Development and validation of a postoperative pulmonary infection prediction model for patients with primary hepatic carcinoma

Table 1 Baseline demographic and radiomics of patients with primary hepatic carcinoma

Variables	Training cohort			P value	Testing cohort			P value
	Overall, n = 353	Infection, n = 61	Non-infection, n = 292		Overall, n = 152	Infection, n = 25	Non-infection, n = 127
Age in yr
> 60	240 (68.0)	37 (60.7)	203 (69.5)	0.231	109 (71.7)	16 (64.0)	93 (73.2)	0.488
≤ 60	113 (32.0)	24 (39.3)	89 (30.5)		43 (28.3)	9 (36.0)	34 (26.8)
Sex
Male	234 (66.3)	39 (63.9)	195 (66.8)	0.78	106 (69.7)	18 (72.0)	88 (69.3)	0.975
Female	119 (33.7)	22 (36.1)	97 (33.2)		46 (30.3)	7 (28.0)	39 (30.7)
BMI
≤ 18.5	47 (13.3)	10 (16.4)	37 (12.7)	0.877	20 (13.2)	4 (16.0)	16 (12.6)	0.627
18.5-23.9	121 (34.3)	21 (34.4)	100 (34.2)		54 (35.5)	6 (24.0)	48 (37.8)
24.0-27.9	97 (27.5)	16 (26.2)	81 (27.7)		47 (30.9)	9 (36.0)	38 (29.9)
≥ 28.0	88 (24.9)	14 (23.0)	74 (25.3)		31 (20.4)	6 (24.0)	25 (19.7)
Smoking
Yes	114 (32.3)	19 (31.1)	95 (32.5)	0.952	63 (41.4)	14 (56.0)	49 (38.6)	0.163
No	239 (67.7)	42 (68.9)	197 (67.5)		89 (58.6)	11 (44.0)	78 (61.4)
Drinking
Yes	100 (28.3)	18 (29.5)	82 (28.1)	0.945	56 (36.8)	8 (32.0)	48 (37.8)	0.747
No	253 (71.7)	43 (70.5)	210 (71.9)		96 (63.2)	17 (68.0)	79 (62.2)
History of hepatitis B
Yes	134 (38.0)	27 (44.3)	107 (36.6)	0.332	58 (38.2)	10 (40.0)	48 (37.8)	1.000
No	219 (62.0)	34 (55.7)	185 (63.4)		94 (61.8)	15 (60.0)	79 (62.2)
History of hepatitis C
Yes	129 (36.5)	22 (36.1)	107 (36.6)	1	50 (32.9)	9 (36.0)	41 (32.3)	0.898
No	224 (63.5)	39 (63.9)	185 (63.4)		102 (67.1)	16 (64.0)	86 (67.7)
Hypertension
Yes	110 (31.2)	19 (31.1)	91 (31.2)	1	57 (37.5)	11 (44.0)	46 (36.2)	0.611
No	243 (68.8)	42 (68.9)	201 (68.8)		95 (62.5)	14 (56.0)	81 (63.8)
Diabetes
Yes	119 (33.7)	21 (34.4)	98 (33.6)	1	52 (34.2)	9 (36.0)	43 (33.9)	1.000
No	234 (66.3)	40 (65.6)	194 (66.4)		100 (65.8)	16 (64.0)	84 (66.1)
Cirrhosis
Yes	176 (49.9)	32 (52.5)	144 (49.3)	0.76	68 (44.7)	7 (28.0)	61 (48.0)	0.105
No	177 (50.1)	29 (47.5)	148 (50.7)		84 (55.3)	18 (72.0)	66 (52.0)
Child-Pugh
A	253 (71.7)	39 (63.9)	214 (73.3)	0.187	102 (67.1)	14 (56.0)	88 (69.3)	0.289
B	100 (28.3)	22 (36.1)	78 (26.7)		50 (32.9)	11 (44.0)	39 (30.7)
AFP in mg/L
≤ 100	206 (58.4)	27 (44.3)	179 (61.3)	0.021	89 (58.6)	11 (44.0)	78 (61.4)	0.163
> 100	147 (41.6)	34 (55.7)	113 (38.7)		63 (41.4)	14 (56.0)	49 (38.6)
HBV DNA
Negative	233 (66.0)	41 (67.2)	192 (65.8)	0.944	106 (69.7)	15 (60.0)	91 (71.7)	0.357
Positive	120 (34.0)	20 (32.8)	100 (34.2)		46 (30.3)	10 (40.0)	36 (28.3)
Tumor size in cm
≤ 4	203 (57.5)	24 (39.3)	179 (61.3)	0.003	83 (54.6)	6 (24.0)	77 (60.6)	0.002
> 4	150 (42.5)	37 (60.7)	113 (38.7)		69 (45.4)	19 (76.0)	50 (39.4)
Treatment
Laparoscopic	95 (26.9)	17 (27.9)	78 (26.7)	0.979	45 (29.6)	8 (32.0)	37 (29.1)	0.962
Open	258 (73.1)	44 (72.1)	214 (73.3)		107 (70.4)	17 (68.0)	90 (70.9)
LNM
Yes	108 (30.6)	17 (27.9)	91 (31.2)	0.722	48 (31.6)	7 (28.0)	41 (32.3)	0.853
No	245 (69.4)	44 (72.1)	201 (68.8)		104 (68.4)	18 (72.0)	86 (67.7)
Energy	4.48 (2.97, 5.91)	9.05 (7.07, 10.30)	4.02 (2.62, 5.26)	< 0.001	4.52 (2.74, 6.02)	8.82 (6.99, 10.91)	4.01 (2.45, 5.38)	< 0.001
Contrast	351.00 (316.00, 384.00)	289.00 (275.00, 301.00)	360.00 (334.00, 391.75)	< 0.001	347.00 (319.50, 381.00)	306.00 (275.00, 317.00)	355.00 (331.00, 388.00)	< 0.001
Correlation	16.39 (12.49, 20.01)	13.77 (11.43, 19.07)	16.70 (13.04, 20.11)	0.006	16.63 (12.02, 20.33)	18.08 (14.70, 21.30)	16.07 (11.96, 20.02)	0.093
SOS	0.89 (0.71, 1.08)	2.38 (2.01, 2.97)	0.83 (0.69, 0.97)	< 0.001	0.86 (0.73, 1.06)	2.61 (2.11, 3.06)	0.84 (0.69, 0.96)	< 0.001
IND	1.46 (1.17, 1.85)	3.43 (2.83, 4.07)	1.38 (1.12, 1.67)	< 0.001	1.52 (1.15, 1.90)	3.73 (3.11, 4.11)	1.44 (1.12, 1.69)	< 0.001
MES	2.77 (1.95, 3.47)	5.24 (4.60, 5.92)	2.50 (1.86, 3.12)	< 0.001	2.55 (1.96, 3.47)	4.90 (4.21, 5.93)	2.38 (1.89, 3.04)	< 0.001
SUV	20.10 (15.70, 25.60)	56.00 (39.50, 72.00)	18.60 (15.20, 22.83)	< 0.001	21.60 (16.67, 25.22)	61.80 (39.00, 70.10)	19.50 (15.70, 23.65)	< 0.001
SUE	21.80 (16.60, 27.00)	45.30 (37.20, 55.10)	19.85 (16.10, 24.00)	< 0.001	21.40 (15.97, 26.40)	46.60 (35.20, 53.30)	20.00 (15.45, 24.35)	< 0.001
Entropy	0.84 (0.62, 1.07)	2.07 (1.51, 2.44)	0.76 (0.58, 0.94)	< 0.001	0.82 (0.60, 1.10)	1.84 (1.45, 2.03)	0.73 (0.56, 0.94)	< 0.001
DIV	316.00 (210.00, 404.00)	295.00 (193.00, 402.00)	318.50 (224.50, 404.00)	0.411	296.50 (196.50, 391.75)	300.00 (191.00, 362.00)	296.00 (207.50, 400.50)	0.800
DIE	234.00 (188.00, 274.00)	244.00 (181.00, 274.00)	229.00 (188.00, 274.00)	0.774	232.50 (189.75, 274.50)	245.00 (204.00, 283.00)	231.00 (188.50, 271.50)	0.571

Data are presented as n (%) or median (interquartile range). AFP: Alpha-fetoprotein; BMI: Body mass index; DIE: Difference entropy; DIV: Difference variance; HBV: Hepatitis B virus; IND: Inverse difference; LNM: Lymph node metastasis; MES: Mean sum; SOS: Sum of squares; SUE: Sum entropy; SUV: Sum variance.

Table 2 Comparison of predictive efficacy of pulmonary infection prediction models via receiver operating characteristic curves

Model	Training set			Internal validation set
	AUC mean	AUC 95%CI	Variables1	AUC mean	AUC 95%CI	Variables1
RFM	0.823	0.766-0.880	7	0.801	0.744-0.858	7
ANNM	0.815	0.766-0.864	8	0.787	0.738-0.836	8
GLRM	0.766	0.717-0.815	6	0.734	0.677-0.791	6

¹Variables included in the model.

ANNM: Artificial neural network model; AUC: Area under the curve; CI: Confidence interval; GLRM: Generalized linear regression model; RFM: Random forest model.