Seizure outcomes of temporal lobe epilepsy surgery in patients with normal MRI and without specific histopathology.

BACKGROUND: Seizure outcome following surgery in pharmacoresistant temporal lobe epilepsy patients with normal magnetic resonance imaging and normal or non-specific histopathology is not sufficiently presented in the literature. METHODS: In a retrospective design, we reviewed data of 263 patients who had undergone temporal lobe epilepsy surgery and identified 26 (9.9%) who met the inclusion criteria. Seizure outcomes were determined at 2-year follow-up. Potential predictors of Engel class I (satisfactory outcome) were identified by logistic regression analyses. RESULTS: Engel class I outcome was achieved in 61.5% of patients, 50% being completely seizure free (Engel class IA outcome). The strongest predictors of satisfactory outcome were typical ictal seizure semiology (p = 0.048) and localised ictal discharges on scalp EEG (p = 0.036). CONCLUSION: Surgery might be an effective treatment choice for the majority of these patients, although outcomes are less favourable than in patients with magnetic resonance imaging-defined lesional temporal lobe epilepsy. Typical ictal seizure semiology and localised ictal discharges on scalp EEG were predictors of Engel class I outcome.

Genomic aberrations in pediatric gliomas and embryonal tumors.

The pathogenesis of pediatric central nervous system tumors is poorly understood. To increase knowledge about the genetic mechanisms underlying these tumors, we performed genome-wide screening of 17 pediatric gliomas and embryonal tumors combining G-band karyotyping and array comparative genomic hybridization (aCGH). G-banding revealed abnormal karyotypes in 56% of tumor samples (9 of 16; one failed in culture), whereas aCGH found copy number aberrations in all 13 tumors examined. Pilocytic astrocytomas (n = 3) showed normal karyotypes or nonrecurrent translocations by karyotyping but the well-established recurrent gain of 7q34 and 19p13.3 by aCGH. Our series included one anaplastic oligoastrocytoma, a tumor type not previously characterized genomically in children, and one anaplastic neuroepithelial tumor (probably an oligoastrocytoma); both showed loss of chromosome 14 by G-banding and structural aberrations of 6q and loss of 14q, 17p, and 22q by aCGH. Three of five supratentorial primitive neuroectodermal tumors showed aberrant karyotypes: two were near-diploid with mainly structural changes and one was near-triploid with several trisomies. aCGH confirmed these findings and revealed additional recurrent gains of 1q21-44 and losses of 3p21, 3q26, and 8p23. We describe cytogenetically for the first time a cribriform neuroepithelial tumor, a recently identified variant of atypical teratoid/rhabdoid tumor with a favorable prognosis, which showed loss of 1p33, 4q13.2, 10p12.31, 10q11.22, and 22q by aCGH. This study indicates the existence of distinct cytogenetic patterns in pediatric gliomas and embryonal tumors; however, further studies of these rare tumors using a multimodal approach are required before their true genomic aberration pattern can be finally established.

Multiple chromosomal monosomies are characteristic of giant cell ependymoma.

Giant cell ependymoma, a rare ependymoma subtype, was recently recognized as a separate diagnostic entity with variations both in malignant potential and course of disease. We analyzed the first supratentorial giant cell ependymoma using G-band karyotyping, DNA ploidy analysis, and array comparative genomic hybridization. The tumor was hypodiploid, and the karyotype showed multiple monosomies. This novel cytogenetic pattern seems specific for giant cell ependymoma as the only previous cytogenetic analysis of a giant cell ependymoma found similar monosomies. We were also able to analyze cytogenetically the subsequent recurrent tumor, phenotypically an anaplastic ependymoma, allowing a first insight into the genetic events involved in disease progression.

Microarray analysis reveals down-regulation of the tumour suppressor gene WWOX and up-regulation of the oncogene TYMS in intracranial sporadic meningiomas.

BACKGROUND: In order to investigate pathways that may influence on tumour development in meningiomas, we performed high throughput microarray analysis of the RNA expression and DNA copy number of 22 WHO grade I and five WHO grade II meningiomas. Since meningiomas derive from arachnoid cap cells, we used samples from four patients operated for arachnoid cysts as control tissue. RESULTS: The expression of the tumour suppressor gene WW containing oxidoreductase (WWOX) was down-regulated, and the thymidylate synthase (TYMS) oncogene was up-regulated in all meningiomas as compared to arachnoid cysts. Unsupervised RNA cluster analysis showed that fibrous meningiomas gathered in two clusters, and thus were more homogeneous than the other meningiomas. The other histological subgroups could not be linked to any uniform gene expression signatures. Rearrangements were most abundant on chromosomes 1 and 22, but were identified on all except chromosome 16. The fibrous and mixed meningiomas generally had chromosomal deletions. Duplications were more frequent in the meningothelial meningiomas. WHO grade II meningiomas had increased chromosomal instability. CONCLUSION: Decreased expression of the WWOX tumour suppressor gene and increased expression of the TYMS oncogene may be of importance for the development of human intracranial meningiomas. We have identified several genes (BMPR1B, DMD, RAMP1) with expression signatures specific for fibrous meningiomas. CGH analysis revealed distinct chromosomal patterns in relation to the histological subtypes of the meningiomas.

Increasing incidence and continued dismal outcome of primary central nervous system lymphoma in Norway 1989-2003 : time trends in a 15-year national survey.

BACKGROUND: The incidence of primary central nervous system lymphoma (PCNSL) appears to be increasing in some countries, whereas it is stable in others. Many reports the last decades have suggested that there have been improvements in the treatment of PCNSL. The objective of this study was to analyze time trends in the incidence, clinical features, histologic diagnosis, treatment, and outcome of nonacquired immunodeficiency syndrome (non-AIDS) PCNSL in Norway from 1989 to 2003. METHODS: Patients were identified by a chart review of all patients who had a recorded diagnosis of PCNSL from 1989 to 2003 in The Norwegian Cancer Registry. The histologic and cytologic material from each patient was re-examined by pathologists. Time trends were analyzed according to year of diagnosis grouped into 3 5-year periods: 1989-1993, 1994-1998, and 1999-2003. RESULTS: There were 98 patients who had confirmed, newly diagnosed non-AIDS PCNSL in Norway from 1989 to 2003. The incidence rate increased during the consecutive 5-year periods from 0.89 per million during 1989 to 1993, to 1.74 per million during 1994 to 1998, and to 1.82 per million during 1999 to 2003 (P = .013). Diagnostic delay and overall survival did not improve with time. Survival decreased from 1999 to 2003 compared with survival from 1994 to 1998, which was explained in part by reduced performance status and fewer patients receiving combined chemotherapy and radiotherapy during 1999 to 2003. In multivariate analysis, age

Severe fascioscapulohumeral muscular dystrophy presenting with Coats' disease and mental retardation.

We describe two Norwegian children with fascioscapulohumeral muscular dystrophy in whom Coats' disease, deafness, mental retardation and possible epilepsy were the presenting features. The children have a 4q35 deletion giving a small residual repeat fragment that they have inherited from their father who is a mosaic. Fundal changes consistent with bilateral Coats' disease were found in both children. The rapid development of neovascular glaucoma necessitated removal of an eye from one child that on pathological examination showed the classical features of Coats' disease. Cryotherapy was successful in maintaining sight in the other affected eyes.

Gamma-knife radiosurgery in pediatric cerebral and skull base tumors.

BACKGROUND: This retrospective study of 12 children with cerebral or skull base tumors was undertaken to evaluate morbidity and outcome after gamma-knife surgery. PROCEDURE: Twelve consecutive children treated with stereotactic radiosurgery in a curative intent were reviewed. There were five girls and seven boys. The mean age at diagnosis was 5.8 years and at radiosurgical treatment 8.4 years. There were four pilocytic astrocytomas, two craniopharyngeomas, two pineoblastomas, two ependymomas, and two other tumors of high malignancy. We used a 201-source Co60 Leksell gamma knife and all children were treated in general anesthesia. RESULTS: The mean tumor volume was 3.7 cm(3) and the mean tumor margin dose was 13.8 Gy. Seven patients remained stable after gamma-knife treatment with a mean follow- up of 78.6 months. One patient died during follow-up. The remaining four patients had progressive disease, two within and two outside the irradiated field, and have received further treatment. They are still alive with and without disease with a mean follow-up of 96.8 months. CONCLUSION: Gamma-knife surgery is an effective treatment in some non-resectable cerebral and skull base pediatric tumors. In most cases, it is used in combination with other therapeutic modalities. It is safe and well tolerated.