Romina Zalazar MD, Presenter: Nothing to Disclose

Miguel David Hernandez Arguello MD, Abstract Co-Author: Nothing to Disclose

Maria Paramo Alfaro MD, Abstract Co-Author: Nothing to Disclose

Pablo Daniel Dominguez MD, Abstract Co-Author: Nothing to Disclose

Jose Luis Zubieta, Abstract Co-Author: Nothing to Disclose

Jose luis solorzano, Abstract Co-Author: Nothing to Disclose

Paula Barquin Garcia MD, Abstract Co-Author: Nothing to Disclose

Maria De Los Reyes Garcia de Eulate, Abstract Co-Author: Nothing to Disclose

To analyse whether apparent diffusion coefficient (ADC) values correlate with survival and with methylguanine-DNA-methyltransferase (MGMT) promoter methylation status and epidermal growth factor receptor (EGFR) amplification on glioblastoma multiforme (GBM).

72 patients with untreated GBM before surgery were analysed (mean time MRI-Surgery=6 days). Patients were followed-up for at least 12 months or until death. A ROI were drawn on ADC-map in the highest restriction region of the tumor and on the normal-appearing contralateral white matter (NCWM). ADCmin-values and ADC-index defined as a ratio between tumoral ADCmin and NCWM-ADCmean were evaluated. MGMT-status(n=60), EGFR amplification(n=53), KPS, tumoral and residual volume, progression-free survival (PFS) and overall survival (OS) were analysed. Kaplan-Meier and Cox-regression model were performed.

53 patients had complete resection. Presurgical and post-surgical mean tumoral volume were 42.4cm3 and 0.57cm3 respectively. Non methylated-MGMT-status(n=27) and low ADC values (<0.7) correlates with a decrease in PFS and OS (p<0.001). EGFR amplification (n=19) was correlated with a decrease in PFS (p=0.029) only when low ADC values and non--methylated-MGMT-status were present. EGFR amplification was not correlated with a poor outcome in the group of higher ADC values and MGMT methylated status (p<0.001). On Kaplan-Meier analyses MGMT-status correlated better with PFS (p=0.002), while ADC values correlate better with OS (p 0.001). In the multivariate analysis low ADC values and MGMTNM status were significant predictors of prognosis when they were adjusted by clinical variables (p= 0.001 and p=0.037, respectively).

The combined use of ADC values and MGMT-status are stronger predictors than using separated in GBM and could modulate outcome in patients with EFGR amplification.

ADC values in GBM correlates significantly with survival, independently of the MGMT and EGFR status .Therefore, ADC values could be used as independent predictors of survival in those patients.

Zalazar, R, Hernandez Arguello, M, Paramo Alfaro, M, Dominguez, P, Zubieta, J, solorzano, J, Garcia, P, Garcia de Eulate, M, Prognostic Value of ADC and Its Correlation with Methylguanine-DNA- Methyltransferase (MGMT) Promotor Methylation Status and Epidermal Growth Factor Receptor (EGFR) Amplification and Survival in Glioblastoma Multiforme (GBM).  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14018605.html