Thanh Nguyen MD, Presenter: Research grant, Bayer AG

Gregory O. Cron, Abstract Co-Author: Nothing to Disclose

Jean-Francois Mercier MD, Abstract Co-Author: Nothing to Disclose

Claire Foottit PhD, Abstract Co-Author: Nothing to Disclose

Rebecca Thornhill, Abstract Co-Author: Nothing to Disclose

Mark E. Schweitzer MD, Abstract Co-Author: Consultant, Paradigm Spine LLC Consultant, Pfizer Inc

John Woulfe, Abstract Co-Author: Nothing to Disclose

Carlos Hernando Torres MD, Abstract Co-Author: Nothing to Disclose

Santanu Chakraborty, Abstract Co-Author: Nothing to Disclose

John Sinclair, Abstract Co-Author: Nothing to Disclose

Ian Cameron, Abstract Co-Author: Nothing to Disclose

Jean-Michel Caudrelier MD, Abstract Co-Author: Nothing to Disclose

Dynamic contrast-enhanced (DCE) MR imaging has shown potential for predicting the biologic aggressiveness of cerebral gliomas. The perfusion parameter cerebral blood volume (CBV) has been found to provide particularly valuable prognostic information in numerous studies. On the other hand, there have been only a few studies on the parameter Ktrans (volume transfer constant). Hence, the purpose of this study was to determine the relationship between survival time and Ktrans in patients with gliomas.

At 1.5 T, 31 patients with a new diagnosis of biopsy proven cerebral glioma (7 grade II, 4 grade III, 20 grade IV) were prospectively studied. DCE MRI was performed with 2D FLASH (TR/TE/flip 50ms/2.1 & 5.5 ms/90 deg). Temporal resolution was 2.2s for a duration of 180 seconds. Gadopentetate dimeglumine was injected at 0.1 mmol/kg at 4cc/s. Bookend T1 measurements and MR signal phase were used to obtain Gd concentration-vs-time in the vessels and tissue. Tracer kinetic modeling was used to obtain parametric maps of Ktrans and CBV, using regions of interest (ROIs) drawn over the superior sagittal sinus on phase maps to obtain the arterial input function. 4 circular ROIs were drawn on each tumor. Maximal ROI value for Ktrans was obtained for each patient. Values of Ktrans were used to divide patients into 4 arbitrary quartile groups. Survival curves were estimated by the Kaplan-Meier method. A logrank test was used to determine if there was a statistically significant difference in survival between groups.

There was a trend of increasing Ktrans with increasing tumor grade. The mean Ktrans values were 0.019±0.013 min-1 for grade II, 0.060±0.071 min-1 for grade III and 0.095±0.047 min-1 for grade IV. For all patients with gliomas, there was a significant difference in survival among the 4 quartile groups for Ktrans irrespective of grade (χ2=10.8, p=0.01). The follow-up period ranged between 8 and 27 months. The hazard ratio between the lowest quartile group (Ktrans 0–0.05 min-1) and the highest quartile group (Ktrans 0.15-0.20 min-1) was 7.4 (95% confidence interval 0.63-88.2).

This study suggests that Ktrans in gliomas is inversely related with length of survival.

We may be able to use Ktrans to prognosticate patients with cerebral gliomas.

Nguyen, T, Cron, G, Mercier, J, Foottit, C, Thornhill, R, Schweitzer, M, Woulfe, J, Torres, C, Chakraborty, S, Sinclair, J, Cameron, I, Caudrelier, J, Evaluation of MR-derived Ktrans as a Prognostic Marker in Patients with Gliomas.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11013275.html