Breast non-mass-like lesions on contrast-enhanced ultrasonography: Feature analysis, breast image reporting and data system classification assessment

Table 1 Pathology of 51 non-mass-like lesions

Pathology	Numbers
A1 group	25
Adenosis	17
Intraductal papilloma	5
Plasma cell mastitis	2
Vascular smooth muscle hamartoma	1
A2 group	3
Sclerosing adenosis	1
Epithelial columnar cell lesion	1
Atypical ductal or lobular hyperplasia	1
B group	23
Intraductal carcinoma in situ	14
Invasive ductal carcinoma	7
Invasive lobular carcinoma	1
Mucous carcinoma	1

Table 2 Clinical information and ultrasonography, and color Doppler flow imaging between benign and malignant non-mass-like lesions

Parameter		Pathology, n (%)		Total	χ2	P value
		Benign	Malignant
Age in yr	﹤45	18 (64.29)	9 (39.13)	27 (52.94)	3.207	0.073
	≥ 45	10 (35.71)	14 (60.87)	24 (47.06)
Palpability	No	19 (67.86)	12 (52.17)	31 (60.78)	1.303	0.254
	Yes	9 (32.14)	11 (47.83)	20 (39.22)
Nipple discharge	No	20 (71.43)	18 (78.26)	38 (74.51)	0.31	0.577
	Yes	8 (28.57)	5 (21.74)	13 (25.49)
Echogenicity	Hypo-echoic	14 (50.00)	13 (56.52)	27 (52.94)	0.216	0.642
	Mixed-echoic	14 (50.00)	10 (43.48)	24 (47.06)
Ductal changes	No	17 (60.71)	12 (52.17)	29 (56.86)	0.375	0.54
	Yes	11 (39.29)	11 (47.83)	22 (43.14)
Rear echo attenuation	No	25 (89.29)	16 (69.57)	41 (80.39)	1.99	0.158
	Yes	3 (10.71)	7 (30.43)	10 (19.61)
Architectural distortion	No	27 (96.43)	17 (73.91)	44 (86.27)	1.043	0.307
	Yes	1 (3.57)	6 (26.09)	7 (13.73)
Microcalcifications	No	24 (85.71)	10 (43.48)	34 (66.67)	10.137	0.001b
	Yes	4 (14.29)	13 (56.52)	17 (33.33)
Axillary lymph node	Normal	26 (92.86)	17 (73.91)	43 (84.31)	1.274	0.237
	Abnormal	2 (7.14)	6 (26.09)	8 (15.69)
CDFI	Scarce	19 (67.86)	14 (60.87)	33 (64.71)	0.27	0.603
	Abundant	9 (32.14)	9 (39.13)	18 (35.29)

^bP < 0.01. CDFI: Color Doppler flow imaging.

Table 3 Contrast-enhanced ultrasound imaging between benign and malignant non-mass-like lesions

Parameter		Pathology, n (%)		Total	χ2	P value
		Benign	Malignant
	Later	5 (17.86)	0 (0.00)	5 (9.80)
Enhancement time	Synchronous	17 (60.71)	9 (39.13)	26 (51.98)	10.270	0.006b
	Earlier	6 (21.43)	14 (60.87)	20 (39.22)
	Hypo-enhanced	7 (25.00)	3 (13.04)	10 (19.61)
Enhanced intensity	Iso-enhanced	15 (53.57)	4 (17.39)	19 (37.25)	12.140	0.002b
	Hyper-enhanced	6 (21.43)	16 (69.57)	22 (43.14)
	Diffuse enhancement	20 (71.43)	18 (78.26)	38 (74.51)
Enhancement direction	Centripetal	4 (14.29)	2 (8.70)	6 (11.76)	0.429	0.807
	Centrifugal	4 (14.29)	3 (13.04)	7 (13.73)
Enhancement mode	Homogeneous	22 (78.57)	15 (65.22)	37 (72.55)	1.131	0.288
	Heterogeneous	6 (21.43)	8 (34.78)	14 (27.45)
Lesion range	Without increase	26 (92.86)	8 (34.8)	34 (66.67)	22.288	0.000b
	Increase	2 (7.14)	15 (65.2)	17 (33.33)
Regression time	Later	8 (28.57)	11 (47.83)	19 (37.25)	2.921	0.232
	Synchronous	15 (53.57)	7 (30.43)	22 (43.14)
	Earlier	5 (17.86)	5 (21.74)	10 (19.61)
Peripheral blood vessels	No	21 (75)	11 (47.83)	32 (62.75)	3.989	0.046a
	Yes	7 (25)	12 (52.17)	19 (37.25)

^aP < 0.05;

^bP < 0.01.

Table 4 Protocol for readjusting the Breast Imaging Reporting and Data System category with contrast-enhanced ultrasound

Initial category	Number of independent risk factors	Modified BI-RADS category
BI-RADS 4a	0	Reduce to 3 category
	1	Remains unchanged
	2	Increase one category
BI-RADS 4b	0	Reduce to 3 category
	1	Remains unchanged
	2	Increase one category
BI-RADS 4c	0	Reduce to 4a category
	1 or 2	Increase to 5 category

BI-RADS: Breast Imaging Reporting and Data System.

Table 5 Comparison of initial Breast Imaging Reporting and Data System category, and readjusted Breast Imaging Reporting and Data System category with pathology results

Methods	BI-RADS category	Total, n (%)	Pathology, n (%)
			Benign	Malignant
US	4a	24 (47.06)	20 (71.43)	4 (19.61)
	4b	10 (19.61)	4 (14.29)	6 (19.61)
	4c	17 (33.33)	4 (14.29)	13 (19.61)
CEUS + BI-RADS	3	19 (37.25)	18 (78.26)	1 (4.35)
	4a	8 (15.691)	7 (25.00)	1 (4.35)
	4b	7 (13.73)	1 (3.57)	5 (21.74)
	4c	5 (9.80)	1 (3.57)	5 (21.74)
	5	12 (23.53)	1 (3.57)	11 (47.83)

US: Ultrasonography; BI-RADS: Breast Imaging Reporting and Data System; CEUS: Contrast-enhanced ultrasound.

Table 6 Diagnostic performance of ultrasonography, ultrasonography + contrast-enhanced ultrasound and contrast-enhanced ultrasound + Breast Imaging Reporting and Data System

Methods	AUC	Sensitivity	Specificity	PPV	NPV	Accuracy	Youden’s index
US	0.752	0.826	0.741	0.704	0.833	0.765	0.536
US + CEUS	0.877	0.870	0.929	0.909	0.879	0.902	0.797
CEUS + BI-RADS	0.903	0.913	0.892	0.875	0.926	0.902	0.800

US: Ultrasonography; CEUS: Contrast-enhanced ultrasound; BI-RADS: Breast Imaging Reporting and Data System; AUC: Area under the curve; NPV: Negative predictive value; PPV: Positive predictive value.