Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pleomorphic xanthoastrocytoma (PXA) is a low-grade glioma that may recur as a malignant diffuse astrocytoma such as glioblastoma (GBM). While the molecular genetic basis of diffuse astrocytomas has been studied extensively, PXAs have not been analyzed in detail. We, therefore analyzed DNA from archival primary and recurrent PXAs from eight patients (three grade II PXAs without recurrence, one grade II PXA with recurrence as grade II PXA, two grade II PXAs with progression to GBM, and two grade III anaplastic PXAs with recurrence as grade III anaplastic PXA or GBM) for genetic changes associated with diffuse astrocytomas. Single-strand conformation polymorphism analysis of p53 exons 5-8 revealed migration shifts in two cases, one primary PXA without recurrence and one recurrent grade II PXA in which the primary tumor did not show a shift. DNA sequencing showed two missense mutations in codons 220 (exon 6) and 292 (exon 8), respectively, mutations which have not been previously noted in astrocytomas. Differential polymerase chain reaction analysis demonstrated epidermal growth factor receptor gene amplification in only one tumor, a GBM without allelic loss of chromosome 10 that was the second GBM recurrence of an initial grade II PXA. Loss of heterozygosity studies on tumors from five patients, using three microsatellite polymorphisms on chromosome 10q and three on chromosome 19q, did not disclose allelic loss in any recurrent tumor. These findings suggest that the genetic events that underlie PXA formation and progression may differ significantly from those involved in diffuse astrocytoma tumorigenesis.
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PMID:Molecular genetic alterations in pleomorphic xanthoastrocytoma. 883 42

Pleomorphic xanthoastrocytoma has been generally conceived to be in a benign nature, showing a relatively favorable prognosis. Apoplectic attack attributable by massive hemorrhage in this distinct form of the supratentorial glioma is an exceedingly rare event. A 61-year-old female presented with a sudden onset of generalized tonic--clonic convulsion. CT and MRI disclosed the presence of a tumor composing of massive intra-tumoral hemorrhage filling the cyst associated with mural nodule in the left frontotemporal lobe. At surgery, the subpial mass involving hematoma was well marginated and slightly adherent to the dura mater. It could be removed totally and proved to be a pleomorphic xanthoastrocytoma. The unusual hemorrhagic presentation of this typically benign entity is extremely rare and is thought to be intra-tumoral bleeding in this case, since subarachnoid hemorrhage was absent.
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PMID:A case of pleomorphic xanthoastrocytoma presenting with massive tumoral hemorrhage. 1629 92

Pleomorphic xanthoastrocytoma (PXA) is a rare superficial glioma that predominates in the young and has good prognosis. A long history of repeated seizures is commonly associated with PXA, which is frequently observed in neuroimaging scans as a solid-cystic, contrast-enhancing lesion. We report a case in which PXA diagnosis was favored by its histological features, such as pleomorphic multinucleated giant cells, with disproportionately few mitoses and necrotic areas. An eye-catching feature was widespread, pale-staining, circumscribed deposits in the cytoplasm of tumor cells, which turned out to be glycogen upon histochemical and electron-microscopical examination. The stored material was strongly PAS-positive and digested by diastase, and had a finely granular ultrastructural appearance. No evidence of lipid droplets was found on oil-red-O staining. The tumor was immunoreactive for glial fibrillary acidic protein and vimentin. Many cells were positive for CD34 on the external membrane, a feature which has been described in chronic CNS lesions associated with epilepsy. Intracytoplasmic immunostaining for EGFR was observed in most tumor cells, which might have favored neoplastic proliferation. Nuclear immunolabeling for p53 protein was rare and does not support a major role for p53 mutation in PXA tumorigenesis. Intracellular accumulation of glycogen in glial tumors is uncommon and may originate from abnormalities in carbohydrate metabolic pathways.
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PMID:Temporal pleomorphic xanthoastrocytoma with glycogen accumulation--case report. 1866 39

Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic neoplasm of the brain. Some PXAs are accompanied by anaplastic features and are difficult to manage because of frequent recurrences that lead to early death. No previous reports have demonstrated consistent efficacy of adjuvant radiotherapy or chemotherapy for this disease. We report a case of PXA with anaplastic features treated with stereotactic irradiation (STI) that resulted in long-term control of repeatedly recurring nodules throughout the neuraxis. A 47-year-old woman presented with an epileptic seizure due to a large tumor in the right frontal lobe. The tumor was resected and diagnosed as PXA with anaplastic features. Sixteen months later, a relapse at the primary site was noted and treated with stereotactic radiosurgery using Gamma Knife. Two years later, the patient developed a tumor nodule in the cervical spinal cord that histologically corresponded to a small-cell glioma with high cellularity and prominent MIB-1 (mindbomb homolog 1) labeling. In the following months, multiple nodular lesions appeared throughout the CNS, and STI was performed six times for eight intracranial lesions using Gamma Knife and twice using a linear accelerator, for three spinal cord lesions in total. All lesions treated with STI were well controlled, and the patient was free from symptomatic progression for 50 months. However, diffuse dissemination along the craniospinal axis eventually progressed, and she died 66 months after initial diagnosis. Autopsy showed that the nodules remained well demarcated from the surrounding nervous system tissue. STI may be an effective therapeutic tool for controlling nodular dissemination of PXA with anaplastic features.
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PMID:Long-term control of disseminated pleomorphic xanthoastrocytoma with anaplastic features by means of stereotactic irradiation. 1916 34

With the exception of oligoastrocytoma, mixed gliomas are rarely encountered, and the astrocytic component of mixed oligoastrocytoma is almost always fibrillary and diffusely infiltrative. Pleomorphic xanthoastrocytoma (PXA) has occasionally been described in conjunction with ganglioglioma, as well as in 1 case of oligodendroglioma. In this latter case, described by Perry et al., 1p/19q codeletions were not detected. The authors report on a 25-year-old woman with a combined PXA/oligodendroglioma in which concurrent 1p/19q codeletions were detected in the oligodendroglial component only. The patient presented with a 1-month history of headaches. Neuroimaging revealed a heterogeneous left temporal mass with focal enhancement, cystic changes, hemorrhage, and left-to-right midline shift. The patient underwent a craniotomy and gross-total resection. Pathological examination revealed a glial tumor composed of 2 apparently distinct components. The largest component exhibited a prominent fascicular, reticulin-rich, spindle cell arrangement admixed with areas of highly pleomorphic cells, with bizarre cytological features reminiscent of PXA. A smaller component was composed of cellular sheets and lobules of oligodendroglial cells. Both components were characterized by anaplastic features. Dual-color fluorescence in situ hybridization for 1p/19q codeletions was performed. Only the oligodendroglial component showed the combined 1p/19q deletions. This case represents the first instance in which PXA has been reported in conjunction with an oligodendroglioma exhibiting the "molecular signature" characteristic of oligodendroglial neoplasms. The different genetic alterations seen in the 2 components of this neoplasm argue in favor of a "collision tumor" rather than a mixed glioma of the same genotype.
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PMID:Pleomorphic xanthoastrocytoma and oligodendroglioma: collision of 2 morphologically and genetically distinct anaplastic components. 2121 37

Pleomorphic xanthoastrocytoma (PXA) is a rare benign tumor that is usually located in the superficial cerebral hemisphere. Most reports of PXAs have included only a single case or small series. Therefore, the data with respect to the natural history of this tumor are fragmentary. We report a case of a PXA in the unusual location of the right lateral ventricle with extensive subarachnoid dissemination. To our knowledge, this is a rare case of PXA in the lateral ventricle. In addition, extensive subarachnoid space dissemination of this distinctly benign type of glioma is exceedingly rare. In our case, there was meningeal dissemination and metastases to the bilateral trigeminal nerves and oculomotor nerves. The neuroradiographic features, tumor location, and dissemination were reviewed.
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PMID:Pleomorphic xanthoastrocytoma in the lateral ventricle with extensive subarachnoid dissemination: report of a case and review of the literature. 2234 May 80

Pleomorphic xanthoastrocytoma (PXA) is a rare glioma. This paper aimed to analyze magnetic resonance imaging (MRI) characteristics in a series of patients diagnosed with PXA. We analyzed MRI findings in 9 patients with histopathologic diagnosis of PXA in our department over the last 12 years. The mean age of patients was 27.3 years. Cortical location was observed in all cases. The lesion imaging was solid-cystic in six cases. In eight cases, the solid component presented hypo or isointense on T1 and iso or hyperintense on T2. Contrast enhancement in the solid component was observed in eight cases. The observed imaging pattern of PXA was superficial location with leptomeningeal involvement, solid-cystic pattern and contrast enhancement in the solid component. We should consider that the association between PXA and other cortical tumors may occur, particularly, with gangliogliomas, which tend to be the main differential diagnosis in MRI.
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PMID:Pleomorphic xanthoastrocytoma: magnetic resonance imaging findings in a series of cases with histopathological confirmation. 2333 59

Pleomorphic xanthoastrocytoma (PXA) is a World Health Organization Grade 2 glioma that is uncommon (<1 % all adult gliomas) and seen primarily in children and young adults. PXA has been demonstrated to manifest the V600E BRAF mutation in nearly 70 % of all tumors, a mutation that constitutively activates the BRAF/MEK signaling pathway. Assess response and toxicity of a BRAF inhibitor, vemurafenib, in recurrent PXA manifesting the V600E mutation. Four adults [2 males; 2 female: median age 45 years (range 34-53)] with surgery, radiation and alkylator refractory recurrent PXA demonstrating the BRAF mutation (V600E) were treated with vemurafenib. A cycle of vemurafenib was defined as 4 weeks of continuous therapy. All toxicities seen were grade 2 and included arthralgia, photosensitivity, fatigue and nausea (1 patient each). The median number of cycles of therapy was 5 (range 2-10). Radiographic response was progressive disease in 1, stable disease in 2 and partial response in 1. Median progression free survival was 5 months (range 2-10 months). Median overall survival was 8 months (range 4-14 months). In this small retrospective series of select patients with recurrent PXA manifesting the BRAF V600E activating mutation, vemurafenib appears to have single agent activity with manageable toxicity. Confirmation in a larger series of similar patients is required.
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PMID:Salvage therapy with BRAF inhibitors for recurrent pleomorphic xanthoastrocytoma: a retrospective case series. 2375 28

Pleomorphic xanthoastrocytoma (PXA) is a rare, low-grade glioma (World Health Organization Grade II) that most often presents in the first two decades of life. We summarize and present our institutional experience in the management of these tumors. All patients managed for PXA at the University of California San Francisco were retrospectively identified through chart review. Patient demographics, tumor characteristics, management, and follow-up were extracted using medical records. Primary endpoints were overall (OS) and progression-free survival (PFS). In total, nineteen patients were treated for PXA from 1993-2011. Clinical data were available for analysis in 18 patients. Median OS was 209.0 months after date of surgery, with both 5 year and 10 year survival rates of 94%. In this patient cohort, tumor grade (p=0.07), age (p=0.32), and extent of resection (p=0.58) did not predict OS. The majority of tumors (78%) recurred. Median PFS was 21.7 months, with 5 year and 10 year recurrence-free rates of 28% and 22%. On univariate analysis, tumor grade (p=0.01), but not age (p=0.51), size (p=0.30), or extent of resection (p=0.21), was the only covariate predictive of PFS. In patients presenting with higher tumor grade, however, earlier recurrence was demonstrated. Furthermore, the majority of recurrences (36%) occurred within the first 6 months post-operatively, which indicates the need to closely follow patients for that time.
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PMID:Pleomorphic xanthoastrocytomas: institutional experience of 18 patients. 2495 Sep 6

Pleomorphic xanthoastrocytoma (PXA) has rarely been reported in combination with infiltrating glioma, historically interpreted as a "collision tumor." Isocitrate dehydrogenase 1 (IDH1) and BRAF V600E mutations are usually not concurrent. The former is typical of adult infiltrating gliomas, and the latter is identified in a variety of primary central nervous system neoplasms, including PXA, ganglioglioma, pilocytic astrocytoma, and rarely infiltrating gliomas. We report the case of a 56-year-old man presenting with seizures and headaches. Magnetic resonance imaging revealed a large right temporal lobe mass with low T1 and high T2/FLAIR signal and a discrete contrast-enhancing focus. Histologically, the tumor showed 2 distinct components: an infiltrating astrocytoma harboring 5 mitoses/10 high-power fields and a relatively circumscribed focus, resembling PXA with, at most, 2 mitoses/10 high-power fields. No microvascular proliferation or necrosis was present in either component. The infiltrating astrocytoma component contained numerous axons, whereas the PXA-like component had sparse axons, as demonstrated by the neurofilament immunostain. Both components were positive for the mutant IDH1 R132H and showed loss of ATRX expression, whereas BRAF V600E was restricted to the PXA-like component. On sequencing of the 2 components separately after microdissection, both showed identical IDH1 R132H and TP53 R273C point mutations, whereas the BRAF V600E mutation was limited to the PXA-like component. These findings are consistent with clonal expansion of a morphologically distinct focus, harboring a private BRAF V600E mutation within an IDH1-mutant glioma. Intratumoral heterogeneity and clonal evolution, as seems to have occurred here, suggest reevaluation of "collision tumors" as a concept.
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PMID:Combined "Infiltrating Astrocytoma/Pleomorphic Xanthoastrocytoma" Harboring IDH1 R132H and BRAF V600E Mutations. 2641 24


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