Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning

Table 1 Comparative analysis of clinical indicators and spectral computed tomography parameters between groups

Variables	Training cohort (n = 172)			Validation cohort (n = 85)
	LVI/PNI (+)	LVI/PNI (-)	P value	LVI/PNI (+)	LVI/PNI (-)	P value
Gender, n (%)
Male	77 (61.1)	49 (38.9)	0.818	47 (70.2)	20 (29.8)	0.109
Female	29 (63.0)	17 (37.0)		9 (50.0)	9 (50.0)
Age, yr, n (%)
< 60	33 (66.0)	17 (34.0)	0.450	19 (67.9)	9 (32.1)	0.788
≥ 60	73 (59.8)	49 (40.2)		37 (64.9)	20 (35.1)
CT-T
T1/2	23 (30.3)	53 (69.7)	< 0.001a	9 (28.1)	23 (71.9)	< 0.001a
T3/4	83 (86.5)	13 (13.5)		47 (88.7)	6 (11.3)
CT-N
N0	29 (34.9)	54 (65.1)	< 0.001a	19 (55.8)	24 (44.2)	< 0.001a
N1/2/3	77 (86.5)	12 (13.5)		36 (12.2)	5 (87.8)
CT-EMVI
Negative	44 (41.5)	62 (58.5)	< 0.001a	20 (45.5)	24 (54.5)	< 0.001a
Positive	62 (6.1)	4 (93.9)		36 (87.8)	5 (12.2)
CA72-4, n (%)
Negative	86 (57.3)	64 (42.7)	0.002a	46 (63.9)	26 (36.1)	0.528
Positive	20 (90.9)	2 (9.1)		10 (76.9)	3 (23.1)
AFP, n (%)
Negative	104 (61.5)	65 (38.5)	1.000	54 (65.9)	28 (34.1)	1.000
Positive	2 (66.7)	1 (33.3)		2 (66.7)	1 (33.3)
CEA, n (%)
Negative	91 (61.1)	58 (38.9)	0.704	42 (61.8)	26 (38.2)	0.109
Positive	15 (65.2)	8 (34.8)		14 (82.4)	3 (17.6)
CA199, n (%)
Negative	89 (58.6)	63 (41.4)	0.022a	48 (64.0)	27 (36.0)	0.483
Positive	17 (85.0)	3 (15.0)		8 (80.0)	2 (20.0)
CA125, n (%)
Negative	101 (60.5)	66 (39.5)	0.158	54 (65.9)	28 (34.1)	1.000
Positive	5 (100.0)	0 (0.0)		2 (66.7)	1 (33.3)
VP-70 kev, mean ± SD	92.46 ± 18.29	64.54 ± 15.90	< 0.001a	89.87 ± 20.34	66.30 ± 18.65	< 0.001a
EP-NIC, mean ± SD	0.68 ± 0.16	0.49 ± 0.13	< 0.001a	0.69 ± 0.15	0.51 ± 0.12	< 0.001a

^aP value < 0.05.

P was calculated from univariate association of characteristics with lymphovascular invasion/perineural invasion status in gastric cancer cohorts. LVI: Lymphovascular invasion; PNI: Perineural invasion; (+): Positive; (-): Negative; CT-EMVI: Computed tomography-detected extramural vein invasion; VP-70 keV: Single-energy computed tomography value of 70 keV in the venous phase; EP-NIC: Ratio of the standardized iodine concentration in the equilibrium phase; CA: Cancer antigen; CEA: Carcinoembryonic antigen; AFP: Alfa fetoprotein.