Use of shear wave elastography to differentiate benign and malignant breast lesions

PURPOSE

We aimed to determine the correlations between the elasticity values of solid breast masses and histopathological findings to define cutoff elasticity values differentiating malignant from benign lesions.

MATERIALS and METHODS

A total of 115 solid breast lesions of 109 consecutive patients were evaluated prospectively using shear wave elastography (SWE). Two orthogonal elastographic images of each lesion were obtained. Minimum, mean, and maximum elasticity values were calculated in regions of interest placed over the stiffest areas on the two images; we also calculated mass/fat elasticity ratios. Correlation of elastographic measurements with histopathological results were studied.

RESULTS

Eighty-three benign and thirty-two malignant lesions were histopathologically diagnosed. The minimum, mean, and maximum elasticity values, and the mass/fat elasticity ratios of malignant lesions, were significantly higher than those of benign lesions. The cutoff value was 45.7 kPa for mean elasticity (sensitivity, 96%; specificity, 95%), 54.3 kPa for maximum elasticity (sensitivity, 95%; specificity, 94%), 37.1 kPa for minimum elasticity (sensitivity, 96%; specificity, 95%), and 4.6 for the mass/fat elasticity ratio (sensitivity, 97%; specificity, 95%).

CONCLUSION

SWE yields additional valuable quantitative data to ultrasonographic examination on solid breast lesions. SWE may serve as a complementary tool for diagnosis of breast lesions. Long-term clinical studies are required to accurately select lesions requiring biopsy.Breast cancer is associated with high morbidity; ∼1.38 million new cases and 458 000 deaths occur annually worldwide (1). Breast cancer is by far the most common cancer in females of both developed and developing countries, and remains a major public health problem.Annual mammographic screening is valuable for early detection of breast cancer, reducing mortality and morbidity, particularly of patients with tumors in fatty breast tissue (2). Increase in breast tissue density over time is a serious problem; this reduces the diagnostic accuracy of breast cancer, especially in younger females (3). Thus, as the proportion of glandular breast tissue rises, other imaging methods are required (4).Gray-scale ultrasonography is a valuable adjunct to mammography and other breast imaging methods, affording highly sensitive assessment of breast masses and differentiating benign solid breast lesions from those that are malignant (5–7). However, ultrasonography is strongly subjective and poorly specific (8–10).Breast biopsy remains the gold standard for definitive diagnosis of suspicious breast lesions. Although the total number of females referred for interventional diagnostic procedures represents a small percentage of any screened population, the healthcare resources consumed by such females are disproportionately high (11). Further, the pathological result is benign in up to 75% of all cases (11–13). Therefore, a reliable, noninvasive, costeffective method helping to differentiate benign from malignant breast lesions, thus reducing the number of unnecessary interventional diagnostic procedures, would be valuable.Sonoelastography uses ultrasound to assess tissue stiffness (elasticity), which can be described using Young’s modulus: E=σ/ε, where σ is the applied stress and ε the resultant tissue deformation. Two principal sonoelastographic approaches are available; these are static (strain) and transient (vibration; shear wave) elastography. In static elastography, a transducer is used to compress tissue and the resulting strain is presented as a color map of tissue elasticity superimposed on the real-time gray-scale sonogram.Static elastography is associated with significant interobserver variability, and uses elastographic scoring (ES) or strain ratio (SR) measurement as a diagnostic parameter. Both ES and SR are subjective semi-quantitative measures (14, 15). Shear wave elastography (SWE) is a novel technique applicable to soft tissue. In SWE, transverse shear waves spreading laterally from the tissue are tracked, and the speed of propagation calculated. SWE yields real-time quantitative data and is highly reproducible compared to static elastography (16, 17). Reproducibility of the latter technique is considered to be a major problem and may compromise patient outcomes. Thus, further work on the utility of SWE is needed.In the present study we sought to correlate the SWE values of a series of solid breast masses with histopathological findings, and to determine cutoff elasticity values allowing benign and malignant tumors to be distinguished.     

超声弹性成像评分对鉴别乳腺肿瘤良恶性的价值

_目的：分析弹性成像评分与免疫组织化学因子雌激素受体（ER）、孕激素受体（PR）的关系,探讨弹性成像评分对鉴别乳腺肿瘤良恶性的价值。方法：选取乳腺肿瘤患者100例,运用彩色超声弹性成像技术对患者的病灶进行探查,采用免疫组织化学技术对患者新鲜活检组织标本进行处理,记录其 ER 和 PR 值,并进行统计学分析。结果：乳腺肿瘤弹性成像评分与 ER（rs＝0．835,P＝0．000）及 PR（rs＝0．816,P＝0．000）的表达程度均呈正相关。超声弹性成像评分诊断乳腺肿瘤良恶性的总体符合率达到73％,与免疫组织化学方法近似（ER：71％,PR：61％）,差异不具有统计学意义（P＞0．05）。结论：乳腺弹性成像评分与病灶 ER 及 PR 蛋白表达呈正相关,对鉴别乳腺肿瘤良恶性具有重要价值。     

彩色多普勒超声对乳腺良恶性肿块的鉴别诊断价值

目的应用彩色多普勒血流显像（CDFI）观察乳腺肿块的血流特点，评价血流参数（PSV、R0对乳腺良、恶性肿块的鉴别诊断价值。方法运用CDFI检测73例的77个乳腺肿块，并与术后病理对照。对其中超声检测出血流的60个乳腺肿块观察血流特点并进行血流参数测定，比较乳腺良、恶性肿块的差异，同时对RI诊断的敏感性、特异性、阳性预测值、阴性预测值加以分析。结果乳腺恶性肿块的CDFI血流信号较良性肿块明显丰富。恶性肿块的PSV、RI值明显高于良性肿块CP〈O．05），以RI≥0．70诊断乳腺癌敏感性和特异性较高，分别为82．6％和80．95％。结论彩色多普勒血流显像及血流参数测定对乳腺良、恶肿块的鉴别诊断具有重要的参考价值。     

Study of quantitative elastography with supersonic shear imaging in the diagnosis of breast tumours

Purpose

This study was undertaken to evaluate the value of quantitative elastography in the diagnosis of breast tumours.

Materials and methods

Conventional ultrasound (US) and quantitative elastography were performed in 108 women with 114 breast lesions by two experienced radiologists, and pathological results were available in all cases. For each lesion, the maximum, mean, and minimum (min) elasticity and elasticity ratio between lesions and surrounding tissue were measured. The Breast Imaging Reporting and Data System (BI-RADS) categories were assessed with conventional US in all lesions.

Results

Malignant lesions exhibited significantly higher maximum and mean elasticity (111.57±69.29 kPa and 54.49±33.70 kPa) than did benign lesions (59.00±45.3 kPa and 36.64±26.18 kPa) (p<0.01). For maximum elasticity versus BI-RADS, performance results were sensitivity 60.9 % vs. 78.3%, specificity 85.3% vs. 98.5%, positive predictive value (PPV) 73.7% vs. 97.3 %, negative predictive value (NPV) 76.3% vs. 87.0 % and accuracy 75.4% vs. 90.3%. BI-RADS had significantly better accuracy than maximum elasticity (p<0.01). Maximum and mean elasticity of invasive ductal carcinoma (IDC) were significantly higher than those of fibroadenoma (p<0.01), whereas the difference was not statistically significant with fibroadenosis, papilloma and inflammation (p>0.01). Maximum and mean elasticity and elasticity ratio of BI-RADS 5 were all significantly higher than those of BI-RADS 3 (p<0.01). Reliability for maximum and mean elasticity were almost perfect [intraclass correlation coefficients (ICC)=0.87 and 0.79].

Conclusions

Shear-wave elastography gives quantitative elasticity information that could potentially help in breast-lesion characterisation, although it cannot replace conventional BI-RADS in the differentiation of breast lesions.     

剪切波弹性成像在乳腺良恶性肿块鉴别诊断中应用价值

目的探讨剪切波弹性成像在乳腺良恶性肿块鉴别诊断中的应用价值。方法选取自2016年8月至2017年6月于北部战区总医院住院手术或穿刺活检的117例女性患者为研究对象,测定117个乳腺肿块的最大值、标准差,即shell 1 mm最大值、shell 1 mm标准差,shell 2 mm最大值、shell 2 mm标准差,shell 3 mm最大值、shell 3 mm标准差,以及肿块及1 mm"壳"在内的最大值、肿块及1 mm"壳"在内的标准差,肿块及2 mm"壳"在内的最大值、肿块及2 mm"壳"在内的标准差,肿块及3 mm"壳"在内的最大值、肿块及3 mm"壳"在内的标准差。以病理诊断结果为"金标准"绘制受试者工作特征(ROC)曲线,比较得出最有意义的值,并计算诊断临界值。结果通过ROC曲线分析,shell 3 mm最大值曲线下面积最大,为0. 768,敏感性为78. 6%,特异度为64. 0%,杨氏模量值诊断临界值为93. 470 k Pa。肿块周围组织既"壳"的硬度大于肿块的硬度时出现"硬环征","硬环征"曲线下面积为0. 862,敏感性为85. 7%,特异度为86. 7%。结论肿块周围组织既"壳"的厚度为3 mm时,杨氏模量值意义最大。将肿块周围组织既"壳"的厚度为3 mm时杨氏模量值与硬环征结合可增加诊断的准确率。     

Differentiation of benign from malignant solid breast masses: comparison of two-dimensional and three-dimensional shear-wave elastography

Objectives

To prospectively compare the diagnostic performances of two-dimensional (2D) and three-dimensional (3D) shear-wave elastography (SWE) for differentiating benign from malignant breast masses.

Methods

B-mode ultrasound and SWE were performed for 134 consecutive women with 144 breast masses before biopsy. Quantitative elasticity values (maximum and mean elasticity in the stiffest portion of mass, E_max and E_mean; lesion-to-fat elasticity ratio, E_rat) were measured with both 2D and 3D SWE. The area under the receiver operating characteristic curve (AUC), sensitivity and specificity of B-mode, 2D, 3D SWE and combined data of B-mode and SWE were compared.

Results

Sixty-seven of the 144 breast masses (47 %) were malignant. Overall, higher elasticity values of 3D SWE than 2D SWE were noted for both benign and malignant masses. The AUC for 2D and 3D SWE were not significantly different: E_mean, 0.938 vs 0.928; E_max, 0.939 vs 0.930; E_rat, 0.907 vs 0.871. Either 2D or 3D SWE significantly improved the specificity of B-mode ultrasound from 29.9 % (23 of 77) up to 71.4 % (55 of 77) and 63.6 % (49 of 77) without a significant change in sensitivity.

Conclusion

Two-dimensional and 3D SWE performed equally in distinguishing benign from malignant masses and both techniques improved the specificity of B-mode ultrasound.

Key Points

? Shear-wave elastography (SWE) is increasingly used during ultrasound of the breast ? 2D and 3D SWE performed equally in distinguishing benign from malignant masses ? Either SWE method, combined with B-mode, outperformed B-mode ultrasound alone ? Quantitative elasticity was greater for 3D than 2D SWE for all masses     

201Tl imaging for differentiating between malignant and benign neck masses

The aim of this study was to assess the ability of 201Tl scintigraphy to differentiate between malignant and benign neck masses. Fifty-eight patients with neck masses, whose diagnoses were confirmed by histological examination, were examined. The sensitivity, specificity and accuracy of 201Tl scintigraphy were 80%, 96% and 88% respectively; when salivary gland masses were excluded, these values were 87%, 95% and 91% respectively. Our results suggest that 201Tl scintigraphy is highly reliable in determining the malignancy of neck masses, especially when salivary gland masses are excluded.     

Characterization of benign and malignant solid breast masses in harmonic 3D power Doppler imaging

Purpose

The authors assessed the characteristics of benign and malignant solid breast tumors in harmonic three-dimensional (3D) power Doppler imaging and proposed decision models to classify benign and malignant breast tumors.

Materials and methods

A total of 86 malignant and 97 benign harmonic 3D power Doppler US images were analyzed. All the harmonic 3D power Doppler images were obtained using a Voluson730 US system (GE, Zipf, Austria) equipped with a RSP 6-12 transducer and tissue harmonic imaging modalities. Imaging analysis was performed using the Virtual Organ Computer-aided Analysis (VOCAL)-imaging program. Histogram indices, the vascularization index (VI), flow index (FI) and vascularization-flow index (VFI), were calculated for the intra-tumor and for shells with an outside thickness of 3 mm surrounding the breast tumors. The receiver operating characteristic (ROC) curves were calculated to estimate the diagnostic performances.

Results

The results revealed that the choice of decision model comprised the parameters of patient age, intra-tumor VI, and tumor volume to classify benign and malignant breast tumors. The area under the ROC curve (Az) was 0.910, accuracy was 81.4%, and sensitivity and specificity were 81.4% and 81.4%, respectively. The parameter intra-tumor VI was the choice for all of the histogram indices in differentiating between malignant and benign lesions.

Conclusion

The decision model, which was composed of patient age, tumor volume and intra-tumor VI, and a cut-off value for intra-tumor VI at the upper end of patient age and tumor volume, was recommended in clinical application.     

Role of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) in differentiating between benign and malignant breast lesions

Objective

To assess the role of DWI and ADC in differentiating between benign and malignant breast lesions.

Materials and methods

51 patients (age range 24–66 years; mean age 48 years) were included in our study. MRI was done using bilateral fat-suppressed T2- weighted fast spin-echo, STIR, axial T1-weighted fast spin-echo. DWI series were acquired using echo planar imaging pulse sequences incorporated with diffusion gradients and finally dynamic contrast enhancement study was done.

Results

Sixty three lesions were detected in 51 patients included in our study. Twenty one lesions were malignant, three lesions were intermediate and twenty two lesions were fibroadenoma according to the final histopathological study and seventeen lesions were breast cysts. A total of 21 lesions showed lower ADC values than benign lesions and were in the range of 0.76–1.29 × 10⁻³ mm²/s and were diagnosed as malignant breast lesions. The sensitivity and specificity for DWI in the differentiating malignant from benign breast lesions were calculated and showed 95.4% and 97.5%, respectively.

Conclusion

DWI is easy to obtain in short scan time and easy to evaluate, and ADC values can differentiate between benign and malignant breast lesions with high sensitivity and specificity.     

MR diffusion imaging and ADC measurement in solid and cystic mediastinal masses for differentiating benign from malignant lesions

Purpose

The purpose of this study is to evaluate the role of MR diffusion imaging (DWI) and apparent diffusion coefficient (ADC) measurement of solid and cystic mediastinal masses to differentiate benign from malignant lesions.

Qualitative pattern classification of shear wave elastography for breast masses: How it correlates to quantitative measurements

Objective

To determine the correlation of qualitative shear wave elastography (SWE) pattern classification to quantitative SWE measurements and whether it is representative of quantitative SWE values with similar performances.

Methods

From October 2012 to January 2013, 267 breast masses of 236 women (mean age: 45.12 ± 10.54 years, range: 21–88 years) who had undergone ultrasonography (US), SWE, and subsequent biopsy were included. US BI-RADS final assessment and qualitative and quantitative SWE measurements were recorded. Correlation between pattern classification and mean elasticity, maximum elasticity, elasticity ratio and standard deviation were evaluated. Diagnostic performances of grayscale US, SWE parameters, and US combined to SWE values were calculated and compared.

Results

Of the 267 breast masses, 208 (77.9%) were benign and 59 (22.1%) were malignant. Pattern classifications significantly correlated with all quantitative SWE measurements, showing highest correlation with maximum elasticity, r = 0.721 (P < 0.001). Sensitivity was significantly decreased in US combined to SWE measurements to grayscale US: 69.5–89.8% to 100.0%, while specificity was significantly improved: 62.5–81.7% to 13.9% (P < 0.001). Area under the ROC curve (A_z) did not show significant differences between grayscale US to US combined to SWE (P > 0.05).

Conclusion

Pattern classification shows high correlation to maximum stiffness and may be representative of quantitative SWE values. When combined to grayscale US, SWE improves specificity of US.     

The added value of qualitative and quantitative diffusion-weighted magnetic resonance imaging (DW-MRI) in differentiating benign from malignant breast lesions

Objective

To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) with calculation of the apparent diffusion coefficient (ADC) value in characterizing benign and malignant breast lesions.

Three-dimensional shear-wave elastography for differentiating benign and malignant breast lesions: comparison with two-dimensional shear-wave elastography

Objectives

To evaluate the interobserver agreement and the diagnostic performance of 3D shear-wave elastography (SWE) for breast lesions in comparison with 2D SWE.

Methods

A total of 163 breast lesions (malignant 48, benign 115) in 146 women who underwent B-mode ultrasound and SWE before biopsy were included. Two radiologists reviewed six data sets (B-mode, SWE, and a combination of both for 2D and 3D ultrasound). B-mode and SWE features were recorded. BI-RADS category was assigned for B-mode and combined sets. Interobserver variability was assessed using the κ statistic. Diagnostic performance of each data set was evaluated using the area under the ROC curve (AUC).

Results

SWE showed substantial to almost perfect agreement, with E_homo in 2D SWE being higher than in 3D SWE. The AUC of 2D SWE was higher than 3D SWE for all SWE features, significantly so for E_col (0.933 vs. 0.867, P?=?0.002) and E_max (0.961 vs. 0.874, P?=?0.006). After adding SWE to B-mode ultrasound, the AUC in 2D ultrasound increased significantly (0.968 vs. 0.912, P?=?0.008), but 3D ultrasound showed no significant difference (0.966 vs. 0.935; P?=?0.07).

Conclusion

For 3D SWE, interobserver agreement was good, but the diagnostic performance was inferior to 2D SWE even after adding to B-mode ultrasound.

Key Points

? Shear-wave elastography (SWE) provides further diagnostic information during breast ultrasound. ? 3D SWE diagnostic performance is inferior to 2D SWE. ? In 3D SWE, interobserver agreement was good. ? 2D B-mode ultrasound showed significant diagnostic improvement when combined with 2D SWE. ? 3D B-mode ultrasound performance was not significantly improved when combined with 3D SWE.     

Differentiation of benign from malignant solid breast masses: conventional US versus spatial compound imaging

PURPOSE: To compare prospectively the diagnostic performance of radiologists who used conventional ultrasonography (US) with that of radiologists who used spatial compound imaging for the differentiation of benign from malignant solid breast masses. MATERIALS AND METHODS: The study was approved by the institutional review board, and informed consent was obtained. Before excisional or needle biopsy was performed, conventional US and spatial compound images were obtained in 67 patients (age range, 25-67 years; mean age, 45 years) with 75 solid breast masses (21 cancers and 54 benign lesions). Three experienced radiologists who did not perform the examinations independently analyzed US findings and indicated the probability of malignancy. Results were evaluated with kappa statistics and receiver operating characteristic (ROC) analysis. RESULTS: For US findings, the presence of calcifications was the most discordant feature (kappa = 0.372) between conventional US and spatial compound imaging, followed by echotexture (kappa = 0.439), boundary echo (kappa = 0.496), orientation (kappa = 0.518), echogenicity (kappa = 0.523), shape (kappa = 0.526), margin (kappa = 0.569), and posterior acoustic transmission (kappa = 0.669). The area under the ROC curve for conventional US was 0.79 for reader 1, 0.88 for reader 2, and 0.82 for reader 3, and the area under the ROC curve for spatial compound imaging was 0.85 for reader 1, 0.88 for reader 2, and 0.89 for reader 3. The partial area index for conventional US was 0.29 for reader 1, 0.69 for reader 2, and 0.39 for reader 3, and the partial area index for spatial compound imaging was 0.29 for reader 1, 0.65 for reader 2, and 0.39 for reader 3. The difference between the diagnostic performances of the two techniques was not significant (P > .05). CONCLUSION: The performance of the radiologists with respect to the characterization of solid breast masses was not significantly improved with spatial compound imaging.     

Incremental value of real-time ultrasound elastography in differentiating breast masses

Aim of the work

To evaluate the value of real-time ultrasound elastography (RTE) in differentiating benign from malignant breast masses.

Materials and methods

This study included, whether palpable or non-palpable, 145 sonographically proven breast masses in 121 patients, imaged by conventional B-mode US, color-flow Doppler US and RTE with histopathological analysis considered as the golden standard reference.

Results

Lesions were differentiated into benign and malignant by conventional B-mode US (79; 45.5% and 66; 54.5%, respectively), RTE (80; 55.2% and 65; 44.8% respectively), and histopathology (82; 56.6% and 63; 43.4%, respectively). The mean difference in the mass size was significant between B-mode US and RTE in malignant masses (P = 0.002), while not significant among benign masses (P = 0.153). The B-mode US depicted sensitivity of 92.06%, specificity of 90.24%, PPV of 87.88%, NPV of 93.67% and accuracy of 91.03%, while the RTE showed sensitivity of 98.41%, specificity of 96.34%, PPV of 95.38%, NPV of 98.75% and accuracy of 97.24%.

Conclusion

Combined use of RTE can complement conventional B-mode US with improving its diagnostic performance in differentiating breast lesions with subsequent reduction in the rate of unnecessary biopsies in benign lesions.     

剪切波弹性成像对甲状腺良恶性结节的诊断价值

目的:探讨超声剪切波弹性成像(SWE)对甲状腺良恶性结节的诊断价值.方法:收集104例(126个结节)甲状腺结节为研究对象,采用常规超声检查结节的回声、边缘、内部钙化程度、组成及形状;采用CDFI评估结节血流;采用SWE定性和定量评估结节弹性,获取剪切波速度(SWV),并通过ROC曲线计算SWV的最佳临界值.以最大SW...