Table 3 Applications in selecting optimal therapy.

From: Radiomics and radiogenomics in gliomas: a contemporary update

Author

No. of patients

Magnet strength/MRI sequence

Segmentation manual vs automatic

Texture software

Type of radiomic analysis

Best discriminating features

Machine learning/statistical approach

Results

Beig et al.137

83 LGGs

T2w/FLAIR

Manual 2D

Matlab

GLCM, Gabor

3D Gabor

SVM

Initial results indicate that radiomic features from non-enhancing regions on T2 and infiltrative edges on FLAIR can segregate the 3 subgroups.

Zhang et al.63

152 (IDH mutant = 92, wild-type = 60)

1.5T–3 T/T1-CE, T2WI, FLAIR

Manual 3D

Matlab

GLCM GLGCM

15 Optimal features from 168 Haralick features

SVM-RFE

AUC 0.841 and accuracy of 82.2% for non-invasively discriminating IDH mutation of patient with glioma

Hsieh et al.138

39 (IDH mutant = 7, wild-type = 32; TCGA)

1.5T–3 T/T1-CE

Manual 2D

CAD system

Morphological intensity-GLCM

14 GLCM

Binary logistic regression classifier

Textural features describing local patterns yielded an accuracy of 85% in detecting the IDH status

Han et al.64

42 (IDH mutant = 21, wild-type = 21)

3 T/T1WI, T2WI, 3D-T1-CE

Manual 3D

OmniKinetics

29 Texture features from first-order and GLCM

Inertia, cluster prominence, GLCM entropy

–

Showed joint variables derived from T1WI, T2WI, and contrast-enhanced T1WI imaging histograms and GLCM features could be used to detect IDH1-mutated gliomas. The AUC of Joint VariableT1WI+C for predicting IDH1 mutation was 0.984, and the AUC of Joint VariableT1WI for predicting the IDH1 mutation was 0.927

Jakola et al.65

25 (IDH mutant = 20, wild-type = 5)

3 T/3D-FLAIR

Semiautomatic 3D

ImageJ

Homogeneity, energy, entropy, correlation, inertia

Homogeneity

–

Homogeneity discriminated patients with LGG in IDH mutant and IDH wild-type (P = 0.005), AUC for combined parameters was 0.940 for predicting IDH mutation; authors could not separate IDH-mutant tumours on basis of 1p/19q-codeletion status

Bahrami et al.66

61 (IDH mutant = 43, wild-type = 11); 7 unknown)

3 T/Pre- and post-T1-CE, FLAIR

Semiautomatic 3D

3D-co-occurrence matrix

Histogram, GLCM

Homogeneity, pixel correlation, EC

Logistic regression with LASSO regularization

Greater signal heterogeneity and lower EC noted in IDH wild-type tumours; IDH mutant tumours with 1p/19q-codeleted status; lower EC in MGMT-methylated tumours

Shofty et al.139

47 LGGs

1.5T–3 T/FLAIR, T2, TI-CE

Automatic using FSLa, 3D

Matlab

Histogram, contrast, correlation, energy, entropy, homogeneity

39 of 152 textural features

17 classifiers

Ensemble of bagged trees classifier achieved the best performance (Accuracy = 87%; AUC = 0.87) for the detection of 1p/19q codeletion; majority of differences detected for T2 and T1-CE

Kickingereder et al.94

172 (GBM)

3 T/Pre- and post-T1-CE, FLAIR

Semiautomatic 3D

Medical imaging Toolkitb

188 imaging features, 17 first-order features (FO), 9 volume and shape features (VSF) and 162 texture features (GLCM,) GLRLM).

–

Supervised principal component (superpc) analysis

The superpc predictor stratified patients in the validated set into a low or high-risk group for PFS (HR = 1.85, P = 0.030) and OS (HR = 2.60, P = 0.001).

Grossmann et al.100

126 (GBM)

Baseline and follow-up

MRI (1 and 6 wks), T1WI, T2WI, FLAIR, T1-CE

Semi-automatically with

Slicer 3Dd

R version 3.1.0c

First-order statistics of the voxel

intensity histogram; tumour shape; tumour texture

Information correlation

PCA

Radiomics provides prognostic value for survival and progression in patients with recurrent glioblastoma receiving bevacizumab treatment; features derived from postcontrast T1WI yielded higher prognostic power compared with T2WI

Wu et al.140

126 (grade II-III = 43 and grade IV = 83)/TCIA

T1, T1-CE, T2, FLAIR

Semiautomatic approach

R version 3.3.1c

GLCM texture, Volume, intensity, histogram, diffusion

20 of 704 radiomic features

SVM, kNN, RF, NB, NN, FDA, Adaboost/tenfold cross-validation

Random Forest (RF) showed high predictive performance for identifying IDH genotype (AUC = 0.931, accuracy=88.5%)

Zhou et al.141

744 (LGG, HGG)/ TCIA, local datasets

T1-CE, T2-FLAIR

Semi-automatically with Slicer 3Dd

Matlab

Histogram, texture, age, shape

Top 15 features out of 127

RF/Train-test model

The overall accuracy for 3 group prediction (IDH-wild type, IDH-mutant and 1p19q co-deletion, IDH-mutant and 1p19q non-codeletion) was 78.2%

Lee et al.142

123 (GBM)

T1, T2, T1-CE, FLAIR, PWI, DWI

Manual segmentation

Nordi-cICE

Volume, ADC map, CBV

Four of 31 radiological features

kNN, SVM, RF, Adaboost, decision tree, NB, LDA, gradient boosting

Prediction rate of IDH1 mutation status with 66.3–83.4% accuracy

Sudre et al.143

333 (IDH mutant = 151, wild-type = 182);

1.5 T/T1, T2, FLAIR, DSC MRI

Olea Sphere, Version 3

–

Shape, intensity, texture

Nine histogram features, 11 texture features

RF/cross-validation

Gliomas were correctly stratified 53% for grade classification and 71% for IDH classification

  1. GLCM grey level co-occurrence matrix, GLRLM grey level run-length matrix features, LDA linear discriminant analysis, PCA principal component analysis, Adaboost adaptive boosting, NB Naive Bayes, FDA flexible discriminant analysis, NN neural network.
  2. aFSL (http://www.fmrib.ox.ac.uk/fsl).
  3. bhttp://www.mitk.org/wiki/The_Medical_Imaging_Interaction_Toolkit_(MITK).
  4. cR statistical and computing software (http://www.r-project.org).
  5. dhttp://www.slicer.org.