Tumor regrowth between surgery and initiation of adjuvant therapy in patients with newly diagnosed glioblastoma

To assess incidence and degree of regrowth in glioblastoma between surgery and radiation therapy (RT) and to correlate regrowth with presurgical imaging and survival, we examined images of 32 patients with newly diagnosed glioblastoma who underwent MR spectroscopic imaging (MRSI), perfusion-weighted imaging (PWI), and diffusion-weighted imaging (DWI) prior to surgery, after surgery, and prior to RT/temozolomide. Contrast enhancement (CE) in the pre-RT MR image was compared with postsurgical DWI to differentiate tumor growth from postsurgical infarct. MRSI and PWI parameters were analyzed prior to surgery and pre-RT. Postsurgical MRI indicated that 18 patients had gross total and 14 subtotal resections. Twenty-one patients showed reduced diffusion, and 25 patients showed new or increased CE. In eight patients (25%), the new CE was confined to areas of postsurgical reduced diffusion. In the other 17 patients (53%), new CE was found to be indicative of tumor growth or a combination of tumor growth and surgical injury. Higher perfusion and creatine within nonenhancing tumor in the presurgery MR were associated with subsequent tumor growth. High levels of choline and reduced diffusion in pre-RT CE suggested active metabolism and tumor cell proliferation. Median survival was 14.6 months in patients with interim tumor growth and 24 months in patients with no growth. Increased volume or new onset of CE between surgery and RT was attributed to tumor growth in 53% of patients and was associated with shorter survival. This suggests that reducing the time between surgery and adjuvant therapy may be important. The acquisition of metabolic and physiologic imaging data prior to adjuvant therapy may also be valuable in assessing regions of new CE and nonenhancing tumor.

Relationship of pre-surgery metabolic and physiological MR imaging parameters to survival for patients with untreated GBM

Glioblastoma Multiforme (GBM) are heterogeneous lesions, both in terms of their appearance on anatomic images and their response to therapy. The goal of this study was to evaluate the prognostic value of parameters derived from physiological and metabolic images of these lesions. Fifty-six patients with GBM were scanned immediately before surgical resection using conventional anatomical MR imaging and, where possible, perfusion-weighted imaging, diffusion-weighted imaging, and proton MR spectroscopic imaging. The median survival time was 517 days, with 15 patients censored. Absolute anatomic lesion volumes were not associated with survival but patients for whom the combined volume of contrast enhancement and necrosis was a large percentage of the T2 hyperintense lesion had relatively poor survival. Other volumetric parameters linked with less favorable survival were the volume of the region with elevated choline to N-acetylaspartate index (CNI) and the volume within the T2 lesion that had apparent diffusion coefficient (ADC) less than 1.5 times that in white matter. Intensity parameters associated with survival were the maximum and the sum of levels of lactate and of lipid within the CNI lesion, as well as the magnitude of the 10th percentile of the normalized ADC within the contrast-enhancing lesion. Patients whose imaging parameters indicating that lesions with a relatively large percentage with breakdown of the blood brain barrier or necrosis, large regions with abnormal metabolism or areas with restricted diffusion have relatively poor survival. These parameters may provide useful information for predicting outcome and for the stratification of patients into high or low risk groups for clinical trials.

Relationship between choline and apparent diffusion coefficient in patients with gliomas

PURPOSE

To examine the relationship between apparent diffusion coefficients (ADC) from diffusion weighted imaging (DWI) and choline levels from proton magnetic resonance spectroscopic imaging (MRSI) in newly diagnosed Grade II and IV gliomas within distinct anatomic regions.

MATERIALS AND METHODS

A total of 37 patients with Grade II and 28 patients with Grade IV glioma were scanned on a 1.5T system with 3D MRSI and DWI. Region level analysis included Spearman rank correlation between median normalized ADC and choline for each patient per grade within each distinct abnormal anatomical region. Voxel level analysis calculated a Spearman rank correlation per region, per patient.

RESULTS

Grade II lesions showed no evidence of a correlation between normalized ADC and choline using either the region or voxel level analysis. Region level analysis of Grade IV lesions did not appear to correlate in the contrast enhancement or necrotic core, but did suggest a significant negative correlation in the more heterogeneous nonenhancing and combined regions.

CONCLUSION

There appears to be differences in the relationship between ADC and choline levels in Grade II and Grade IV gliomas. Correlation within these regions in Grade IV lesions was strongest when all regions were included, suggesting heterogeneity may be driving the relationship.

Effect of maternal age, birth weight and infant sex on total nucleated cell (TNC) count and volume of umbilical cord blood (UCB) collected

This study evaluates the effect of maternal age, birth weight and infant sex on two main UCB parameters for use and long-term cryopreservation: TNC and volume. Data from 1000 UCB units were collected and analyzed in this study. The results indicate that TNC is correlated to infant birth weight and sex but not maternal age at delivery. Volume is only correlated to birth weight but not maternal age and infant sex.