Assessment of Progression-Free-Survival in Glioblastomas by Intratreatment Dynamic Contrast-Enhanced MRI.

Purpose: The efficacy of concomitant chemoradiation in patients with glioblastomas (GBMs) cannot be reliably assessed until several weeks after therapy completion. Our aim was to evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as an early predictive assay for the progression-free-survival.

Methods And Materials: A total of 22 patients with primary GBMs underwent DCE-MRI before, during and after completion of adjuvant chemoradiation. K (trans) (transfer constant between the intravascular and extravascular, extracellular space), v(e) (extracellular, extravascular volume) and IAUGC (initial area under the gadolinium concentration time curve) and their changes into treatment were assessed as prognostic markers (12 months of progression-free-survival (PFS)).

Results: Both responders (7 subjects) and non-responders (15 subjects) experienced a reduction in the baseline IAUGC and v(e) values during the early phase of the treatment. This reduction was more prominent in the responders and was statistically significant for the v(e) (P = 0.04). Baseline K (trans) values among responders demonstrated statistically significant reduction during the early phase of treatment (P = 0.001). Multivariate Cox regression analysis demonstrated significant relationship between response and the early changes in K (trans) values during the treatment (P = 0.04). Trend to significant prognostic value demonstrated the baseline K (trans), v(e) and IAUGC as well as the changes of IAUGC and K (trans) upon therapy completion.

Conclusions: Early perfusion changes during concomitant chemoradiation in GBMs can be detected by means of DCE-MRI and have significant prognostic value for the 12-month PFS.