Oligodendrogliomas comprise approximately 4% of the total of brain tumours, and of this group only 7% are found in the posterior fossa, including 2% in the fourth ventricle. Oligodendrogliomas of the fourth ventricle therefore comprise less than one case in 1,000 to 1,500 brain tumours (0 08 %). One cannot expect to encounter much more than one in a lifetime even in a large-neurosurgical experi...

Very little is known of the genes and mechanisms contributing to the genesis of oligodendrogliomas, a subtype of primary brain tumors. Using an integrated genetic and epigenetic analysis of oligodendrogliomas, we show that aberrant CpG island methylation is the most prevalent alteration in these tumors, and the majority of methylated genes are independent of regions affected by deletion. In con...

Very little is known of the genes and mechanisms contributing to the genesis of oligodendrogliomas, a subtype of primary brain tumors. Using an integrated genetic and epigenetic analysis of oligodendrogliomas, we show that aberrant CpG island methylation is the most prevalent alteration in these tumors, and the majority of methylated genes are independent of regions affected by deletion. In con...

PURPOSE AND EXPERIMENTAL DESIGN In modern neuro-oncology, no variable affects therapeutic decisions and prognostic estimation more than tumor classification. We showed recently that class prediction models, based on gene expression profiles, classify diagnostically challenging malignant gliomas in a manner that better correlates with clinical outcome than standard pathology. In the present stud...

BACKGROUND: Recent reports indicate that anaplastic oligodendrogliomas frequently show allelic losses on chromosome arms 1p and 19q, and that these deletions are associated with better chemotherapeutic response and overall patient survival. Because of the diversified genetic makeup of the population and the centralized provincial referral system for brain tumor patients in Manitoba, the epidemi...

Introduction: Treatment of patients with oligodendrogliomas depends on their histopathological grade and cytogenetic profile. Oligodendrogliomas with 1p and 19q loss of heterozygosity (LOH) are known to be more sensitive to the chemotherapy. In the present study, we evaluated the utility of perfusion weighted imaging (PWI) and multivoxel proton magnetic resonance spectroscopy (H MRS) in differe...

In this issue of Clinical Cancer Research, Walker et al. (1) report a comprehensive analysis of metabolic rate, tumor grade, contrast enhancement, and molecular genetic alterations in oligodendrogliomas and oligoastrocytomas. Brain tumor metabolism was assessed by single-photon emission computed tomography (SPECT) using two radiolabeled tracers, thallium (Tl) and [F]fluorodeoxyglucose (FDG). Tl...

BACKGROUND AND PURPOSE The purpose of this study was to derive quantitative parameters from magnetic resonance (MR) spectroscopic, perfusion, and diffusion imaging of grade 2 gliomas according to the World Health Organization and to investigate how these multiple imaging modalities can contribute to evaluating their histologic subtypes and spatial characteristics. MATERIALS AND METHODS MR spe...

Cyclooxygenases (COX, prostaglandin endoperoxide synthases, PGG/H synthases) are potent mediators of edema, impeding blood flow and immunomodulation in the pathologically altered brain. Two COX iso-enzymes have been associated with brain disease, the constitutively expressed COX-1 and the cytokine-inducible COX-2. We have used single and double labeling immunohistochemistry to analyse COX-1 and...