Table 6.
Features selected by the GBDT in the two groups.
| Group 1: AMCs to thymomas | Group 2: Low-risk to high-risk thymomas | ||
|---|---|---|---|
| NECT-based RM; | NECT-based CM; | NECT-based RM; | NECT-based CM; |
| N=8 | N=11 | N=15 | N=12 |
| CONVENTIONAL_HU min | CONVENTIONAL_HUQ2 | CONVENTIONAL_HU min | CONVENTIONAL_HUQ2 |
| CONVENTIONAL_HU max | SHAPE_Sphericity onlyFor3DROI) | CONVENTIONAL_HUQ2 | SHAPE_Sphericity only For 3D ROI) |
| CONVENTIONAL_HUQ2 | GLCM_Correlation | DISCRETIZED_HUQ2 | SHAPE_Surface (mm2) only For 3D ROI |
| CONVENTIONAL_HUQ3 | GLRLM_LGRE | SHAPE_Sphericity only For 3D ROI) | SHAPE_Compacity onlyFor3DROI |
| SHAPE_Sphericity only For 3D ROI) | CONVENTIONAL_HUmin | SHAPE_Surface(mm2) only For 3D ROI | GLCM_Correlation |
| SHAPE_Surface (mm2) only For 3D ROI | Symptoms | SHAPE_Compacity only For 3D ROI | GLRLM_SRLGE |
| GLCM_Correlation | Average CT value | GLCM_Energy =Angular Second Moment | GLZLM_HGZE |
| GLZLM_LZLGE | Maximum diameter on axial image(cm) | GLCM_Correlation | GLZLM_GLNU |
| Ratio of max diameter to min diameter | GLRLM_SRLGE | Average CT value | |
| Density uniformity | GLRLM_SRHGE | Minimum diameter on axial image(cm) | |
| Margin | NGLDM_Contrast | Lymph node enlargement | |
| GLZLM_HGZE | Margin | ||
| GLZLM_SZHGE | |||
| GLZLM_GLNU | |||
| GLZLM_ZLNU | |||
| DISCRETIZED_HUQ2 | |||
CM, combined model; GLCM, gray-level co-occurrence matrix; GLZLM, gray-level zone length matrix; GLRLM, gray-level run length matrix; NGLDM, neighborhood gray-level dependence matrix; RM, radiomics model.