PT  - JOURNAL ARTICLE
AU  - Pope, W.B.
AU  - Lai, A.
AU  - Mehta, R.
AU  - Kim, H.J.
AU  - Qiao, J.
AU  - Young, J.R.
AU  - Xue, X.
AU  - Goldin, J.
AU  - Brown, M.S.
AU  - Nghiemphu, P.L.
AU  - Tran, A.
AU  - Cloughesy, T.F.
TI  - Apparent Diffusion Coefficient Histogram Analysis Stratifies Progression-Free Survival in Newly Diagnosed Bevacizumab-Treated Glioblastoma
AID  - 10.3174/ajnr.A2385
DP  - 2011 May 01
TA  - American Journal of Neuroradiology
PG  - 882--889
VI  - 32
IP  - 5
4099  - http://www.ajnr.org/content/32/5/882.short
4100  - http://www.ajnr.org/content/32/5/882.full
SO  - Am. J. Neuroradiol.2011 May 01; 32
AB  - BACKGROUND AND PURPOSE: Currently it is difficult to predict tumor response to anti-angiogenic therapy in individual patients. Our aim was to determine if ADC histogram analysis can stratify progression-free and overall survival in patients with newly diagnosed GBM treated “up-front” (ie, before tumor recurrence) with bevacizumab. MATERIALS AND METHODS: Up-front bevacizumab-treated and control patients (n = 59 and 62, respectively) with newly diagnosed GBM were analyzed by using an ADC histogram approach based on enhancing tumor. Progression-free and overall survival was determined by using Cox proportional HRs and the Kaplan-Meier method with logrank and Wilcoxon tests. RESULTS: For up-front bevacizumab-treated patients, lower ADCL was associated with significantly longer progression-free survival (median, 459 days for ADCL < 1200 versus 315 days for ADCL ≥ 1200 10−6mm2/s; P = .008, logrank test) and trended with longer overall survival (581 versus 429 days, P = .055). ADC values did not stratify progression-free or overall survival for patients in the control group (P = .92 and P = .22, respectively). Tumors with MGMT promoter methylation had lower ADCL values than unmethylated tumors (mean, 1071 versus 1183 10−6mm2/s; P = .01, 2-group t test). CONCLUSIONS: Pretreatment ADC histogram analysis can stratify progression-free survival in bevacizumab-treated patients with newly diagnosed GBM. Lower ADC is associated with tumor MGMT promoter methylation, which may, in part, account for the favorable outcome associated with low ADCL tumors. ADCapparent diffusion coefficientADCLmean ADC (10−6mm2/s) of the lower curve from the histogram analysisFLAIRfluid-attenuated inversion recoveryGgross total resectionGBMglioblastomaHRhazard ratioKPSKarnofsky Performance StatusMmethylatedMGMTO6-methylguanine-DNA-methyltransferaseNno tissue availableRPArecursive partitioning analysisSsubtotal resection and biopsyUunmethylatedVEGFvascular endothelial growth factor