Multiparameter magnetic resonance imaging-based radiomics model for the prediction of rectal cancer metachronous liver metastasis

Table 1 Patient baseline characteristics and magnetic resonance imaging radiomics parameters, n (%)

Variables	Overall (n = 301)	MLM (n = 49)	Non-MLM (n = 252)	P value
Age [median (IQR)]	46.00 (31.00, 58.00)	51.00 (32.00, 60.00)	44.50 (30.00, 57.00)	0.074
Gender
Male	136 (45.2)	22 (44.9)	114 (45.2)	1.000
Female	165 (54.8)	27 (55.1)	138 (54.8)
BMI, kg/m2 [median (IQR)]	23.50 (20.80, 26.10)	22.90 (20.70, 26.60)	23.55 (20.80, 26.02)	0.870
Smoking
Yes	140 (46.5)	26 (53.1)	114 (45.2)	0.396
No	161 (53.5)	23 (46.9)	138 (54.8)
Drinking
Yes	142 (47.2)	22 (44.9)	120 (47.6)	0.847
No	159 (52.8)	27 (55.1)	132 (52.4)
MTD, cm
≤ 4	147 (48.8)	25 (51.0)	122 (48.4)	0.859
> 4	154 (51.2)	24 (49.0)	130 (51.6)
Pathological grade
I-II	142 (47.2)	17 (34.7)	125 (49.6)	0.079
III	159 (52.8)	32 (65.3)	127 (50.4)
Pathological type
Infiltrating	38 (12.6)	4 (8.2)	34 (13.5)	0.700
Ulcerative	111 (36.9)	18 (36.7)	93 (36.9)
Cauliflower	74 (24.6)	12 (24.5)	62 (24.6)
Uplift	78 (25.9)	15 (30.6)	63 (25.0)
MRF
Yes	162 (53.8)	23 (46.9)	139 (55.2)	0.368
No	139 (46.2)	26 (53.1)	113 (44.8)
EMVI
Yes	154 (51.2)	26 (53.1)	128 (50.8)	0.893
No	147 (48.8)	23 (46.9)	124 (49.2)
Node
Yes	133 (44.2)	26 (53.1)	107 (42.5)	0.226
No	168 (55.8)	23 (46.9)	145 (57.5)
Spicule
Yes	164 (54.5)	28 (57.1)	136 (54.0)	0.801
No	137 (45.5)	21 (42.9)	116 (46.0)
AFP, ng/mL [median (IQR)]	2.81 (2.25, 3.41)	2.69 (2.16, 3.32)	2.82 (2.27, 3.42)	0.334
CA199, U/mL [median (IQR)]	9.61 (6.60, 12.66)	9.83 (6.64, 11.47)	9.59 (6.54, 12.73)	0.856
CEA, ng/mL [median (IQR)]
0-5	167 (55.5)	14 (28.6)	153 (60.7)	< 0.001
≥ 5	134 (44.5)	35 (71.4)	99 (39.3)
pT stage
T2	158 (52.5)	30 (61.2)	128 (50.8)	0.237
T3	143 (47.5)	19 (38.8)	124 (49.2)
N stage
N0	94 (31.2)	16 (32.7)	78 (31.0)	0.936
N1	102 (33.9)	17 (34.7)	85 (33.7)
N2	105 (34.9)	16 (32.7)	89 (35.3)
Character 1 [median (IQR)]	0.46 (0.31, 0.63)	1.65 (1.44, 1.98)	0.41 (0.28, 0.55)	< 0.001
Character 2 [median (IQR)]	8.70 (7.70, 9.60)	13.00 (11.80, 14.80)	8.30 (7.57, 9.10)	< 0.001
Character 3 [median (IQR)]	169.30 (140.90, 198.10)	167.80 (145.20, 194.70)	172.25 (139.95, 198.25)	0.976
Character 4 [median (IQR)]	1.70 (1.20, 2.40)	4.50 (3.60, 5.10)	1.60 (1.10, 2.10)	< 0.001
Character 5 [median (IQR)]	3.60 (2.90, 4.20)	6.70 (4.80, 8.80)	3.40 (2.70, 4.00)	< 0.001
Character 6 [median (IQR)]	32.30 (22.30, 42.50)	29.80 (23.00, 39.30)	32.75 (22.08, 43.00)	0.364
Character 7 [median (IQR)]	4.20 (2.80, 5.30)	7.20 (5.90, 8.10)	3.75 (2.60, 4.80)	< 0.001

MLM: Metachronous liver metastasis; IQR: Interquartile range; BMI: Body mass index; MTD: Maximum tumor diameter; MRF: Mesenteric fascia; EMVI: Extramural venous invasion; AFP: Alpha fetoprotein; CA199: Carbohydrate antigen 199; CEA: Carcinoembryonic antigen; Character 1: T2_wavelet.LHL_firstorder_RobustMeanAbsoluteDeviation; Character 2: T1_log.sigma10.mm.3D_firstorder_Kurtosis; Character 3: T1_lbp.3D.m1_firstorder_Skewness; Character 4: ADC_wavelet.LHL_gldm_LargeDepenceHighGrayLevelEmphasis; Character 5: ADC_wavelet.HLL_glrlm_LongRunHighGrayLeveEmphasis; Character 6: T1_log.sigma30.mm.3D_glrlm_GrayLevelNonUniformity; Character 7: T1_wavelet.HHL_glszm_GrayLevelNonUniformity.