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

Twenty-one intracranial subependymomas were reviewed with regard to presentation, diagnosis, operative findings, and long-term follow-up data. The histopathological features were critically reviewed, and deoxyribunucleic acid analysis was performed by flow cytometry. The patients' mean age was 48.5 years (range 32 to 72 years). In 14 cases the tumor was located in the fourth ventricle, in six within a lateral ventricle, and in one in the third ventricle with extension into the lateral ventricle. Radiographic characteristics included isodensity with minimal enhancement on computerized tomography, frequent dystrophic calcification, and isointensity on T1-weighted or slight hyperintensity on T2-weighted magnetic resonance images. The predominant histological features in all cases were those of classic subependymoma. Nonetheless, pathological examination showed a minor (less than 20%) ependymoma component in five cases, significant cytological atypia in seven, mitoses in 11, endothelial prominence in four, and focal hemorrhage-associated necrosis in two. Flow cytometry revealed a diploid pattern in 12 patients, tetraploidy in two, and aneuploidy in one. Two patients died in the perioperative period. Of the remaining 19, 12 underwent gross total resection (two of whom received postoperative irradiation) and seven underwent subtotal resection (five of whom received irradiation). None of the 12 non-irradiated patients developed tumor progression or died of direct tumor-related causes. Of the seven irradiated patients, follow-up imaging studies demonstrated their tumors to be radioresponsive, particularly with doses of 5000 cGy or greater. Despite the presence of cytological atypia and mitotic activity in the majority of cases, the prognostic effects of such factors as tumor location and the extent of surgical resection outweighed those of the standard histopathological parameters. Routine postoperative irradiation is not recommended, but should be reserved for cases with a symptomatic residual or recurrent subependymomas following surgery.
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PMID:Symptomatic subependymoma: a clinicopathological and flow cytometric study. 188 76

Advances in the surgical management of central nervous system neoplasms have been reported in several areas including the skull base, the spine and the stereotaxic applications in neurosurgery. A national survey of patterns of care for brain tumor patients contributed data on 11,185 patients, 97% of whom underwent surgery. Stereotaxic-guided craniotomies are providing added accuracy and shortened operative time and length of hospitalization, while the stereotaxic implantation of I125 seeds for recurrent high grade glioma has resulted in prolongation of survival between 54 and 81 weeks. Radiosurgery is being applied with increasing frequency and remarkable success in the management of skull base tumors, acoustic neuroma, and brain metastasis. The two prototypes used are the Gamma-knife and the linear accelerator-based multiple converging arcs technique. In the area of the skull base, significant anatomical details have been provided. Historical facts and clinical series related to the management of meningiomas and acoustic neuromas are reviewed. Spinal cord ependymoma is a surgically curable tumor as reported in a series of twenty-three patients followed for a mean of 62 months, and a randomized study has established the superiority of surgical resection for single brain metastasis as compared to the results obtained with radiation therapy alone.
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PMID:Neurosurgery issues in oncology. 189 15

The aim of the study was to evaluate the feasibility and possible contribution of silver stained nucleolar organizer regions (AgNORs) to prognostic considerations, in a series of 55 supratentorial gliomas: eight grade II astrocytomas, twelve grade III astrocytomas, thirty grade IV astrocytomas, two glioblastomas, one anaplastic oligodendroglioma, one oligodendroglioma and one ependymoma. Silver NORs (AgNORs) were demonstrated according to the method of Crocker et al. A difference between AgNOR sizes in peritumor and tumor tissue is noted. The mean NOR numbers in the tumor areas range from 0.871 to 2.677, without overlap between peritumor gliosis and glial tumors. A comparative analysis reveals significant correlations between the mean NOR number per nucleus and histological grading. This technique can play a practical role in the diagnosis and grading of tumors sampled by stereotactic biopsies: a count higher than 0.8 is highly suggestive of malignancy. In addition, the distribution of NORs may be important: intratumoral heterogeneity expresses various degrees of transcriptional activity between different glial tumors of the same grade. This technique provides information about the biological behaviour of glial tumors supplementary to that obtained from growth fraction analysis.
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PMID:[Value of the nucleolar organizers (AgNOR) in brain gliomas]. 192 77

To assess whether thallium-201 thallous chloride (Tl) can detect childhood tumors and whether diagnostic effectiveness improves with combined blood flow imaging, 28 children (1.0-18.6 years) were studied using single photon emission computed tomography (SPECT): Tl (1.3-1.8 mCi intravenously), followed in 13 of the patients by technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO; 8-18 mCi intravenously). Tl-uptake was markedly increased with histologically confirmed recurrent brain tumors (N = 12). Tl-avid tumors comprised several histologic types, including 6 astrocytomas/gliomas as well as nonastrocytic neoplasms, such as medulloblastoma and ependymoma. A questionable false-positive study was observed with a treated medulloblastoma. Tl failed to detect 5 tumors (i.e., 2 medulloblastomas, 1 ependymoma, 1 malignant schwannoma, and initially 1 low-grade astrocytoma). The sensitivity and specificity of 201Tl-SPECT for detection of childhood brain tumors was 76.9% and 93.3%, respectively. The mean tumor-to-normal brain ratio for Tl was 2.5 +/- 0.5 (N = 7). In some of the patients, 201Tl-SPECT allowed a more precise assessment of the functional state of the tumor than was possible with computed tomography and magnetic resonance imaging. HMPAO distribution was variously normal, increased or decreased at the site of tissue abnormality, and abnormal blood flow was demonstrated in the remaining neuraxis, in 3 of the 7 patients. Changes in tissue perfusion did not correlate with Tl findings, but were evaluated in only one false-negative study.
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PMID:201Tl/99mTc-HMPAO SPECT imaging of treated childhood brain tumors. 193 Apr 15

Genomic DNA from 51 primary human brain tumors was screened for the presence of mutations in the tumor suppressor gene, p53, using the polymerase chain reaction and single strand conformation polymorphism analysis, followed by direct DNA sequencing. Mutations leading to an amino acid change were found in 2 of 17 (12%) oligodendrogliomas and 2 of 19 (11%) medulloblastomas but none of 15 ependymomas. Sites of mutations were in exon 5 (codon 141), exon 6 (codon 193 and 213), and exon 7 (codon 246). In addition, there were silent mutations in exon 6 (codon 213) in one oligodendroglioma and in one ependymoma. This study points to the possible role of the p53 tumor suppressor gene in some central nervous system neoplasms of divergent histogenesis.
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PMID:p53 mutations in nonastrocytic human brain tumors. 193 79

A 2.5-year-old child who had undergone nearly total resection of an infratentorial ependymoma demonstrated a new enhancing lesion on the undersurface of the right cerebellar hemisphere 7 weeks after the initiation of adjuvant chemotherapy. The residual primary tumor demonstrated continued regression during chemotherapy, and magnetic resonance imaging of the spine and cytopathological examination of the cerebrospinal fluid showed no evidence for other sites of metastatic tumor. Because of the unusual anatomic and temporal characteristics of this lesion and despite radiographic criteria highly suspicious for a metastatic lesion, a biopsy was performed, revealing histological evidence of an inflammatory process.
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PMID:Inflammatory lesion mimicking a metastatic ependymoma. 194 48

A mediastinal ependymoma in a 35-year-old Caucasian woman is reported. The tumor was located in a paravertebral posterior mediastinal location. No continuity with the spinal canal or with the lung was identified. The diagnosis was confirmed by immunoperoxidase staining for glial fibrillary protein and by the presence of cilia within intracytoplasmic vacuoles. To the best of our knowledge, this is the second reported case of ependymoma in this location.
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PMID:Mediastinal ependymoma. 198 85

Neuraxis radiation therapy (RT) for primary intracranial tumors is associated with major late effects if administered to very young children. To control residual tumor and to delay RT, we treated eight young children (median age 6.5 months) with primary central nervous system (CNS) tumors using combination chemotherapy: cisplatin, 20 mg/M2/day plus VP-16, 75 mg/M2/day i.v. for 5 days, given q. 3-6 weeks for 8 cycles. The tumors were medulloblastoma (one), malignant ependymoma (two), primitive neuroectodermal tumor PNET (two), malignant glioma (two), astrocytoma (one). Six had measurable disease; three had positive cerebrospinal fluid (CSF) cytopathology. All patients with measurable tumor had initial objective responses (three) complete response [CR], one partial response [PR], two minor response [MR], including cytopathology (three CR of three) and metastatic deposits (two CR of two). One patient relapsed during chemotherapy. Median time to disease progression was 17.5 months; median survival was 34 months. Three patients, none of whom received RT, have prolonged progression-free intervals of 47-67 months to date. Neurodevelopmental progress continued during and after chemotherapy. Chemotherapy toxicity was mild. Median neutrophil nadir was 312/mm3, platelets 72,000. Fever during neutropenia occurred in six of 61 courses. Moderate high-frequency auditory losses were detected in three patients, and mild renal injury (GFR less than 70 ml/min) was detected in two of seven evaluable children. This pilot study demonstrates the apparent efficacy and mild toxicity of 5 day courses of cisplatin plus VP-16, with delayed RT, in young children with CNS neoplasms. A POG treatment protocol that incorporates cisplatin plus VP-16 is evaluating primary chemotherapy with delayed radiotherapy in larger numbers of pediatric brain tumor patients.
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PMID:Efficacy of postoperative chemotherapy using cisplatin plus etoposide in young children with brain tumors. 199 Feb 53

Ribonucleic acid was isolated from a wide spectrum of central nervous system tumors to examine the expression of platelet-derived growth factors (PDGF) A and B, tumor growth factors (TGF-beta) 1 and 2, and ros messenger ribonucleic acid. Eight glioblastoma cell lines were examined as well as cell cultures from 22 tumor explants. The explants included 6 glioblastomas, 4 anaplastic astrocytomas, 5 astrocytomas, 3 ependymal tumors, 2 meningiomas, 1 medulloblastoma. and 1 ganglioglioma. For comparison, 2 nontumor glial cell cultures were included. The PDGF B-chain was expressed in 5 of 8 glioblastoma cell lines, 2 of 6 glioblastomas, and in 3 of 4 anaplastic astrocytoma explants. There was no PDGF B expression in 4 astrocytomas, 3 ependymomas of varying malignancy, in the remainder of the tumors, or in the nontumor glial cells. The PDGF A-chain was expressed in all of the tumors, with the exception of the malignant ependymoma and in both nontumor glial cell cultures. TGF-beta 1 was expressed in all of the tumors and in nontumor glial cells. The expression of TGF-beta 2 was expressed in many of the benign and malignant tumors and also in both nontumor glial cell cultures. The ros messenger ribonucleic acid was expressed in 1 of 5 glioblastoma cell lines and in 2 of 6 glioblastoma cell explants, but in none of the other tumors or in the nontumor glial cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression of platelet-derived growth factors, transforming growth factors, and the ros gene in a variety of primary human brain tumors. 199 89

This report describes a patient with an intramedullary ependymoma at the region of the cervicomedullary junction in whom there was an abolition of somatosensory evoked potentials following median nerve stimulation. During intraoperative monitoring of cortical potentials elicited by epidural cervical cord stimulation, the tumor was removed. Posterior epidural stimulation appeared to depolarize more ascending fibers than did stimulation of a single peripheral nerve. We recommend that, in cases of operations in this vital area, epidurally evoked cortical potentials be monitored intraoperatively.
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PMID:Usefulness of epidurally evoked cortical potential monitoring during cervicomedullary glioma surgery. 199 96


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