Apparent diffusion coefficient histogram analysis for prediction of prognosis in glioblastoma

Background. - To investigate the potential to predict prognosis of glioblastoma (GBM) patients by analysis of the broader and lower values in the lower distribution of apparent diffusion coefficient (ADC(L)) (B&L-ADC(L)) values in the ADC histogram. Background. - Presurgical publicly available diffusion-weighted images (DWI) and contrast-enhanced T1-weighted images from 76 GBM patients were analyzed. With applied 2-mixture normal distribution in the ADC histogram of enhanced lesions on T1-weighted images, the mean and width of ADC(L) were analyzed. We dichotomized the lower mean of ADC(L) (L-ADC(L)) and the broader width of ADC L (B-ADC(L)) at their own average. B&L-ADC(L) was defined as B-ADC(L) with L-ADC(L). Progression-free survival (PFS) and overall survival (OS) were determined by using Cox proportional hazards analysis and the Kaplan-Meier method with the log-rank test. The difference between PFS and OS was calculated. Results. - Six (7.89%) patients had B&L-ADC(L) values. B&L-ADC(L) was strongly associated with poor PFS (hazard risk: 5.747; P = 0.002) and OS (hazard risk: 3.331; P = 0.018). There were significant differences in PFS (median, 77 vs. 302 days; P < 0.001) and OS (median, 199 vs. 472 days; P = 0.004) between the patents with and without B&L-ADC(L). There was no significant difference in the OS-PFS duration difference between the patients with (median, 79 days) and without B&L-ADC(L) (median, 132 days) (P = 0.348). Conclusion. - In this study, B&L-ADC(L) from pretreatment ADC analysis predicted poor PFS. B&L-ADC(L) may indicate higher cellularity and heterogeneity in GBM tumor tissue. (C) 2017 Elsevier Masson SAS. All rights reserved.