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) (B&L-ADC) 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 were analyzed. We dichotomized the lower mean of ADC (L-ADC) and the broader width of ADC (B-ADC) at their own average. B&L-ADC was defined as B-ADC with L-ADC. 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 values. B&L-ADC 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. There was no significant difference in the OS-PFS duration difference between the patients with (median, 79 days) and without B&L-ADC (median, 132 days) (P=0.348).

CONCLUSION

In this study, B&L-ADC from pretreatment ADC analysis predicted poor PFS. B&L-ADC may indicate higher cellularity and heterogeneity in GBM tumor tissue.