Magnetic resonance imaging-based radiomics signature for predicting preoperative staging of esophageal cancer

Table 1 Clinical and pathological characteristics of 210 esophageal cancer patients

Characteristics	Primary cohort		P value	Validation cohort		P value
	Stage I-II	Stage III-IV		Stage I-II	Stage III-IV
Age (years)	62.0	61.0	0.548	62.5	64.0	0.842
Gender			0.073			0.613
Male	50	63		24	28
Female	21	13		6	5
Location			0.33			0.705
Upper	2	6		2	2
Middle	47	51		17	22
Lower	22	19		11	9

Table 2 Selected radiomics features of esophageal cancer patients

Task	MRI	Feature name	Coefficient
Tumor node metastasis stage prediction	T2WI
		Original_firstorder_Median	0.921642536
		Original_shape_Elongation	0.967002183
		Original_glcm_Correlation	0.246781324
	T1WI-Gd
		Original_shape_LeastAxisLength	0.875999143
		Original_shape_Elongation	0.967002356
		Original_glcm_DifferenceAverage	0.109732763
		Original_firstorder_Kurtosis	0.605404872
		Original_firstorder_Median	0.921642536
		Original_glszm_LowGrayLevelZoneEmphasis	0.274812737
		Original_glcm_Imc1	0.638235237
		Original_gldm_LargeDependenceHighGrayLevelEmphasis	0.209360630
		Original_shape_MajorAxisLength	0.149464274
		Original_ngtdm_Strength	0.214134941
		Original_glcm_Idn	0.983044251
		Original_firstorder_10Percentile	0.303070619
		Original_glszm_SizeZoneNonUniformity	0.126542445
		Original_ngtdm_Complexity	0.524606933

MRI: Magnetic resonance imaging; T1WI: T1-weighted imaging; T2WI: T2-weighted imaging.

Table 3 Delong test results in the primary and validation cohort

Model	Primary cohort			Validation cohort
	T2WI	T1WI	Combined	T2WI	T1WI	Combined
T2WI	0	0.081	0.0035	0	0.27	0.09
T1WI	-1.74	0	0.19	-1.09	0	0.80
Combined	-2.95	-1.30	0	-1.65	-0.25	0

T1WI: T1-weighted imaging; T2WI: T2-weighted imaging.

Table 4 Model performance for predicting tumor node metastasis stages in esophageal cancer patients

Model	Primary cohort			Validation cohorts
	AUC (95%CI)	SEN (95%CI)	SPE (95%CI)	AUC (95%CI)	SEN (95%CI)	SPE (95%CI)
T2WI	0.788 (0.712, 0.858)	0.75 (0.642, 0.834)	0.746 (0.634, 0.833)	0.779 (0.651, 0.892)	0.667 (0.496, 0.803)	0.8 (0.627, 0.905)
T1WI	0.859 (0.799, 0.919)	0.829 (0.729, 0.897)	0.789 (0.681, 0.868)	0.844 (0.728, 0.941)	0.636 (0.466, 0.778)	0.8 (0.627, 0.905)
Combined	0.877 (0.819, 0.929)	0.842 (0.744, 0.907)	0.761 (0.65, 0.845)	0.851 (0.739, 0.948)	0.697 (0.527, 0.826)	0.8 (0.627, 0.905)

95%CI: 95% confidence interval; T1WI: T1-weighted imaging; T2WI: T2-weighted imaging; AUC: Area under the curve; SEN: Sensitivity; SPE: Specificity.