Preoperatively predicting vessels encapsulating tumor clusters in hepatocellular carcinoma: Machine learning model based on contrast-enhanced computed tomography

Table 1 Characteristic baseline of patients in sets

Variables	Total set (n = 190)	Training set (n = 106)	Internal test set (n = 47)	External test set (n = 37)	P value
VETC (%)					0.986
Positive	94 (49)	53 (50)	23 (49)	18 (49)
Negative	96 (51)	53 (50)	24 (51)	19 (51)
Age (median, IQR)	57 (51, 66)	58.5 (51, 65.75)	56 (51.5, 67.5)	57 (50, 64)	0.708
Sex (%)					0.555
Male	153 (81)	83 (78)	38 (81)	32 (86)
Female	37 (19)	23 (22)	9 (19)	5 (14)
Hepatitis (%)					0.799
HBV or/and HCV	171 (90)	96 (91)	41 (87)	34 (92)
Negative	19 (10)	10 (9)	6 (13)	3 (8)
Cirrhosis (%)					0.008
Present	158 (83)	85 (80)	36 (77)	37 (100)
Absent	32 (17)	21 (20)	11 (23)	0 (0)
ALT (median, IQR)	32 (19, 51.75)	28 (18, 49)	40 (22.5, 63)	33 (22, 45)	0.094
AST (median, IQR)	37 (25, 61.5)	36.5 (23.25, 1.75)	49 (28.5, 78)	30 (24, 46)	0.041
GGT (median, IQR)	59.25 (31, 131.25)	61.75 (30, 127)	76 (38.5, 143.5)	49 (27, 98)	0.157
AFP (median, IQR)	49.06 (5.54, 9.25)	62.74 (6.62, 9.25)	56.78 (5.87, 16.5)	34.74 (5.22, 798)	0.516
Main tumor size (median, IQR)	5.7 (3.2, 9.28)	6.05 (3.02, 9.3)	6.9 (3.45, 11.15)	4.11 (3.2, 6.5)	0.098
Multiplicity (%)					0.037
≥ 2	46 (24)	29 (27)	14 (30)	3 (8)
1	144 (76)	77 (73)	33 (70)	34 (92)
Single lobe involvement (%)					0.064
Present	141 (74)	74 (70)	34 (72)	33 (89)
Absent	49 (26)	32 (30)	13 (28)	4 (11)
Intratumor hemorrhage (%)					0.179
Present	12 (6)	9 (8)	3 (6)	0 (0)
Absent	178 (94)	97 (92)	44 (94)	37 (100)
Intratumor necrosis (%)					0.131
Present	95 (50)	57 (54)	25 (53)	13 (35)
Absent	95 (50)	49 (46)	22 (47)	24 (65)
Arterial phase hyper enhancement (%)				0.701
Present	179 (94)	101 (95)	44 (94)	34 (92)
Absent	11 (6)	5 (5)	3 (6)	3 (8)
Well defined capsule (%)					0.143
Present	140 (74)	75 (71)	33 (70)	32 (86)
Absent	50 (26)	31 (29)	14 (30)	5 (14)
Washout (%)					0.249
Present	187 (98)	105 (99)	45 (96)	37 (100)
Absent	3 (2)	1 (1)	2 (4)	0 (0)
Non-smooth tumor margin (%)					0.435
Present	116 (61)	69 (65)	26 (55)	21 (57)
Absent	74 (39)	37 (35)	21 (45)	16 (43)

VETC: Vessels encapsulating tumor cluster; IQR: Interquartile range; HBV: Hepatitis B virus; HCV: Hepatitis C virus; ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; GGT: Gamma-glutamyl transferase; AFP: Alpha-fetoprotein.