial tumor]. 3048 65