The addition of six cycles of PCV after 59.4 Gy of RT increases both OS and PFS in anaplastic oligodendroglial tumors. 1p/19q-codeleted tumors derive more benefit from adjuvant PCV compared with non-1p/19q-deleted tumors.

Adjuvant PCV chemotherapy does not prolong OS but does increase PFS in anaplastic oligodendroglioma. Combined loss of 1p/19q identifies a favorable subgroup of oligodendroglial tumors. No genetic subgroup could be identified that benefited with respect to OS from adjuvant PCV.

A semiautomatic method based on a computerized digital image analysis system was developed to quantitate the perfused fraction of blood vessels and the relative vascular area in cross-sections of human glioma xenografts, implanted subcutaneously in athymic mice or intracerebrally in nude rats. The fluorescent dye Hoechst 33342 was injected intravenously to detect perfused tumor vessels. An immunofluorescent staining of Collagen type IV visualized the vascular structures in the same tumor section. Whole tumor sections were automatically scanned twice on a computercontrolled motorized stage of a fluorescence microscope under two different settings of the image analysis system. At the beginning of a scanning session an interactive routine was used to determine the threshold value for segmentation of vascular structures from the darker background. After the first scan a composite image was created, from the individually processed microscopic images, containing the detected vascular structures. The second scan yielded another composite image with objects representing the perfused areas. When both composite images were combined the overlapping structures showed the perfused vessels. Differences in perfused fractions and relative vascular areas were found between different tumors. The reproducibility of this analysis system was tested and evaluated. The method developed here provides a fast and accurate technique for simultaneous quantitative analysis of tumor perfusion and vasculature.

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Oligodendroglial tumors may not be distinguished easily from other brain tumors based on clinical presentation and magnetic resonance imaging (MRI) alone. Identification of these tumors however may have therapeutic consequences. The purpose of this study was to characterize and identify oligodendrogliomas by their metabolic profile as measured by 1 H MR spectroscopic imaging (MRSI). Fifteen patients with oligodendroglial tumors (eight high-grade oligodendrogliomas, seven low-grade oligodendrogliomas) underwent MRI and short echo time 1 H MRSI examinations. Five main metabolites found in brain MR spectra were quantified and expressed as ratios of tumor to contralateral white matter tissue. The level of lipids plus lactate was also assessed in the tumor. For comparison six patients with a low grade astrocytoma were also included in the study. The metabolic profile of oligodendrogliomas showed a decreased level of N-acetylaspartate and increased levels of choline-containing compounds and glutamine plus glutamate compared with white matter. The level of glutamine plus glutamate was significantly higher in low-grade oligodendrogliomas than in low-grade astrocytomas and may serve as a metabolic marker in diagnosis and treatment planning. In high-grade oligodendrogliomas large resonances of lipids plus lactate were observed in contrast to low-grade tumors.