Table 2 Prognostic applications.

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.87

115 (GBM)

T1WI, T2WI, FLAIR

Manual 2D

Matlab

30 features: Laws, Gabor, GLCM

Laws energy (R5R5, E5E5, S5S5) from enhancing tumour and oedema

RF model

Features from the enhancing and oedematous regions were predictive of the extent of hypoxia. Features on the validation set were also found to be prognostic of overall survival

Kickingereder et al.88

119 (GBM)

3 T/T1-CE, FLAIR

Manual 3D

Medical Imaging Toolkita

Histogram volume

and shape

features; texture

features; wavelet

analysis

11 features of 12,190 features

SPC analysis

SPC analysis performed better than clinical (age and Karnofsky Performance Score) and radiologic (rCBV and ADC) parameters

Molina et al.128

79 (GBM)

1.5–3 T/T1-CE

Manual 3D

Matlab

Five GLCM features, 11 GLRLM features

GLCM (entropy, homogeneity,

contrast, dissimilarity) GLRLM

(LRE, HGLRE, LRHGE, RPC)

Kaplan–Meier curves and Cox-proportional hazards analysis

Patients had better prognosis when high LRHGE, low RPC, low entropy, high homogeneity, and low dissimilarity were present (P < 0.05)

Chaddad et al.129

73 (GBM)/ TCIA

T1-CE, FLAIR

Semi-automatic 2D

–

GLCM JIM

JIM (entropy, inverse-variance)

in necrosis region and (entropy,

contrast) in oedema region

RF model

JIM of T1-CE and FLAIR images significantly predicted survival outcomes with moderate correlation; nine features were found to be associated with glioblastoma survival, P < 0.05, accuracy of 68%-70%; AUC of 77.56% with P = 0.003 was achieved when combining JIM, GLCM, and gene expression features into a single radiogenomic signature.

Liu et al.130

119 (GBM)/TCGA

T1WI, T2WI, FLAIR,

T1-CE

Manual 2D

–

Histogram, GLCM, GLRLM

13 textural features

SVM-RFE

T1-CE sequence performed best, with AUC of 0.7915 and accuracy of 80.67%

Yang et al.131

82 (GBM)/TCGA

T1-CE, T2WI, FLAIR

Manual 3D

Matlab

SFTA, RLM, LBP, HOG, Haralick texture features

–

RF model

Molecular subtypes and 12-month survival was predicted by several features; SFTA features on T1-CE were most predictive of survival and proneural subtype (AUC = 0.82); RLM features on T2 FLAIR axial for neural (AUC = 0.75); Haralick features on T1-CE for classic (AUC = 0.72); HOG features on T2 FLAIR axial for mesenchymal (AUC = 0.70)

Bahrami et al.95

33 (HGG)

3 T/FLAIR

Semi-automatic 3D

–

EC

–

Kaplan–Meier curves

Reported that lower EC of the FLAIR hyperintense region was associated with poor PFS (P = 0.009) and OS (P = 0.022) status post-bevacizumab therapy

Jain et al.89

45 (GBM)

1.5/3 T, T1, T2w/perfusion, FLAIR

Manual 2D

Rb

VASARI features, rCBV statistics

rCBVNER

Random Survival Forest

Increased maximum rCBVCER found to be associated with increased risk of death

McGarry et al.90

81 (GBM)

1.5/3 T, T1, CE-T1, T2, FLAIR

Semi-automatic 3D

–

81 radiomic profiles (5 RPs): 4-digit code assigned to each voxel representing the intensity-based segmentation

Five RPs correlated with survival when thresholded by volume

Cox Regression

Presented a method for creating radiographic profiles by combining intensity information from multiple MRI scans. Pathologically validated that voxels indicated by one of the RPs contained hypercellular tumour and necrosis.

Lao et al.117

112 (GBM)

1.5/3 T, T1, T1-CE, T2, FLAIR

Manual 2D

Python CAFFE

1403 handcrafted (HC) features: geometry, intensity, texture and 98304 deep features using transfer learning

150 HC and deep features

LASSO Cox Regression

The radiomics signature achieved a C-Index of 0.731 for the discovery dataset, and 0.710 for the independent validation set.

Li et al.132

92 (GBM)/TCIA, local data

T1, T1-CE, T2, FLAIR

Automated using Matlab

Rb

Texture at different voxel size, quantization and grey levels

-

Cox regression model

The multiparametric signature achieved better performance for OS prediction (C-Index = 0.705)

Sun et al.133

542 (training n = 285; validation =66; test=191; LGG,HGG)/BRATS 2018

T1, T1-CE, T2, FLAIR

3D CNN architectures

Pyradiomics toolbox

Shape, texture, first-order statistics

Age, 14 selected features

RF regression

Achieved 61% accuracy in predicting survival outcome.

Sanghani et al.134

163 (GBM)/BRATS 2017

T1, T1-CE, T2, FLAIR

Segmentation masks from BraTS 2017 dataset

–

Texture, shape, volumetric, age

Top 150 selected features out of 2200

SVM-RFE/fivefold cross-validation

The 2-class and 3-class OS group prediction accuracy obtained were 98.7% and 88.95% respectively.

Beig et al.135

460 (GBM), Male = 290, female = 170

T1, T1-CE, T2, FLAIR

Semi-automatically with Slicer 3Dd

Matlab

2850 features: Laws, Gabor, shape based

Five Laws energy, two Gabor wavelets; one shape based

Cox regression model

Sexually dimorphic radiomic risk score (RRS) models that are prognostic of overall survival (OS) in primary GBM

Han et al.136

178 (HGG)/TCIA, local dataset

T1-CE

Manual segmentation

Matlab, Kerasc, R

348 handcrafted - volume, size, texture, intensity, first-order statistical + 8192 deep CNN features

–

Elastic net-Cox modelling

The combined feature analysis framework classified the patients into long- and short-term survivor groups with a log-rank test P < 0.001

  1. EC Edge contrast, JIM joint intensity matrices, RF random forest, TCGA The Cancer Genome Atlas, TCIA The Cancer Imaging Archive, LRE long-run emphasis, HGLRE high grey-level run emphasis, LRHGE long-run high grey-level emphasis, RPC run percentage, SFTA segmentation-based fractal texture analysis, LBP local binary pattern, HOG histogram-oriented gradient, SPC supervised principal component.
  2. ahttp://www.mitk.org/wiki/The_Medical_Imaging_Interaction_Toolkit_(MITK).
  3. bR statistical and computing software (http://www.r-project.org).
  4. cKeras (www.keras.io).
  5. dhttp://www.slicer.org.