Multiphase convolutional dense network for the classification of focal liver lesions on dynamic contrast-enhanced computed tomography

Table 1 The basic information and detail distribution of each dataset

		Training set	Test set	P value
Category A: HCC	No. of lesions/No. of patients	88/79	23/22
	Age (median [range]) in yr	49 (24-81)	49.5 (33-70)	0.726
	Sex (percentage of women)	6/79 (7.6%)	5/22 (22.7%)	0.044
	Size of lesion (mean ± SD) in mm	60.6 ± 36.3	63.0 ± 45.4	0.789
	Histopathologic diagnosis (No. of lesions/No. of patients)
	Surgery	79/70	20/19
	Biopsy	9/9	3/3
Category B: Metastases	No. of lesions/No. of patients	89/34	23/14
	Age (Median [range]) (yr)	58.5 (23-79)	58 (23-79)	0.937
	Sex (Percentage of women)	8/34 (23.5%)	6/14 (42.9%)	0.181
	Size of lesion (mean ± SD) in mm	23.0 ± 13.9	22.7 ± 11.5	0.937
	Primary tumors (No. of lesions/No. of patients)
	Colorectal cancer	40/20	10/6
	Gastric carcinoma	13/3	3/2
	Breast cancer	2/1	0/0
	Lung cancer	14/4	4/2
	Thyroid cancer	16/4	4/2
	Malignant jejunal stromal tumor	2/1	1/1
	Duodenal papillary carcinoma	0/0	1/1
	Laryngocarcinoma	2/1	0/0
Category C: Benign non-inflammatory FLLs	No. of lesions/No. of patients	128/97	34/32
	Age (median [range]) in yr	34 (17-82)	34 (10-74)	0.729
	Sex (percentage of women)	52/97 (53.6%)	16/32 (50.0%)	0.723
	Size of lesion (mean ± SD) in mm	41.9 ± 30.5	52.9 ± 28.4	0.060
	Histological type (No. of lesions/No. of patients)
	Hemangioma	55/35	15/15
	FNH	67/58	17/15
	Adenoma	6/4	2/2
Category D: Hepatic abscesses	No. of lesions/No. of patients	105/77	27/20
	Age (median [range]) in yr	54 (4-82)	55 (25-82)	0.936
	Sex (percentage of women)	24/77 (31.2%)	7/20 (35.0%)	0.743
	Size of lesion (mean ± SD) in mm	64.5 ± 34.9	63.8 ± 24.2	0.916

FLLs: Focal liver lesions; FNH: Focal nodular hyperplasias.

Table 2 The confusion matrix analysis on test set

		Ground truth				Positive predictive value
		Benign	Metastases	HCCs	Hepatic abscesses
		non-inflammatory FLLs
Prediction	Benign non-inflammatory FLLs	25	0	4	2	0.806
	Metastases	3	23	2	3	0.742
	HCCs	3	0	17	0	0.85
	Hepatic abscesses	3	0	0	22	0.88
	Sensitivity	0.735	1	0.739	0.815
	Specificity	0.918	0.905	0.964	0.963
	Accuracy	0.86	0.925	0.916	0.925
	Mean accuracy	0.813

HCCs: Hepatocellular carcinomas; FLLs: Focal liver lesions.

Table 3 The model's performance comparison between the normal set and “phase cheating” sets

Policy	HCCs (AUC [95%CI]/P value)	Metastases (AUC [95%CI]/P value)	Benign non-inflammatory (AUC [95%CI]/P value)	Hepatic Abscesses (AUC [95%CI]/P value)
PP + AP + PVP + DP	0.92 (0.837-0.992)	0.99 (0.967-1.00)	0.88 (0.795-0.955)	0.96 (0.914-0.996)
AP + AP + PVP + DP	0.820 (0.705-0.905)/0.0699	0.901 (0.805- 0.960)/0.0289	0.893 (0.809-0.949)/0.2502	0.924 (0.823-0.977)/0.3387
PP + PVP + PVP + DP	0.704 (0.565-0.821)/0.0017	0.930 (0.832- 0.981)/0.2573	0.799 (0.701- 0.877)/0.0924	0.938 (0.846-0.984)/0.4317
PP + AP + AP + DP	0.768 (0.643-0.866)/0.0013	0.833 (0.714 -0.916)/0.0120	0.864 (0.774-0.929)/0.9720	0.935 (0.846-0.981)/0.4047
PP + AP+ PVP + PVP	0.911 (0.815-0.967)/0.6404	0.959 (0.882- 0.992)/0.4066	0.913 (0.832-0.963)/0.7877	0.831 (00.716- 0.914)/0.0184
PP + AP + AP + AP	0.672 (0.542-0.785)/< 0.0001	0.758 (0.692- 0.909)/0.0079	0.863 (0.773-0.927)/0.3188	0.806 (0.690- 0.893)/0.0475
PP + PVP + PVP + PVP	0.721 (0.584-0.834)/0.0019	0.913 (0.807-0.972)/0.1165	0.775 (0.675-0.857)/ 0.0247	0.900 (0.796- 0.962)/0.7491
PP + DP+ DP+ DP	0.652 (0.513-0.774)/0.0002	0.818 (0.692-0.909)/0.0079	0.790 (0.688-0.870)/0.0356	0.904 (0.802-0.964)/0.7911
AP + AP + AP + AP	0.573 (0.443- 0.696)/< 0.0001	0.674 (0.548-0.785)/< 0.0001	0.833 (0.739- 0.904)/0.3375	0.697 (0.567- 0.807)/0.0019
PVP + PVP + PVP+ PVP	0.697 (0.554-0.817)/0.0029	0.859 (0.748- 0.934)/0.0101	0.794 (0.693- 0.874)/0.1144	0.782 (0.650-0.882)/0.0278
DP + DP + DP + DP	0.697 (0.562- 0.811)/0.0007	0.787 (0.666- 0.880)/0.0008	0.751 (0.646-0.838)/0.0387	0.873 (0.760-0.946)/0.1805

AP: Arterial phase; AUC: Area under the receiver operating characteristic curve; CI: Confidence interval; DP: Delayed phase; FLLs: Focal liver lesions; HCC: Hepatocellular carcinoma; PP: Precontrast phase; PVP: Portal venous phase.