Diagnostic value of virtual touch tissue quantification for breast lesions with different size

The value of automated breast volume scanner combined with virtual touch tissue quantification in the differential diagnosis of benign and malignant breast lesions: A comparative study with mammography

This study aimed to evaluate the diagnostic value of automated breast volume scanner (ABVS) combined with virtual touch tissue quantification (VTQ) in the differential diagnosis of breast lesions.In this retrospective study, 183 patients (mean age, 49.8 ± 8.2 years) with 218 breast lesions underwent ABVS, VTQ, and mammography (MG). All lesions were confirmed by postoperative histopathology. A logistic regression model was constructed to generate a receiver operating characteristic (ROC) curve, calculate the area under the ROC curve (AUC), and compare and evaluate the diagnostic performance of ABVS, VTQ, MG, and ABVS combined with VTQ (ABVS-VTQ).The sensitivity, specificity, and accuracy of ABVS, VTQ, MG, and ABVS-VTQ in diagnosing breast lesions were 94.01% (110/117), 96.03% (97/101), and 94.95% (207/218); 80.34% (94/117), 94.05% (95/101), and 86.69% (189/218); 70.08% (82/117), 68.31% (69/101), and 69.26% (151/218); and 96.58% (113/117), 96.03% (97/101), and 96.33% (210/218), respectively. The AUC of ABVS-VTQ was higher than that of the other examinations alone. The detection rate of ABVS (100%, 218/218) was higher than that of MG (78.89%, 172/218), and the difference was statistically significant (χ2 = 51.426, P < .001).The combined application of ABVS and VTQ can improve the accuracy and specificity of the diagnosis and is a promising ultrasound method for the differential diagnosis of breast lesions.

Comparative Diagnostic Accuracy of Contrast-Enhanced Ultrasound and Shear Wave Elastography in Differentiating Benign and Malignant Lesions: A Network Meta-Analysis

Background: We performed a network meta-analysis to compare the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) and shear wave elastography (SWE) in differentiating benign and malignant lesions in different body sites.

Methods: A computerized literature search of Medline, Embase, SCOPUS, and Web of Science was performed using relevant keywords. Following data extraction, we calculated sensitivity, specificity, positive likelihood ratio (LR), negative LR, and diagnostic odds ratio (DOR) for CEUS, and SWE compared to histopathology as a reference standard. Statistical analyses were conducted by MetaDiSc (version 1.4) and R software (version 3.4.3).

Results: One hundred and fourteen studies (15,926 patients) were pooled in the final analyses. Network meta-analysis showed that CEUS had significantly higher DOR than SWE (DOR = 27.14, 95%CI [2.30, 51.97]) in breast cancer detection. However, there were no significant differences between CEUS and SWE in hepatic (DOR = −6.67, 95%CI [−15.08, 1.74]) and thyroid cancer detection (DOR = 3.79, 95%CI [−3.10, 10.68]). Interestingly, ranking analysis showed that CEUS achieved higher DOR in detecting breast and thyroid cancer, while SWE achieved higher DOR in detecting hepatic cancer. The overall DOR for CEUS in detecting renal cancer was 53.44, 95%CI [29.89, 95.56] with an AUROC of 0.95, while the overall DOR for SWE in detecting prostate cancer was 25.35, 95%CI [7.15, 89.89] with an AUROC of 0.89.

Conclusion: Both diagnostic tests showed relatively high sensitivity and specificity in detecting malignant tumors in different organs. Network meta-analysis showed that CEUS had higher diagnostic accuracy than SWE in detecting breast and thyroid cancer, while SWE had higher accuracy in detecting hepatic cancer. However, the results were not statistically significant in hepatic and thyroid malignancies. Further head-to-head comparisons are needed to confirm the optimal imaging technique to differentiate each cancer type.

Complex cystic and solid breast lesions: Diagnostic performance of conventional ultrasound, strain imaging and point shear wave speed measurement

OBJECTIVE

To assess the performance of conventional high frequency ultrasound (US) and US elastography in diagnosis of complex cystic and solid breast lesions.

METHODS

Ninety three lesions in 93 patients underwent conventional US and US elastography, including strain elastography, acoustic radiation force impulse (ARFI) imaging, and point shear wave speed (SWS) measurement.

RESULTS

Pathological examination revealed 31 (33.3%) of the 93 lesions were malignant and the remaining 62 (66.7%) were benign. Multivariate analysis showed that elder patient (OR: 25.301), internal vascularity (OR: 4.518), and not circumscribed margin (OR: 3.813) were independent predictors for malignancy, while predominately cystic lesions (OR: 0.178) was a predictor for benign lesions (all p < 0.05). Invalid SWS measurement was occurred in 19 of 31 (61.3%) malignant lesions and 16 of 62 (25.8%) benign lesions, respectively (p < 0.05). The mean SWS value for malignant lesions was significantly lower than that for benign ones, being 1.60±0.63 m/s (range, 0.68-2.70 m/s) versus 2.33±0.77 m/s (range, 0.67-3.97 m/s) (p < 0.05). Areas under the ROC curve (Azs) for Breast Imaging Reporting and Data System (BI-RADS) assessment, strain elasticity score, ARFI imaging and valid point SWS measurement were 0.844, 0.734, 0.763 and 0.778,respectively.

CONCLUSIONS

US BI-RADS category, strain elastography score, ARFI imaging patterns and point SWS measurement are useful for malignancy prediction of complex cystic and solid breast lesions. The result that SWS for malignant lesions is lower than benign one should be carefully interpreted since invalid SWS measurement is excluded for analysis. The true stiffness of malignant cystic and solid lesions should be further evaluated with a new generation of two-dimensional SWS imaging.

Value of shear wave elastography in discriminating malignant and benign breast lesions: A meta-analysis

The analysis was aimed to evaluate the diagnostic accuracy of shear wave elastography (SWE) for malignant breast lesions through a meta-analysis.Related articles were searched from Pubmed, Embase, and Cochrane library. Overall sensitivity and specificity were analyzed with DerSimonian and Laird random effects model. Area under curve with corresponding 95% confidence interval (were calculated to evaluate the diagnostic accuracy of SWE. Sensitivity and publication bias were assessed as well.A total of 25 articles including 4128 patients and 4546 breast lesions were included in the pooled analysis. In the subgroup analysis, diagnostic sensitivity and specificity of SWE in Asian population were 0.84 (0.79-0.88) and 0.87 (0.84-0.90), respectively, whereas they were 0.92 (0.86-0.96) and 0.89 (0.84-0.92) in Caucasian population. The diagnostic accuracy of SWE was a little higher for Caucasians than for Asians (0.95 vs. 0.92). The diagnostic sensitivity and specificity of virtual touch tissue quantification were 0.85 (0.77-0.91) and 0.93 (0.88-0.96), respectively. It showed a little higher value in specificity and summary ROC curve than SWE (0.93 vs. 0.87; 0.95 vs. 0.93). In addition, maximum stiffness exhibited higher detection sensitivity than that of mean stiffness (0.91 vs. 0.85).SWE serves as an accurate diagnostic technology for discriminating between malignant and benign breast lesions.

Benign and malignant breast lesions identification through the values derived from shear wave elastography: evidence for the meta-analysis

Objective

The analysis was aimed to evaluate the diagnostic accuracy of shear wave elastography (SWE) for malignant breast lesions through a meta-analysis.

Materials and Methods

Related articles were searched in databases of Pubmed, Embase and Cochrane library. Overall sensitivity and specificity were analyzed with DerSimonian and Laird random effects model. Area under curve (AUC) with corresponding 95% confidence interval were also analyzed to evaluate the diagnostic accuracy of SWE. P value < 0.05 predicted the significant heterogeneity between study. Sensitivity and publication bias were assessed as well.

Results

According to the inclusion criteria, 25 articles were selected. In the subgroup analysis, diagnostic sensitivity and specificity of SWE in Asian population were 0.84 (0.79-0.88) and 0.87 (0.84-0.90), respectively, while they were 0.92 (0.86-0.96) and 0.89 (0.84-0.92) in Caucasian population. The diagnostic accuracy of SWE was a little higher for Caucasians than for Asians (0.95 vs. 0.92). The diagnostic sensitivity and specificity of virtual touch tissue quantification (VTTQ) were 0.85 (0.77-0.91) and 0.93 (0.88-0.96), respectively. It showed a little higher value in specificity and summary receiver operating curve (sROC) than that of SWE (0.93 vs. 0.87; 0.95 vs. 0.93). In addition, maximum stiffness exhibited higher detection sensitivity than that of mean stiffness (0.91 vs. 0.85).

Conclusions

SWE serves as an accurate diagnostic technology for discriminating malignant and benign breast lesions.

Combination of conventional ultrasonography and virtual touch tissue imaging quantification for differential diagnosis of breast lesions smaller than 10 mm

OBJECTIVE

To determine the value of combining conventional ultrasonography with virtual touch tissue imaging quantification (VTIQ) for differential diagnosis of breast lesions smaller than 10 mm.

METHODS

A total of 98 breast lesions smaller than 10 mm were examined by conventional ultrasound and VTIQ using a Siemens ACUSON S3000 ultrasound machine. Pathologic diagnosis was established after surgery or fine needle biopsy.

RESULTS

Malignant lesions were characterized by taller-than-wide shape, poorly circumscribed margin, and marked hypoechogenicity. The mean VTIQ shear wave velocity (SWV) value of malignant lesions was 4.88±1.87 m/s (range, 1.75-9.34 m/s), significantly higher than that of benign lesions (2.68±1.02 m/s; range, 1.18-4.67 m/s). The optimal cutoff SWV value was 3.27 m/s, with sensitivity, specificity, diagnostic accuracy, positive predictive value (PPV), and negative predictive value (NPV) of 86.20%, 95.65%, 92.86%, 89.29%, and 94.29%, respectively. The combination of SWV >3.27 m/s plus the US feature of poorly circumscribed margin had the highest sensitivity (93.33%) and specificity (100%) for diagnosis of malignant breast lesions.

CONCLUSION

Features such as taller-than-wide shape, poorly circumscribed margin, and marked hypoechogenicity on conventional US, and SWV >3.27 m/s on VTIQ, are indicators of malignancy in breast lesions with diameter <10 mm. The combination of poorly circumscribed margin and SWV >3.27 m/s provides the highest specificity and diagnostic accuracy.

Ultrasonography methods for predicting malignancy in canine mammary tumors

The aim of this study was to evaluate and compare the efficacy of B-mode, Doppler, contrast-enhanced ultrasonography (CEUS), and Acoustic Radiation Force Impulse (ARFI) elastography in predicting malignancy in canine mammary masses. This was a prospective cohort study from 2014 to 2016, which included 153 bitches with one or more mammary masses. A total of 300 masses were evaluated by ultrasonography (B-mode, Doppler, CEUS, and ARFI) and subsequently classified as benign or malignant by histopathology. Each ultrasound parameters studied were compared between benign and malignant masses by Chi-square or Student tests and differences were considered significant when P < 0.01. For the variables that proved significant differences were estimated the cut-off point, sensitivity, specificity, accuracy, and area under curve (AUC) by receiver-operating characteristic curve (ROC) analysis in a logistic regression model using histopathological classification as reference, to assess and compare diagnostic performance of each technique. Out of 300 mammary masses evaluated 246 were classified as malignant and 54 as benign. B-mode measurements showed sensitivity 67.9%, and specificity 67.6% as malignancy predictors on canine mammary masses; Doppler indexes systolic (>21.2 m/s) and diastolic velocity (>4.8 m/s) sensitivity 79.2% and specificity 70.8%; CEUS wash-out time (<80.5 s) sensitivity 80.2% and specificity 16.7%; and ARFI elastography shear velocity (SWV > 2.57 m/s) sensitivity 94.7% and specificity 97.2% In conclusion B-mode and Doppler ultrasound evaluations may assist in malignancy prediction of canine mammary masses with moderate sensitivity and specificity, already the SWV was an great accurate predictor. Therefore, ARFI elastography exam inclusion in veterinary clinic oncology and research is highly recommended, since it allows fast, non-invasive, and complication-free malignancy prediction of canine mammary masses.

Diagnostic features of quantitative comb-push shear elastography for breast lesion differentiation

BACKGROUND

Lesion stiffness measured by shear wave elastography has shown to effectively separate benign from malignant breast masses. The aim of this study was to evaluate different aspects of Comb-push Ultrasound Shear Elastography (CUSE) performance in differentiating breast masses.

METHODS

With written signed informed consent, this HIPAA- compliant, IRB approved prospective study included patients from April 2014 through August 2016 with breast masses identified on conventional imaging. Data from 223 patients (19-85 years, mean 59.93±14.96 years) with 227 suspicious breast masses identifiable by ultrasound (mean size 1.83±2.45cm) were analyzed. CUSE was performed on all patients. Three regions of interest (ROI), 3 mm in diameter each, were selected inside the lesion on the B-mode ultrasound which also appeared in the corresponding shear wave map. Lesion elasticity values were measured in terms of the Young's modulus. In correlation to pathology results, statistical analyses were performed.

RESULTS

Pathology revealed 108 lesions as malignant and 115 lesions as benign. Additionally, 4 lesions (BI-RADS 2 and 3) were considered benign and were not biopsied. Average lesion stiffness measured by CUSE resulted in 84.26% sensitivity (91 of 108), 89.92% specificity (107 of 119), 85.6% positive predictive value, 89% negative predictive value and 0.91 area under the curve (P<0.0001). Stiffness maps showed spatial continuity such that maximum and average elasticity did not have significantly different results (P > 0.21).

CONCLUSION

CUSE was able to distinguish between benign and malignant breast masses with high sensitivity and specificity. Continuity of stiffness maps allowed for choosing multiple quantification ROIs which covered large areas of lesions and resulted in similar diagnostic performance based on average and maximum elasticity. The overall results of this study, highlights the clinical value of CUSE in differentiation of breast masses based on their stiffness.

Comparison of Virtual Touch Tissue Quantification and Virtual Touch Tissue Imaging Quantification for diagnosis of solid breast tumors of different sizes

BACKGROUND

Acoustic radiation force impulse imaging (ARFI) with Virtual Touch Tissue Quantification (VTQ) or Virtual Touch Tissue Imaging Quantification (VTIQ) measures shear wave velocity (SWV), which is proportional to tissue stiffness, a diagnostic parameter for malignancy.

OBJECTIVE

To compare the performance of VTQ and VTIQ in diagnosing solid breast tumors.

METHODS

Conventional ultrasound, VTQ and VTIQ were used to examine 246 solid breast tumors from 230 patients. Tumors were grouped according to size: <10 mm, 10-20 mm, >20 mm. Pathological diagnoses were via histological examination of biopsies. ROC curves were used to assess diagnostic performance and optimal cut-off points for VTQ and VTIQ.

RESULTS

For all sizes, SWVVTQ and SWVVTIQ were higher for malignant versus benign tumors (P < 0.05). SWVVTQ and SWVVTIQ were both higher for tumors≥10 mm (P < 0.05). Areas under the ROC curves (diagnostic performance index; 0.860-0.952) did not differ significantly between VTQ and VTIQ. Optimal cut-off values for SWVVTQ and SWVVTIQ were higher for tumors≥10 mm.

CONCLUSION

The diagnostic performance of VTQ and VTIQ was moderate to good for solid breast tumors. Although both methods have higher sensitivities in tumors≥10 mm, their overall diagnostic performance was similar for all sizes.

A novel two-dimensional quantitative shear wave elastography to make differential diagnosis of breast lesions: Comprehensive evaluation and influencing factors

BACKGROUND

Virtual touch imaging quantification (VTIQ), a form of shear wave elastography, may help in the diagnosis of breast lesions.

OBJECTIVE

We aimed to evaluate the diagnostic performance of combined VTIQ and conventional ultrasound (US), and assess the factors influencing VTIQ measurement.

METHODS

From September 2014 to December 2014, 162 patients with breast lesions were examined by US and VTIQ to assess shear wave speed (SWS) and morphological characteristics (lesion shape, orientation, margin and echo pattern). The sensitivity, specificity and accuracy of VTIQ, US and VTIQ+US for the diagnosis of breast lesions was evaluated in comparison to pathological results. Factors influencing deviations in SWS measurements were assessed by logistic regression.

RESULTS

The SWS cut-off between malignant and benign lesions was 3.73 m/s. The sensitivity, specificity and accuracy were: 98.07%, 55.96%, and 69.57% for US; 76.92%, 78.89% and 78.26% for VTIQ; and 98.07%, 84.40% and 88.82% for US+VTIQ. The two factors that influenced the SWS results were the lesion margin (odds ratio [OR], 16.363; 95% confidence interval [CI], 3.220-29.020) and vascularity (OR, 6.712; 95% CI, 1.358-9.072).

CONCLUSIONS

The lesion margin and vascularity could affect the measurement of SWS as well as the experience of examiner. However, VTIQ is still a reliable method that provides valuable information in the differential diagnosis of breast lesions, and may reduce unnecessary biopsies.

Diagnostic Value of ARFI (Acoustic Radiation Force Impulse) in Differentiating Benign From Malignant Breast Lesions

RATIONALE AND OBJECTIVES

The aim of this study was to correlate acoustic radiation force impulse (ARFI) imaging velocities with the pathology results and to evaluate the ability of ARFI in distinguishing benign from malignant breast lesions.

MATERIALS AND METHODS

B-mode ultrasonography (US) and ARFI were performed in patients with previously diagnosed and selected breast lesions for biopsy. Shear wave velocity (SWV) was measured inside lesions and in the surrounding parenchyma (m/s). SWV measurements as well as lesion-to-parenchyma ratio (LPR) were compared between benign and malignant lesions, and receiver operating characteristic (ROC) curves were plotted. Two blinded readers independently classified the lesions as benign or malignant in two separate reading sessions, one using B-mode US alone and the other using a combined set of B-mode US and ARFI.

RESULTS

Eighty-one patients with a total of 92 breast lesions were included (57 benign and 35 malignant nodules). SWV inside lesions were significantly higher for malignant neoplasms compared to benign (medians of 9.1 m/s vs 3.5 m/s; P < 0.001). LPR was also significantly higher for malignant lesions (3.0 vs 1.4; P < 0.001). Parenchyma SWV had no differences between groups (P = 0.071). ROC curves showed a significant discriminative power for lesion SWV (area under the curve [AUC] = 0.980; P < 0.001) and LPR (AUC = 0.954; P < 0.001). For lesion measures, a cutoff of 6.593 m/s was obtained, with sensitivity and specificity of 88.6% and 96.5%, respectively.

CONCLUSIONS

ARFI provides quantitative elasticity measurements, adding valuable complementary information to B-mode ultrasound, that can potentially help in breast lesion characterization and assisting the decision for biopsy recommendations.

Breast Lesions: Quantitative Diagnosis Using Ultrasound Shear Wave Elastography-A Systematic Review and Meta--Analysis

The aim of this meta-analysis was to estimate the diagnostic performance of shear wave elastography (SWE) in differentiating malignant from benign breast lesions. A literature search of PubMed, Web of Science and Scopus up to November 2014 was conducted. A summary receiver operating characteristic curve was constructed, and pooled weighted estimates of sensitivity and specificity were calculated using a bivariate mixed-effects regression model. Thirty-three studies, which included a total of 5838 lesions (2093 malignant, 3745 benign) from 5397 patients, were finally analyzed. Summary sensitivity and specificity were 0.886 (95% confidence interval [CI], 0.858-0.909) and 0.866 (95% CI, 0.833-0.894), respectively. The pooled diagnostic odds ratio was 50.410 (95% CI, 34.972-72.664). And the area under the receiver operating characteristic curve of SWE was 0.94 (95% CI, 0.91-0.96). No publication bias existed among these studies (p = 0.245). In the subgroup analysis, sensitivity and specificity were 0.862 (95% CI, 0.811-0.901) and 0.875 (95% CI, 0.793-0.928) among 1552 lesions from 1429 patients in the 12 studies using acoustic radiation force impulse imaging and 0.897 (95% CI, 0.863-0.923) and 0.863 (95% CI, 0.831-0.889) among another 4436 lesions from 4097 patients in the 21 studies using supersonic shear imaging. When analysis confined to 9 studies evaluated the diagnostic performance of combination SWE and conventional ultrasound, the area under the curve was 0.96 (95% CI, 0.94-0.97), yielding a sensitivity of 0.971 (95% CI, 0.941-0.986) and specificity of 0.801 (95% CI, 0.733-0.856). SWE seems to be a good quantitative method for differentiating breast lesions, with promise for integration into routine imaging protocols.

Noninvasive Evaluation of Benign and Malignant Superficial Lymph Nodes by Virtual Touch Tissue Quantification: A Pilot Study

OBJECTIVES

The purpose of this study was to investigate the value of Virtual Touch tissue quantification (Siemens Medical Solutions, Erlangen, Germany) for differentiation of benign and malignant superficial lymph node lesions.

METHODS

Shear wave velocity (SWV) values were analyzed in 113 patients, who also had diagnoses by pathologic examination. The diagnostic performance of the SWV was evaluated by sensitivity and specificity at the optimum cutoff value and the area under the receiver operating characteristic curve (AUROC).

RESULTS

A total of 60 benign lesions (32 reactive hyperplasia and 28 tuberculosis) and 53 malignant lesions (27 lymphomas and 26 metastatic carcinomas) were studied. The SWV was significantly different between benign (mean ± SD, 3.137 ± 0.857 m/s) and malignant (7.042 ± 1.427 m/s) lesions (P< .001) and yielded sensitivity of 92.5% (95% confidence interval [CI], 81.8%-97.9%) and specificity of 96.7% (95% CI, 88.5%-99.6%) at an optimum cutoff value of 4.645 m/s. The AUROC was 0.973 (95% CI, 0.924-0.994). To separate reactive hyperplasia from tuberculosis within benign lesions, a cutoff value of 2.978 m/s provided sensitivity of 92.9% (95% CI, 76.5%-99.1%) and a specificity of 100% (95% CI, 89.1%-100%), with an AUROC of 0.989 (95% CI, 0.920-1.000). To separate lymphoma from metastatic carcinoma within malignant lesions, a cutoff value of 7.302 m/s provided sensitivity of 88.5% (95% CI, 69.8%-97.6%) and specificity of 81.5% (95% CI, 61.9%-93.7%), with an AUROC of 0.906 (95% CI, 0.764-0.969).

CONCLUSIONS

Virtual Touch tissue quantification provides a promising noninvasive strategy for differentiation of benign and malignant superficial lymph node lesions.

Elastography by acoustic radiation force impulse technology for differentiation of benign and malignant breast lesions: a meta-analysis

PURPOSE

To perform a meta-analysis assessing the ability of elastography by acoustic radiation force impulse (ARFI) technology to differentiate benign and malignant breast lesions.

METHODS

PubMed, the Cochrane Library, and the Web of Knowledge before September 24, 2014 were searched. Published studies that evaluated the diagnostic performance of ARFI for characterization of focal breast lesions were included.

RESULTS

A total of fifteen studies, including 1720 patients with 1873 breast lesions (743 cancers, 1130 benign lesions), was analyzed. Among the included studies, virtual touch tissue imaging (VTI) was used in six studies, virtual touch tissue quantification (VTQ) in eight, combined VTI and VTQ in four, and virtual touch tissue imaging quantification (VTIQ) in three. Summary sensitivity and summary specificity for distinguishing malignant from benign breast lesions were 0.913 [95% confidence interval (CI), 0.779-0.969] and 0.871 (95% CI 0.773-0.930) for VTI, 0.849 (95% CI 0.805-0.884) and 0.889 (95% CI 0.771-0.950) for VTQ, and 0.935 (95% CI 0.892-0.961) and 0.881 (95% CI 0.818-0.924) for combined VTI and VTQ, respectively. The area under summary receiver operating characteristic (sROC) curve of VTI, VTQ, and combined VTI and VTQ were 0.95, 0.88, and 0.96, respectively. Significant publication bias was found only in the VTQ assessment (p = 0.025). The obtained sensitivity of VTIQ ranged from 80.4 to 90.3%, while the specificity ranged from 73.0 to 93.0%. The summary diagnostic value of VTIQ could not be evaluated due to insufficient data.

CONCLUSION

Elastography by ARFI technology could be used as a good identification tool for differentiating benign and malignant breast lesions.

Effect of Calcifications on Breast Ultrasound Shear Wave Elastography: An Investigational Study

Purpose

To investigate the effects of macrocalcifications and clustered microcalcifications associated with benign breast masses on shear wave elastography (SWE).

Methods

SuperSonic Imagine (SSI) and comb-push ultrasound shear elastography (CUSE) were performed on three sets of phantoms to investigate how calcifications of different sizes and distributions influence measured elasticity. To demonstrate the effect in vivo, three female patients with benign breast masses associated with mammographically-identified calcifications were evaluated by CUSE.

Results

Apparent maximum elasticity (E_max) estimates resulting from individual macrocalcifications (with diameters of 2mm, 3mm, 5mm, 6mm, 9mm, 11mm, and 15mm) showed values over 50 kPa for all cases, which represents more than 100% increase over background (~21kPa). We considered a 2cm-diameter circular region of interest for all phantom experiments. Mean elasticity (E_mean) values varied from 26 kPa to 73 kPa, depending on the macrocalcification size. Highly dense clusters of microcalcifications showed higher E_max values than clusters of microcalcification with low concentrations, but the difference in E_mean values was not significant.

Conclusions

Our results demonstrate that the presence of large isolated macrocalcifications and highly concentrated clusters of microcalcifications can introduce areas with apparent high elasticity in SWE. Considering that benign breast masses normally have significantly lower elasticity values than malignant tumors, such areas with high elasticity appearing due to presence of calcification in benign breast masses may lead to misdiagnosis.

Update on Breast Cancer Detection Using Comb-Push Ultrasound Shear Elastography

In this work, tissue stiffness estimates are used to differentiate between benign and malignant breast masses in a group of pre-biopsy patients. The rationale is that breast masses are often stiffer than healthy tissue; furthermore, malignant masses are stiffer than benign masses. The comb-push ultrasound shear elastography (CUSE) method is used to noninvasively assess a tissue's mechanical properties. CUSE utilizes a sequence of simultaneous multiple laterally spaced acoustic radiation force (ARF) excitations and detection to reconstruct the region of interest (ROI) shear wave speed map, from which a tissue stiffness property can be quantified. In this study, the tissue stiffnesses of 73 breast masses were interrogated. The mean shear wave speeds for benign masses (3.42 ± 1.32 m/s) were lower than malignant breast masses (6.04 ± 1.25 m/s). These speed values correspond to higher stiffness in malignant breast masses (114.9 ± 40.6 kPa) than benign masses (39.4 ± 28.1 kPa and p <; 0.001), when tissue elasticity is quantified by Young's modulus. A Young's modulus >83 kPa is established as a cut-off value for differentiating between malignant and benign suspicious breast masses, with a receiver operating characteristic curve (ROC) of 89.19% sensitivity, 88.69% specificity, and 0.911 for the area under the curve (AUC).

Diagnostic value of virtual touch tissue imaging quantification for benign and malignant breast lesions with different sizes

The study was to explore diagnostic value of the virtual touch tissue imaging quantification (VTIQ) in distinguishing benign and malignant breast lesions of variable sizes. We performed conventional ultrasound and VTIQ in 139 breast lesions. The lesions were categorized into three groups according to size (group 1, ≤ 10 mm; group 2, 10-20 mm; and group 3, > 20 mm), and their mean, min, and max shear wave velocities (SWVs) were measured. Diagnoses were confirmed by pathological examination after surgery or needle biopsy. Receiver-operating characteristic curves (ROC) were constructed to determine the optimum cut-off values, calculate the area under curve (AUC), the sensitivity, specificity and accuracy for each velocity. For all groups, the mean, min, and max SWVs of malignant lesions were significantly higher than those of benign lesions (P < 0.05). The cut-off values of mean, min, and max SWVs were not significantly different among the three groups. In addition, the diagnostic performance of mean, min, and max SWV values is analogous, regardless of lesion size. In conclusion, VTIQ is a strong complement to conventional ultrasound, which is a promising method in the differential diagnosis of the breast lesions with different sizes. Further studies validate our results as well as reduce the number of unnecessary biopsies, regardless of size is warranted.

A novel two-dimensional quantitative shear wave elastography for differentiating malignant from benign breast lesions

OBJECTIVE

The purpose of this study was to evaluate the diagnostic performance of a novel quantitative shear wave elastography (SWE) of virtual touch tissue imaging quantification (VTIQ) in diagnosis of breast lesions.

METHODS

The conventional ultrasound (US) and VTIQ images of 133 pathologically proven breast lesions in 98 patients were assessed. The breast lesions were classified by US breast imaging reporting and data system (BI-RADS) category. The maximum, minimum, mean and median shear wave velocity (SWV) values on VTIQ in the lesions were obtained. The area under the receiver operating curve (AUC) was computed.

RESULTS

Twenty-six of 133 lesions were malignant and 107 were benign. The sensitivity and specificity for US BI-RADS assessment were 96.2% and 62.6% respectively. The SWVs in malignant lesions were all significantly higher than those in benign ones (all P < 0.001). The AUC for mean SWV value was slightly higher than AUC for maximum, minimum and median SWV values, whereas no significant differences among them were found (all P > 0.05). The cut-off value of mean SWV was 3.68 m/s, with associated sensitivity and specificity of 93.3% and 79.4% respectively.

CONCLUSION

The novel quantitative SWE of VTIQ is helpful in differentiating breast lesions. Adding the quantitative SWE of VTIQ to the US BI-RADS assessment improves the specificity in diagnosing breast lesions without loss of sensitivity.

Comb-push ultrasound shear elastography of breast masses: initial results show promise

Purpose or Objective

To evaluate the performance of Comb-push Ultrasound Shear Elastography (CUSE) for classification of breast masses.

Materials and Methods

CUSE is an ultrasound-based quantitative two-dimensional shear wave elasticity imaging technique, which utilizes multiple laterally distributed acoustic radiation force (ARF) beams to simultaneously excite the tissue and induce shear waves. Female patients who were categorized as having suspicious breast masses underwent CUSE evaluations prior to biopsy. An elasticity estimate within the breast mass was obtained from the CUSE shear wave speed map. Elasticity estimates of various types of benign and malignant masses were compared with biopsy results.

Results

Fifty-four female patients with suspicious breast masses from our ongoing study are presented. Our cohort included 31 malignant and 23 benign breast masses. Our results indicate that the mean shear wave speed was significantly higher in malignant masses (6 ± 1.58 m/s) in comparison to benign masses (3.65 ± 1.36 m/s). Therefore, the stiffness of the mass quantified by the Young’s modulus is significantly higher in malignant masses. According to the receiver operating characteristic curve (ROC), the optimal cut-off value of 83 kPa yields 87.10% sensitivity, 82.61% specificity, and 0.88 for the area under the curve (AUC).

Conclusion

CUSE has the potential for clinical utility as a quantitative diagnostic imaging tool adjunct to B-mode ultrasound for differentiation of malignant and benign breast masses.

Breast vibro-acoustography: initial experience in benign lesions

Background

Vibro-acoustography (VA) is a newly developed imaging technology that is based on low-frequency vibrations induced in the object by the radiation force of ultrasound. VA is sensitive to the dynamic characteristics of tissue. Here, we evaluate the performance of VA in identifying benign lesions and compare the results to those of mammography.

Methods

An integrated mammography-VA system designed for in vivo breast imaging was tested on a group of female volunteers, age ≥ 18 years, with suspected breast lesions based on clinical examination. A set of VA scans was acquired after each corresponding mammography. Most lesions were classified as benign based on their histological results. However, in 4 cases, initial diagnosis based on clinical imaging determined that the lesions were cysts. These cysts were aspirated with needle aspiration and disappeared completely under direct ultrasound visualization. Therefore, no biopsies were performed on these cases and lesions were classified as benign based on clinical findings per clinical standards. To define the VA characteristics of benign breast masses, we adopted the features that are normally attributed to such masses in mammography. In a blinded assessment, three radiologists evaluated the VA images independently. The diagnostic accuracy of VA for detection of benign lesions was assessed by comparing the reviewers’ evaluations with clinical data.

Results

Out of a total 29 benign lesions in the group, the reviewers were able to locate all lesions on VA images and mammography, 100% with (95% confidence interval (CI): 88% to 100%). Two reviewers were also able to correctly classify 83% (95% CI: 65% to 92%), and the third reviewer 86% (95% CI: 65% to 95%) of lesions, as benign on VA images and 86% (95% CI: 69% to 95%) on mammography.

Conclusions

The results suggest that the mammographic characteristics of benign lesion may also be used to identify such lesions in VA. Furthermore, the results show the ability of VA to detect benign breast abnormalities with a performance comparable to mammography. Therefore, the VA technology has the potential to be utilized as a complementary tool for breast imaging applications. Additional studies are needed to compare the capabilities of VA and traditional ultrasound imaging.

Relationship between parameters from virtual touch tissue quantification (VTQ) imaging with clinicopathologic prognostic factors in women with invasive ductal breast cancer

OBJECTIVES

To investigate the association of shear wave velocity (SWV) and its ratio (SWV ratio) using virtual touch tissue quantification (VTQ) imaging with clinicopathologic prognostic factors in women with invasive ductal breast cancer.

METHODS

138 consecutive women with invasive ductal breast cancer, who were diagnosed by pathological examination, were recruited between September 2011 and October 2013. Clinicopathologic findings were investigated in each participant, including age, invasive size, lymph node status, histological grade, estrogen receptor (ER) expression, progesterone receptor (PR) expression and human epidermal growth factor receptor 2 (C-erbB-2) expression. SWV and its ratio (breast mass/adjacent breast tissue) were measured by the VTQ imaging, and univariate analysis and multivariate regression analyses were applied to investigate their relationship with all clinicopathologic abnormalities.

RESULTS

In univariate analyses, large mass size (P < 0.001), lymph node involvement (P < 0.001), High histological grade (P = 0.001) and C-erbB-2 expression (P = 0.029) were significantly associated with SWV, whereas large invasive size (P < 0.001), lymph node involvement (P = 0.001) and high histological grade (P = 0.007) were significantly related to SWV ratio. Multiple linear regression indicated that invasive size was the strongest pathologic determinant of SWV and its ratio (P < 0001).

CONCLUSION

SWV and its ratio by the VTQ imagining were significantly associated with clinicopathologic abnormalities, and may therefore provide prognostic information in patients with invasive ductal breast cancer.