Value of Histogram of Gray-Scale Ultrasound Image in Differential Diagnosis of Small Triple Negative Breast Invasive Ductal Carcinoma and Fibroadenoma

Figures & data

Figure 1 Flowchart of the patient selection process in current study.

Figure 2 A 69-year-old woman with TN-IDC in the left breast. (A) and (B) An ROI for the oval hypoechoic mass in the grey-scale US image. (C) Grey-scale histogram of the tumor. The values of grey-scale histogram parameters are as follows: mean, 52.86; variance, 330.42; skewness, 0.48255; and kurtosis, 0.81965; 1st percentile, 13; 10th percentile, 31; 50th percentile, 52; 90th percentile, 76; and 99th percentile, 106. (D) HE staining showed obvious tumor cell atypia with hemorrhage and necrosis, vacuolar nuclear chromatin, obvious nucleolus, fibrous connective tissue reaction and inflammatory cell infiltration (HE×100). (E) Negative expression of ER in the tumor cells (IHC×100). (F) Negative expression of PR in the tumor cells (IHC × 100). (G) Negative expression of HER-2 in the tumor cells (IHC×100).

Abbreviations: TN-IDC, triple negative breast invasive ductal carcinoma; ROI, region of interest; HE, hematoxylin and eosin; IHC, immunohistochemistry; ER, estrogen receptor; PR, progesterone receptor; HER-2, human epidermal growth factor receptor 2.

Figure 3 A 47-year-old woman with FA in the right breast. (A and B) An ROI for the oval hypoechoic mass in the grey-scale US image. (C) Grey-scale histogram of the tumor. The values of grey-scale histogram parameters are as follows: mean, 96.701; variance, 580.27; skewness, 0.40754; and kurtosis, 0.59665; 1st percentile, 46; 10th percentile, 67; 50th percentile, 96; 90th percentile, 126; and 99th percentile, 164. (D) Microscopically, spindle cells in the stroma are nodular hyperplasia with mucus degeneration, and the compressed duct is fissure (HE×100).

Abbreviations: FA, fibroadenoma; ROI, region of interest; HE, hematoxylin and eosin.

Table 1 Clinicopathologic Characteristics of 57 FAs and 55 TN-IDCs

Characteristics	FA (n=57)	TN-IDC (n=55)	P value
Mean age, years*	40.98±12.52	43.64±12.57	0.266
Tumor size, cm*	1.28±0.37	1.27±0.33	0.898
Clinical symptom^†			0.460
Asymptomatic	34	29
Pain or palpable	23	26

Notes: *Data are mean values±standard deviations. Data were tested using the Student’s t-test. ^†Data were tested using the chi-square test.

Table 2 Interreader ICC Values for the Measurements of Histogram Parameters Between Two Readers

Parameters	Interreader ICC (95% CI)
Mean	0.999 (0.999–0.999)
Variance	0.984 (0.977–0.989)
Skewness	0.959 (0.941–0.972)
Kurtosis	0.883 (0.834–0.918)
1%	0.998 (0.998–0.999)
10%	0.999 (0.998–0.999)
50%	0.999 (0.999–1.000)
90%	0.996 (0.994–0.997)
99%	0.989 (0.985–0.993)

Abbreviation: CI, confidence interval.

Table 3 Comparison of Histogram Parameters Between FA Group and TN-IDC Group

Parameters	FA* (n=57)	TN-IDC* (n=55)	P value
Mean	75.61±31.81	38.22±17.90	<0.001
Variance	482.40±228.89	460.15±278.32	0.644
Skewness	0.58±0.64	0.78±0.64	0.110
Kurtosis	1.46±2.59	1.50±2.33	0.926
1st percentile	34.75±25.37	5.55±6.94	<0.001
10th percentile	50.34±30.05	13.71±13.26	<0.001
50th percentile	75.18±33.12	35.93±20.08	<0.001
90th percentile	103.36±34.30	64.95±22.52	<0.001
99th percentile	135.49±36.23	94.64±28.10	<0.001

Note: *Quantitative data are presented as mean values ± standard deviations.

Table 4 ROC Analysis of Mean, Nth Percentiles for Distinguishing TN-IDC from FA

Parameters	Sensitivity,%	Specificity,%	PPV,%	NPV,%	AUC (95% CI)	Cutoff	Youden Index
Mean	94.55	64.91	72.2	92.5	0.837 (0.756–0.900)	≤62.93	0.5946
1st percentile	100	68.42	75.3	100.0	0.841 (0.760–0.904)	≤22	0.6842
10th percentile	100	66.67	74.3	100.0	0.848 (0.768-0.909)	≤41	0.6667
50th percentile	94.55	64.91	72.2	92.5	0.834 (0.752–0.897)	≤63	0.5946
90th percentile	89.09	63.16	70.0	85.7	0.817 (0.733–0.884)	≤93.5	0.5225
99th percentile	92.73	56.14	67.1	88.9	0.807 (0.721–0.875)	≤133.5	0.4887

Abbreviations: CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value.

Figure 4 Receiver operating characteristic curves for mean, nth percentiles in distinguishing TN-IDC from FA.