Differentiation of focal liver lesions using three-dimensional ultrasonography: Retrospective and prospective studies

Table 1 Clinical characteristics of patients and focal liver lesions in retrospective and prospective studies (mean ± SD)

	Retrospective study (n = 163)				Prospective study (n = 119)
	HCC	Metastasis	Hemangioma	FNH	HCC	Metastasis	Hemangioma	FNH
No. of patients	98	35	24	6	70	28	16	5
No. of lesions	98	35	24	6	70	28	16	5
Age of patients (yr)	69.8 ± 6.5	64.8 ± 13.2	58.9 ± 11.2	54.2 ± 16.7	72.5 ± 7.3	69.2 ± 8.3	55.4 ± 14.1	52.8 ± 18.4
Liver cirrhosis
Child-Pugh class A	78	0	1	0	52	0	0	0
Child-Pugh class B	20	0	0	0	18	0	0	0
Lesion diameter (mm)	30.1 ± 24.3	28.9 ± 15.5	31.5 ± 18.0	38.4 ± 12.0	29.1 ± 20.4	30.7 ± 21.1	33.7 ± 16.7	37.4 ± 15.0
Final diagnosis
Surgery	11	15	2	0	6	12	0	0
Biopsy	29	20	0	1	19	16	0	1
Radiological imaging	58	0	22	5	45	0	16	4

HCC: Hepatocellular carcinoma; FNH: Focal nodular hyperplasia.

Table 2 Diagnostic criteria for focal liver lesions depicted by CE 2D US

Lesion	Enhancement patterns
	Early phase	Middle phase	Late phase
HCC	Intratumoral vessels with early homogeneous or heterogeneous enhancement, or intratumoral vessels alone	Homogeneous or heterogeneous enhancement	Hypoechoic lesion
Metastasis	Peritumoral vessels with early peripheral ring like enhancement	Peripheral ring like enhancement or perfusion defect	Hypoechoic lesion
Hemangioma	Peripheral nodular enhancement	Peripheral nodular enhancement, with centripetal progression	Isoechoic lesion, with centripetal progression
FNH	Spoke-wheel arteries with early homogeneous enhancement	Homogeneous enhancement	Isoechoic lesion with central scar

CE: Contrast-enhanced; 2D US: Two-dimensional ultrasonography.

Table 3 Enhancement patterns using CE 3D US in three phases: positive predictive value in retrospective study

Enhancement patterns						Positive predictive value
No.	Early phase		Middle phase	Late phase	Enhancement changes	HCC	Metastasis	Hemangioma	FNH
	Tumor enhancement	Tumoral vessels	Tumor enhancement	Tumor echogenicity
1	Diffuse	Intratumoral	Diffuse	Hypoechoic	Washout	0.98 (81)	0.01 (1)	0.01 (1)	0.00 (0)
2	Diffuse	Intratumoral	Diffuse	Isoechoic	Persistence	0.60 (3)	0.00 (0)	0.40 (2)	0.00 (0)
3	Diffuse	Intratumoral	Peripheral ring-like	Hypoechoic	Washout	0.33 (2)	0.67 (4)	0.00 (0)	0.00 (0)
4	Diffuse	Intratumoral	Perfusion defect	Hypoechoic	Washout	0.67 (2)	0.33 (1)	0.00 (0)	0.00 (0)
5	Diffuse	Spoke-wheel arteries	Diffuse	Isoechoic	Persistence	0.00 (0)	0.00 (0)	0.00 (0)	1.00 (6)
6	Peripheral ring-like enhancement	Intratumoral	Diffuse	Isoechoic	Persistence	1.00 (3)	0.00 (0)	0.00 (0)	0.00 (0)
7	Peripheral ring-like enhancement	Intratumoral	Peripheral ring-like	Hypoechoic	Washout	0.14 (1)	0.86 (6)	0.00 (0)	0.00 (0)
8	Peripheral ring-like enhancement	Peritumoral	Peripheral ring-like	Hypoechoic	Washout	0.00 (0)	1.00 (12)	0.00 (0)	0.00 (0)
9	Peripheral ring-like enhancement	Peritumoral	Perfusion defect	Hypoechoic	Washout	0.00 (0)	1.00 (3)	0.00 (0)	0.00 (0)
10	Peripheral nodular	Peritumoral	Diffuse	Isoechoic	Persistence	0.00 (0)	0.00 (0)	1.00 (1)	0.00 (0)
11	Peripheral nodular	Peritumoral	Peripheral nodular	Hypoechoic	Persistence	0.00 (0)	0.00 (0)	0.67 (2)	0.00 (0)
12	Peripheral nodular	Peritumoral	Peripheral nodular	Isoechoic	Persistence	0.00 (0)	0.00 (0)	1.00 (1)	0.00 (0)
13	Peripheral nodular	Peritumoral	Peripheral nodular	Hypoechoic	Washout	0.00 (0)	0.33 (1)	0.00 (0)	0.00 (0)
14	Peripheral nodular	Absence	Diffuse	Isoechoic	Persistence	0.00 (0)	0.00 (0)	1.00 (2)	0.00 (0)
15	Peripheral nodular	Absence	Peripheral nodular	Hypoechoic	Persistence	0.00 (0)	0.00 (0)	1.00 (8)	0.00 (0)
16	Peripheral nodular	Absence	Peripheral nodular	Isoechoic	Persistence	0.00 (0)	0.00 (0)	1.00 (5)	0.00 (0)
17	Absence	Intratumoral	Diffuse	Isoechoic	Persistence	1.00 (3)	0.00 (0)	0.00 (0)	0.00 (0)
18	Absence	Intratumoral	Diffuse	Hypoechoic	Washout	1.00 (1)	0.00 (0)	0.00 (0)	0.00 (0)
19	Absence	Intratumoral	Peripheral ring-like	Hypoechoic	Washout	0.00 (0)	1.00 (1)	0.00 (0)	0.00 (0)
20	Absence	Intratumoral	Perfusion defect	Hypoechoic	Washout	1.00 (1)	0.00 (0)	0.00 (0)	0.00 (0)
21	Absence	Peritumoral	Peripheral ring-like	Hypoechoic	Washout	0.00 (0)	1 .00(1)	0.00 (0)	0.00 (0)
22	Absence	Peritumoral	Perfusion defect	Hypoechoic	Washout	0.00 (0)	1.00 (3)	0.00 (0)	0.00 (0)
23	Absence	Absence	Perfusion defect	Hypoechoic	Absence	0.33 (1)	0.67 (2)	0.00 (0)	0.00 (0)
24	Absence	Absence	Peripheral nodular	Hypoechoic	Persistence	0.00 (0)	0.00 (0)	1.00 (2)	0.00 (0)

Positive predictive values are presented with number of lesions in parentheses.

Table 4 Sensitivity, specificity and A_z value for differential diagnosis based on CE 3D US in prospective study

Focal liver tumors	Diagnostic criteria based on combined enhancement patterns		Sensitivity	Specificity	Az value
HCC	1, 2, 4, 6, 17, 18, 20	Reader 1	91 (64/70)	90 (44/49)	0.94 (0.88-0.95)
		Reader 2	94 (66/70)	92 (45/49)	0.96 (0.91-0.98)
Metastasis	3, 7, 8, 9, 13, 19, 21, 22, 23	Reader 1	86 (24/28)	97 (88/91)	0.95 (0.89-0.98)
		Reader 2	82 (23/28)	96 (87/91)	0.94 (0.89-0.97)
Hemangioma	10, 11, 12, 14, 15, 16, 24	Reader 1	94 (15/16)	98 (101/103)	0.98 (0.94-1.00)
		Reader 2	88 (14/16)	97 (100/103)	0.97 (0.90-1.00)
FNH	5	Reader 1	80 (4/5)	98 (112/114)	0.99 (0.95-1.00)
		Reader 2	80 (4/5)	99 (113/114)	0.98 (0.87-1.00)

Combined enhancement patterns for diagnostic criteria are summarized according to the serial numbers in Table 3. Sensitivity and specificity data are presented as percentages with numbers of tumors in parentheses, and A_z values are presented with 95% confidence intervals in parentheses.

Table 5 Sensitivity, specificity and A_z value for differential diagnosis based on CE 2D US in prospective study

Lesion	Sensitivity	Specificity	Az value (95% CI)
HCC
Reader 1	89 (62/70)	88 (43/49)	0.95 (0.89-0.98)
Reader 2	94 (66/70)	86 (42/49)	0.95 (0.90-0.98)
Metastasis
Reader 1	86 (24/28)	96 (87/91)	0.93 (0.85-0.97)
Reader 2	82 (23/28)	98 (89/91)	0.95 (0.88-0.98)
Hemangioma
Reader 1	81 (13/16)	97 (100/103)	0.94 (0.80-0.99)
Reader 2	88 (14/16)	99 (102/103)	0.95 (0.73-1.00)
FNH
Reader 1	60 (3/5)	97 (111/114)	0.97 (0.74-1.00)
Reader 2	80 (4/5)	98 (112/114)	0.98 (0.66-1.00)

Sensitivity and specificity data are presented as percentages with numbers of tumors in parentheses.