Apparent diffusion coefficient for molecular subtyping of non-gadolinium-enhancing WHO grade II/III glioma: volumetric segmentation versus two-dimensional region of interest analysis

Eur Radiol. 2018 Sep;28(9):3779-3788. doi: 10.1007/s00330-018-5351-0. Epub 2018 Mar 23.


Objectives: To investigate if quantitative apparent diffusion coefficient (ADC) measurements can predict genetic subtypes of non-gadolinium-enhancing gliomas, comparing whole tumour against single slice analysis.

Methods: Volumetric T2-derived masks of 44 gliomas were co-registered to ADC maps with ADC mean (ADCmean) calculated. For the slice analysis, two observers placed regions of interest in the largest tumour cross-section. The ratio (ADCratio) between ADCmean in the tumour and normal appearing white matter was calculated for both methods.

Results: Isocitrate dehydrogenase (IDH) wild-type gliomas showed the lowest ADC values throughout (p < 0.001). ADCmean in the IDH-mutant 1p19q intact group was significantly higher than in the IDH-mutant 1p19q co-deleted group (p < 0.01). A volumetric ADCmean threshold of 1201 × 10-6 mm2/s identified IDH wild-type with a sensitivity of 83% and a specificity of 86%; a volumetric ADCratio cut-off value of 1.65 provided a sensitivity of 80% and a specificity of 92% (area under the curve (AUC) 0.9-0.94). A slice ADCratio threshold for observer 1 (observer 2) of 1.76 (1.83) provided a sensitivity of 80% (86%), specificity of 91% (100%) and AUC of 0.95 (0.96). The intraclass correlation coefficient was excellent (0.98).

Conclusions: ADC measurements can support the distinction of glioma subtypes. Volumetric and two-dimensional measurements yielded similar results in this study.

Key points: • Diffusion-weighted MRI aids the identification of non-gadolinium-enhancing malignant gliomas • ADC measurements may permit non-gadolinium-enhancing glioma molecular subtyping • IDH wild-type gliomas have lower ADC values than IDH-mutant tumours • Single cross-section and volumetric ADC measurements yielded comparable results in this study.

Keywords: Brain; Diffusion magnetic resonance imaging; Glioma; Isocitrate dehydrogenase; Neuroimaging.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Brain / diagnostic imaging
  • Brain / pathology
  • Brain Neoplasms / diagnostic imaging*
  • Brain Neoplasms / pathology*
  • Contrast Media*
  • Diffusion Magnetic Resonance Imaging / methods
  • Female
  • Gadolinium*
  • Glioma / diagnostic imaging*
  • Glioma / pathology*
  • Humans
  • Image Enhancement
  • Isocitrate Dehydrogenase
  • Male
  • Middle Aged
  • Neoplasm Grading
  • Retrospective Studies
  • Sensitivity and Specificity
  • World Health Organization


  • Contrast Media
  • Gadolinium
  • Isocitrate Dehydrogenase