US of mammographically detected clustered microcalcifications

Normalized Spatial Autocorrelation in Ultrasound B-Mode Imaging for Point-Scatterer Detection

OBJECTIVE

Point-scatterer detection plays a key role in medical ultrasound B-mode imaging. Speckle noise and insufficient spatial resolution are important factors affecting point-scatterer detection. To address this issue, normalized spatial autocorrelation in ultrasound B-mode imaging (NSACB) is proposed.

METHODS

First, the acquired data are pre-processed by adding Gaussian white noise (GWN) with a certain signal-to-Gaussian white noise ratio (SGWNR). Next, normalized spatial autocorrelation is applied to the pre-processed data, and the data are divided into several new signals with different spatial lags. Then, the new signals are performed unsigned delay multiply and sum. Finally, the NSACB beamformed data are bandpass filtered by extracting the frequency component around twice the center frequency. Simulated and in vitro experiments were designed for validation.

RESULTS

Simulations revealed that the lateral resolution of NSACB measured by the -6-dB mainlobe width can reach as high as 11.11% of delay and sum (DAS), 25.01% of filtered delay multiply and sum (F-DMAS) and 50% of LAG-FDMAS-SCF. The sidelobe level of the NSACB can be reduced at most by 28 dB. Experimental results of simple and complex scatterer phantoms indicate the image resolution of the proposed NSACB can even reach up to 18.76% of DAS, 27.28% of F-DMAS and 14.29% of LAG-FDMAS-SCF. Compared with these methods, the proposed NSACB can reduce the sidelobe level at least by 18 dB.

CONCLUSION

Although the proposed method causes loss of the ability to observe hypo-echoic structures, these results suggest future work to determine the ability to detect breast microcalcifications, kidney stones, biopsy needle tracking and other scenarios requiring scatterer detection.

Non-mass-type ductal carcinoma in situ of the breast on ultrasound: Features and pathological analysis

AIMS

The aims of this study were to investigate the ultrasound features of non-mass-type ductal carcinoma in situ (DCIS) of the breast and conduct a pathological analysis.

MATERIAL AND METHODS

Ultrasound images of 32 cases of non-mass-type DCIS of the breast, collected between September 2014 and June 2016, were analyzed. The characteristics of the lesions, including border, internal echogenicity, local glandular hyperplasia, micro-calcification, and intra-tumoral blood flow resistance index (RI), were analyzed, and a concurrent pathological analysis was conducted.

RESULTS

Obvious local glandular hyperplasia was commonly observed in the 32 cases of non-mass-type DCIS of the breast. The internal echogenicity varied in intensity, exhibiting a "leopard pattern" or "zebra pattern." Color Doppler imaging revealed abundant blood flow signals within the lesion with an RI of >0.7. Isolated duct dilatation and micro-calcifications were occasionally observed within the lesions. High-grade DCIS was the predominant pathological type of non-mass-type DCIS.

CONCLUSIONS

Non-mass-type DCIS of the breast often presents with obvious local glandular hyperplasia and varying internal echogenicity. High-grade DCIS is the frequent pathological type. Color Doppler imaging and RI measurement can assist in diagnosing non-mass-type DCIS of the breast.

Beyond BI-RADS: Nonmass Abnormalities on Breast Ultrasound

Abnormalities on breast ultrasound (US) images which do not meet the criteria for masses are referred to as nonmass lesions. These features and outcomes have been investigated in several studies conducted by Asian researchers. However, the term "nonmass" is not included in the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS) 5th edition for US. According to the Japan Association of Breast and Thyroid Sonology guidelines, breast lesions are divided into mass and nonmass. US findings of nonmass abnormalities are classified into five subtypes: abnormalities of the ducts, hypoechoic areas in the mammary glands, architectural distortion, multiple small cysts, and echogenic foci without a hypoechoic area. These findings can be benign or malignant; however, focal or segmental distributions and presence of calcifications suggest malignancy. Intraductal, invasive ductal, and lobular carcinomas can present as nonmass abnormalities. For the nonmass concept to be included in the next BI-RADS and be widely accepted in clinical practice, standardized terminologies, an interpretation algorithm, and outcome-based evidence are required for both screening and diagnostic US.

The Diagnostic Role of Shear Wave Elastography and Superb Microvascular Imaging in the Evaluation of Suspicious Microcalcifications

OBJECTIVES

The aim of this study was to investigate the role of superb microvascular imaging (SMI) and shear wave elastography (SWE) in the prediction of malignancy and invasiveness of isolated microcalcifications (MC) that can be visualized by ultrasonography (US).

MATERIAL AND METHODS

Sixty-seven women with MC, who were considered suspicious on mammography were evaluated. Only those lesions that could be visualized by US and presented as non-mass lesion were included. They were evaluated by B-mode US, SMI, and SWE before US-guided core-needle biopsy. B-mode US, SMI (vascular index (SMIvi)), and SWE (E-mean, E-ratio) findings were compared with histopathologic features.

RESULTS

Pathology confirmed 45 malignant (21 invasive and 24 in situ carcinomas) and 22 benign lesions. There was a statistically significant difference between malignant and benign groups in terms of size (P = .015), distortion (P = .028), cystic component (P < .001), E-mean (P < .001), E-ratio (P < .001), and SMIvi (P = .006). For differentiation of invasiveness E-mean (P = .002), E-ratio (P = .002), and SMIvi (P = .030) were statistically significant. According to ROC analysis E-mean (cut-off point at 38 kPa) was the most sensitive (78%) and the most specific (95%) value among four numeric parameters (size, SMI, E-mean, and E-ratio) with AUC = 0.895, PPV = 97%, and NPV = 68% in detecting malignancy. In the evaluation of invasiveness, the most sensitive (71.4%) method was SMI (cut-off point at 3.4) and the most specific (72%) method was E-mean (cut-off point at 91.5 kPa).

CONCLUSION

Our study shows that adding SWE and SMI to the sonographic evaluation of MC would be an advantage for US-guided biopsy. Including suspicious areas according to SMI and SWE in the sampling area can help target the invasive part of the lesion and avoid underestimation of core biopsy.

The diagnostic value of contrast-enhanced ultrasonography in breast ductal abnormalities

BACKGROUND

Ductal lesions are an important, often overlooked, and poorly understood issue in breast imaging, which have a risk of underlying malignancy ranging from 5 to 23%. Ultrasonography (US), which has largely replaced galactography or ductography, has become an important imaging method to assess patients with ductal lesions. However, it is difficult to distinguish benign from malignant ductal abnormalities only by ultrasonography, most of which are recommended to be at least in subcategory 4A; these require biopsy according to the ACR BI-RADS®atlas 5th Edition-breast ultrasound. Contrast-enhanced ultrasound (CEUS) has been shown to be valuable for differentiating benign from malignant tumors, but its value is unclear in breast ductal lesions. Therefore, the purposes of this study were to explore the characteristics of malignant ductal abnormalities on US and CEUS imaging and the diagnostic value of CEUS in breast ductal abnormalities.

METHODS

Overall, 82 patients with 82 suspicious ductal lesions were recruited for this prospective study. They were divided into benign and malignant groups according to the pathological results. Morphologic features and quantitative parameters of US and CEUS were analyzed by comparison and multivariate logistic regression to determine the independent risk factors. The diagnostic performance was assessed by receiver operating characteristic (ROC) curve analysis.

RESULTS

Shape, margin, inner echo, size, microcalcification and blood flow classification on US, wash-in time, enhancement intensity, enhancement mode, enhancement scope, blood perfusion defects, peripheral high enhancement and boundary on CEUS were identified as features correlated with malignant ductal lesions. However, multivariate logistic regression showed that only microcalcification (OR = 8.96, P = 0.047) and enhancement scope (enlarged, OR = 27.42, P = 0.018) were independent risk factors for predicting malignant ductal lesions. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy and area under the ROC curve of microcalcifications combined with an enlarged enhancement scope were 0.895, 0.886, 0.872, 0.907, 0.890, and 0.92, respectively.

CONCLUSIONS

Microcalcification and enlarged enhancement scope are independent factors for predicting malignant ductal lesions. The combined diagnosis can greatly improve the diagnostic performance, indicating that CEUS can be useful in the differentiation of benign and malignant lesions to formulate more appropriate management for ductal lesions.

Visualization positioning-guided biopsy of suspicious breast microcalcifications: a retrospective cohort study

Background

At present, most histological evaluations of microcalcifications without a mass are performed using X-ray guided hook wire localization or vacuum-assisted stereotactic biopsy (VASB), but there are still several limitations to these techniques. Therefore, we designed a visualization positioning technique based on three directions of mammography to accurately locate suspected microcalcifications to guide the biopsy.

Methods

We retrospectively analyzed consecutive patients with suspicious microcalcifications who underwent visualization positioning-guided biopsy (VPB) from June 1, 2016, to June 1, 2021. The visualization positioning technique was performed using an electronic ruler to measure the vertical distance from the microcalcification core to the vertical lines on mammography.

Results

A total of 133 patients (median age 46 years; range, 22–87 years) who underwent VPB were included in our study. Among the 133 cases of microcalcifications based on pathological results, 104 were benign, 14 were high risk, and 15 were malignant. In 124 (93.2%) patients, microcalcification was confirmed during the first round of VPB specimen analysis. Only 6 (4.5%) and 3 (2.3%) patients underwent second and third extended resections, respectively, as the resected specimens did not contain microcalcifications. Four patients (3.0%) with malignant biopsy results underwent a subsequent operation. Two patients with DCIS underwent mastectomy and sentinel lymph node biopsy because of diffuse calcification. One patient had no residual cancer, and the other was upgraded to invasive ductal carcinoma (IDC). Two patients with IDC underwent breast-conserving surgery and mastectomy with sentinel lymph node biopsy.

Conclusions

VPB can be used to evaluate breast microcalcifications when a mass is not present, making it an effective diagnostic technique.

Characterization of Suspicious Microcalcifications on Mammography Using 2D Shear-Wave Elastography

Our aim was to investigate the correlations between the findings of two-dimensional shear-wave elastography (2D-SWE) and the histopathologic results of microcalcifications (MCs) visualized using ultrasonography (USG). Fifty people with suspicious MCs without accompanying mass were evaluated. They underwent USG and 2D-SWE before USG-guided tru-cut biopsy. SWE values and histopathologic features were compared statistically. The variables between groups were analyzed using the Mann-Whitney U test. Receiver operating characteristic analysis was performed and cut-off values determined to discriminate malignancy, invasiveness and high grade. Pathology confirmed 27 malignant lesions (18 invasive ductal carcinomas, one invasive lobular and eight ductal carcinomas in situ) and 23 benign ones. There was a statistically significant difference between the SWE values of malignant and benign MCs (p < 0.001). The diagnostic performance of SWE for malignancy, invasiveness and high grade were as follows, repectively: sensitivity (93%, 83%, 88%), specificity (91%, 88%, 53%), positive predictive value (93%, 94%, 44%), negative predictive value (91%, 70%, 90%) and area under the curve (0.952, 0.885, 0.776). Cut-off values were determined as 57 kPa for malignancy, 124 kPa for invasiveness and 124.5 kPa for high grade. In conclusion, SWE is a useful method in clinical practice for characterizing MCs that can be visualized with USG.

Detection rate of breast malignancy of needle localization biopsy of breast microcalcification

OBJECTIVE

The current study aimed to retrospectively assess the cancer detection rate of needle localization biopsy of breast microcalcifications undetectable on sonography.

MATERIALS AND METHODS

Patients who underwent mammography-guided needle localization biopsy of breast microcalcifications undetectable on sonography from January 2005 to December 2017 were included in the study. Patients with incomplete medical records were excluded from the study. Patient mammograms were categorized using the Breast Imaging-Reporting and Data System (BI-RADS) assessment criteria. The percentages of benign and malignant lesions were determined by pathological examination of surgically recovered specimens. Correlation between preoperative imaging assessment and final diagnosis was investigated, and the complications associated with the procedures were recorded.

RESULTS

A total of 301 needle-localized biopsies were performed under mammographic guidance. The mean age of the patients was 58.18 ± 7.73 years. The overall ductal carcinoma in situ (DCIS) and cancer detection rate was 23.3%. The proportion of patients with BI-RADS 0 category and undergoing second mammography was higher in the DCIS and cancer group. A total of 227 patients did not undergo second mammography. Of these patients, 70 demonstrated BI-RADS 4 category, 34 were diagnosed with DCIS, and 5 were diagnosed with breast cancer during subsequent follow-up.

CONCLUSION

Needle-localized excision of microcalcifications undetectable on sonography has high detection rate for early stage of breast cancer with low risk of associated complications. Regular mammography is a satisfactory follow-up tool for female patients with microcalcifications in the breasts. Additional studies should be performed to compare between needle-localized excision and vacuum-assisted breast biopsy.

Advances in Ultrasound-Guided Vacuum-Assisted Biopsy of Breast Microcalcifications

Microcalcification is one of the significant indications for or can even be the sole mammographic feature of breast cancer, especially occult breast cancer. Biopsy and pathologic examination are the most important methods used to identify the nature of suspicious microcalcifications. Stereotactic vacuum-assisted breast biopsy (S-VAB) is the most commonly used biopsy method for microcalcifications currently because of the high detection rate of mammography for microcalcifications. However, in recent years, several clinical studies have gradually found that ultrasound-guided vacuum-assisted breast biopsy (US-VAB) could be an alternative to S-VAB for microcalcifications to some extent, and has its own advantages of flexibility, real-time performance, comfort and high accessibility compared with mammography. An overview of US-VAB of microcalcifications is provided with respect to success rate, diagnostic accuracy, advantages and limitations. On the basis of numerous studies and clinical experience, US-VAB proved to be a valid alternative to S-VAB, with comparable diagnostic accuracy if the microcalcification foci could be detected by ultrasound. And for patients with ultrasound-invisible microcalcifications who are not suitable for or tolerable of S-VAB, US-VAB combined with mammography localization of microcalcifications can also be considered.

Ultrasound evaluation of ductal carcinoma in situ of the breast

PURPOSE

To assess the role of ultrasound (US) in detecting and characterizing ductal carcinoma in situ (DCIS) of the breast and to investigate the correlation between ultrasonographic and biological features of DCIS.

METHODS

In total, 171 patients (mean age 44; range 39-62) with 178 lesions were retrospectively evaluated by two independent radiologists searching for US mass or non-mass lesions. Immunohistochemistry analysis was performed to determine estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression. The US detection rate and pattern distribution among the lesion types were evaluated. The χ² test was used to evaluate the correlation between the US findings and the biological factors. Statistical significance was indicated by p values < 0.05. Inter-observer agreement was calculated by Kohen's k test.

RESULTS

US detected 35% (63/178) of all lesions. Fifty-two (83%) lesions were classified as mass lesions, and 11 (17%) as non-mass lesions (p < 0.0001). Among the mass lesions, the most common shape was irregular (79%; p < 0.0001), with 45 (87%) lesions having indistinct margins. Hypoechogenicity was the most common echo pattern (49 cases, 94%; p < 0.0001). Microcalcifications were found in 23 cases (37%; p = 0.004) and were associated with mass lesions in 15 cases (65%) and with non-mass lesions in 8 cases (35%) (p = 0.21). An almost perfect inter-observer agreement (k = 0.87) was obtained between the two radiologists. A significant ER expression was found in mass lesions (83%; p < 0.0001), with no significant PR (p = 0.89) or HER2 expression (p = 0.81). Among the lesions with microcalcifications, only 7 out of 23 cases (30%) were positive for HER2 (p = 0.09).

CONCLUSION

DCIS represents a heterogeneous pathological process with variable US appearance (mass-like, non-mass-like, or occult). The most common US finding is represented by mass-type, hypoechogenic lesions with indistinct margins. A significant ER expression exists among mass-type lesions, while microcalcifications seem not to be associated with HER2 expression.

Ultrasonographic features of ductal carcinoma in situ: analysis of 219 lesions

Background

The purpose of this paper is to clarify the ultrasonographic features and classification of ductal carcinoma in situ (DCIS), and to evaluate the ability of ultrasonography in the prediction of DCIS.

Methods

The clinical data, gray-scale ultrasound images and pathological results of 219 DCIS lesions that detected in 203 consecutive patients who underwent ultrasonography and surgery in our hospital from January 1, 2014 to December 31, 2019 were collected retrospectively. Ultrasonographic features and classification of DCIS were summarized, and the accuracy of ultrasonography in predicting different ultrasonographic findings of DCIS were compared.

Results

Among the 219 DCIS lesions, 91 (41.6%) presented as mass-like lesions and 128 (58.4%) were non-mass-like lesions. For the 91 mass-like DCIS lesions, 79 were hypoechoic solid masses, 12 were cystic-solid structures. For the 128 non-mass-like DCIS lesions, 114 were hypoechoic areas, 10 were ductal dilatation accompanied with intraductal solid components, and 4 were multiple punctate echogenic foci only. The diagnostic accuracy of ultrasound for the 219 DCIS lesions was 81.7% (179/219). The diagnostic accuracy of mass-like DCIS lesions was 90.1% (82/91), which was significantly higher than that in non-mass-like DCIS lesions [75.8% (97/128), P=0.007]. The diagnostic accuracy of hypoechoic solid masses was significantly higher than those of the other ultrasonographic findings (P=0.002). Ducts abnormalities were detected in 45 (20.5%) lesions and punctate echogenic foci in 134 (61.2%) lesions. The diagnostic accuracy of lesions with ducts abnormalities was 93.3% (42/45), which was significantly higher than that in lesions without ducts abnormalities [78.7% (137/174), P=0.024]. The diagnostic accuracy of lesions with punctate echogenic foci was 92.5% (124/134), which was significantly higher than that in lesions without punctate echogenic foci [64.7% (55/85), P=0.000].

Conclusions

DCIS lesions can effectively be recognized as mass-like lesions and non-mass-like lesions by ultrasound. Hypoechoic areas and hypoechoic solid masses were the most common ultrasonographic features of DCIS. Ducts abnormalities and punctate echogenic foci were helpful for the diagnosis of DCIS.

Value of contrast-enhanced ultrasound in the diagnosis of breast US-BI-RADS 3 and 4 lesions with calcifications

AIM

To evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) for Breast Imaging-Reporting and Data System for Ultrasound (US-BI-RADS) 3 and 4 lesions with calcifications.

MATERIALS AND METHODS

A retrospective study of 168 breast lesions with calcifications detected on both mammography and conventional ultrasonography (US) in 152 patients were categorised as US-BI-RADS 3-4 at US between June 2009 and June 2018. CEUS scores were obtained based on a CEUS five-point scoring system. The combination of US-BI-RADS and CEUS scores created the Rerated BI-RADS (referred to as CEUS-BI-RADS). All results were compared with the histological findings. The diagnostic performances of US and CEUS-BI-RADS were compared.

RESULTS

The diagnostic sensitivity, specificity, and accuracy of US were 81.8% (95% confidence interval [CI]: 71.6%, 92%), 85% (95% CI: 78.4%, 91.5%), and 83.9% (95% CI: 78.4%, 89.5%), respectively, while those for CEUS-BI-RADS were 98.2% (95% CI: 94.7%, 100%), 90.3% (95% CI: 84.8%, 95.7%), and 92.9% (95% CI: 89%, 96.8%), respectively. The diagnostic sensitivity and accuracy values of CEUS-BI-RADS greatly improved compared with those of US (p=0.003 and p=0.004, respectively). The areas under the receiver operating characteristic (ROC) curves for US and CEUS-BI-RADS were 0.888 (95% CI: 0.840, 0.936) and 0.963 (95% CI: 0.936, 0.989), respectively. The diagnostic efficacy of CEUS-BI-RADS was significantly higher than that of US alone (p=0.004).

CONCLUSION

CEUS-BI-RADS significantly improves the diagnostic accuracy for breast US-BI-RADS 3 and 4 lesions with calcifications compared with US.

Does establishing a preoperative nomogram including ultrasonographic findings help predict the likelihood of malignancy in patients with microcalcifications?

BACKGROUND

Mammography (MG) is highly sensitive for detecting microcalcifications, but has low specificity. This study investigates whether establishing a preoperative nomogram including ultrasonographic findings can help predict the likelihood of malignancy in patients with mammographic microcalcification.

METHODS

Between May 2012 and January 2017, 475 patients with suspicious microcalcifications detected on MG underwent ultrasonography (US). The χ² test was used to screen risk factors among the variables. Then, a multivariate logistic regression analysis was performed to identify independent predictors of malignant microcalcifications. A mammographic nomogram (M nomogram) and mammographic-ultrasonographic nomogram (M-U nomogram) were established based on multivariate logistic regression models. The discriminatory ability and clinical utility of both nomograms were compared by the receiver operating characteristics curve and decision curve analysis. The calibration ability was evaluated using a calibration curve.

RESULTS

Among the cases, 68.2% (324/475) were pathologically diagnosed as breast cancer and 31.8% (151/475) were benign lesions. Based on multivariate logistic regression analysis, age, clinical manifestation, morphology and distribution of microcalcifications on MG and lesions associated with microcalcifications on US were confirmed as independent predictors of malignant microcalcifications. In terms of discrimination ability, the C-index of the M-U nomogram was significantly higher than that of the M nomogram (0.917 vs 0.897, p = 0.006). The bias-corrected curve was close to the ideal line in the calibration curve. Decision curve analysis suggested that the M-U nomogram was superior to M nomogram.

CONCLUSIONS

Combining mammographic parameters with ultrasonographic findings in a nomogram provided better performance than an M nomogram alone, especially for dense breasts, which suggests the value of ultrasonographic finding for individualized prediction of malignancy in patients with microcalcifications.

Characterization of Breast Microcalcifications Using a New Ultrasound Image-Processing Technique

OBJECTIVES

To evaluate a new commercial image-processing technique (MicroPure; Toshiba America Medical Systems, Tustin, CA) for detection and characterization of breast microcalcifications in patients undergoing stereotactic or ultrasound-guided biopsies using mammography as the reference standard.

METHODS

One hundred female patients, with a total of 104 lesions, scheduled for an image-guided biopsy of an area with breast microcalcifications (identified on a prior mammogram) underwent MicroPure examinations of the breast using an Aplio XG scanner (Toshiba America Medical Systems) with a broad-bandwidth linear array. MicroPure combines nonlinear imaging and speckle suppression to mark suspected calcifications as white spots in a blue overlay image. Four independent and blinded readers (2 radiologists and 2 physicists) analyzed 208 digital clips consisting of dual grayscale ultrasound and MicroPure imaging, counting the number of microcalcifications seen with MicroPure. The observers also assessed the level of suspicion on a qualitative, visual analog, 6-point scale from 0 (no findings) over 1 (benign) to 5 (malignant).

RESULTS

The mean number of microcalcifications ± SD seen was 6.3 ± 3.5, whereas mammography saw 28.9 ± 24.6 (P = .66). When the MicroPure level of suspicion scores were compared with pathologic results using a receiver operating characteristic curve analysis, the areas under the curve ranged from 0.54 to 0.59. Nonetheless, malignant cases were seen to have significantly more microcalcifications than benign cases (mean number of microcalcifications, 6.9 ± 5.1 versus 5.3 ± 3.7; P = .02).

CONCLUSIONS

MicroPure can be used to identify areas with breast microcalcifications but cannot effectively characterize such areas. Instead, MicroPure may represent a new imaging method for guiding a biopsy to areas of microcalcifications.

US and MRI in the evaluation of mammographic BI-RADS 4 and 5 microcalcifications

PURPOSE

The aim of this study was to assess diagnostic accuracies of ultrasonography (US) and magnetic resonance imaging (MRI) in lesions that manifest as mammographic BI-RADS 4 and 5 microcalcifications, in the setting of conjoined use of mammography, US, and MRI.

METHODS

Patients with mammographic BI-RADS 4 or 5 microcalcifications, without additional findings, were included in this prospective study. All patients subsequently underwent breast US and MRI. Histopathologic diagnosis, obtained by US-guided core-needle biopsy or surgical excision, served as a reference standard. Diagnostic accuracies of US and MRI were calculated, and positive predictive value for different MRI BI-RADS imaging features were determined.

RESULTS

The study group consisted of 113 women with 125 areas of suspicious microcalcifications. MRI reached sensitivity, specificity, positive predictive value 3 (PPV3), and negative predictive value (NPV) of 100%, 70.1%, 67.6%, and 100%, respectively. Statistically significant differences in MRI morphologic features and kinetic enhancement curves were observed between malignant and benign microcalcifications. Sensitivity, specificity, PPV3, and NPV for US were: 85.4%, 66.2%, 61.2%, and 87.9%. There was statistically significant difference in presentation of malignant and benign microcalcifications at US.

CONCLUSION

In the setting of conjoined use of mammography, US, and MRI, MRI can reliably exclude malignancy in suspicious microcalcifications. Thus, negative MRI findings may influence the decision to biopsy the microcalcifications.

Breast ultrasound: recommendations for information to women and referring physicians by the European Society of Breast Imaging

This article summarises the information that should be provided to women and referring physicians about breast ultrasound (US). After explaining the physical principles, technical procedure and safety of US, information is given about its ability to make a correct diagnosis, depending on the setting in which it is applied. The following definite indications for breast US in female subjects are proposed: palpable lump; axillary adenopathy; first diagnostic approach for clinical abnormalities under 40 and in pregnant or lactating women; suspicious abnormalities at mammography or magnetic resonance imaging (MRI); suspicious nipple discharge; recent nipple inversion; skin retraction; breast inflammation; abnormalities in the area of the surgical scar after breast conserving surgery or mastectomy; abnormalities in the presence of breast implants; screening high-risk women, especially when MRI is not performed; loco-regional staging of a known breast cancer, when MRI is not performed; guidance for percutaneous interventions (needle biopsy, pre-surgical localisation, fluid collection drainage); monitoring patients with breast cancer receiving neo-adjuvant therapy, when MRI is not performed. Possible indications such as supplemental screening after mammography for women aged 40-74 with dense breasts are also listed. Moreover, inappropriate indications include screening for breast cancer as a stand-alone alternative to mammography. The structure and organisation of the breast US report and of classification systems such as the BI-RADS and consequent management recommendations are illustrated. Information about additional or new US technologies (colour-Doppler, elastography, and automated whole breast US) is also provided. Finally, five frequently asked questions are answered.

TEACHING POINTS

• US is an established tool for suspected cancers at all ages and also the method of choice under 40. • For US-visible suspicious lesions, US-guided biopsy is preferred, even for palpable findings. • High-risk women can be screened with US, especially when MRI cannot be performed. • Supplemental US increases cancer detection but also false positives, biopsy rate and follow-up exams. • Breast US is inappropriate as a stand-alone screening method.

Precision biopsy of breast microcalcifications: An improvement in surgical excision

The aim of the present study was to improve the conventional wire-guided localization biopsy (WGLB) of breast microcalcifications to overcome disadvantages associated with the procedure, including inaccurate localization and large specimen volume. The novel approach described in the present study was termed double wire-guided localization and rotary cutting biopsy (DWGLB). Prior to surgery, the precise localization of the lesions was assessed using two wires under the assistance of mammography X-ray and ultrasound, followed by complete excision of the lesions using a novel rotary cutting tool. The cylindrical specimen was placed on a scaled specimen holder for pathological examination. DWGLB was performed in 108 patients with the classification of as Breast Imaging Reporting and Data System score 4A. Percutaneous localization of the lesions guided by a mammography X-ray and ultrasound were successful in all 108 lesions (100%) with one puncture attempt. The lesions were precisely excised in all of 108 patients, and included 13 malignant lesions (DCIS of breast in 7 cases, DCIS with focal invasive carcinoma in 3 cases and invasive ductal carcinoma in 3 cases). The average distance of the BARD Dualok to the lesion was 4.1 mm; the average weight of specimens was 8.5 g. Compared with WGLB, DWGLB offers several advantages, including more accurate localization of lesions, a more standardized biopsy method and a smaller specimen volume. DWGLB can also provide the precise position of lesions in the specimen for further pathological examination.

Usefulness of the twinkling artifact on Doppler ultrasound for the detection of breast microcalcifications

OBJECTIVE

To determine whether the twinkling artifact on Doppler ultrasound imaging corresponds to microcalcifications previously seen on mammograms and to evaluate the usefulness of this finding in the ultrasound management of suspicious microcalcifications.

MATERIAL AND METHODS

We used ultrasonography to prospectively examine 46 consecutive patients with groups of microcalcifications suspicious for malignancy identified at mammography, searching for the presence of the twinkling artifact to identify the microcalcifications. Once we identified the microcalcifications, we obtained core-needle biopsy specimens with 11G needles and then used X-rays to check the specimens for the presence of microcalcifications. We analyzed the percentage of detection and obtainment of microcalcifications by core-needle biopsy with this technique and the radiopathologic correlation. Microcalcifications that were not detected by ultrasound or discordant lesions were biopsied by stereotaxy at another center. We also used ultrasound guidance for preoperative marking with clips, usually orienting them radially.

RESULTS

We identified and biopsied 41 of the 46 lesions under ultrasound guidance, including 24 of 25 carcinomas (17 in situ). B-mode ultrasound was sufficient for biopsying the microcalcifications in 14 patients, although the presence of the twinkling artifact increased the number of microcalcifications detected and thus enabled more accurate preoperative marking. Thanks to the twinkling sign, we were able to identify 27 additional groups of microcalcifications (89% vs. 30%; p < 0.05). All the surgical specimens had margins free of disease.

CONCLUSIONS

The twinkling artifact is useful for microcalcifications in ultrasound examinations, enabling a significant increase in the yield of ultrasound-guided biopsies and better preoperative marking of groups of microcalcifications.

Ultrasound Detection of Microcalcifications in Surgical Breast Specimens

The objective was to evaluate a commercial image processing technique (MicroPure, Canon Medical Systems, Tustin, CA, USA) for detection of microcalcifications in breast surgical specimens. Twenty women scheduled for surgical excision of an area with breast calcifications were enrolled, their surgical specimens underwent grayscale ultrasound (US) and MicroPure examination using an Aplio XG scanner (Canon). Four independent and blinded readers analyzed 54 US and 54 MicroPure digital clips to determine the number of calcifications and scored image quality and artifacts on a 10-point scale. All readers saw significantly more microcalcifications with MicroPure than with US, 14.0 ± 12.0 versus 3.0 ± 3.2 (p <0.0001). Three readers preferred MicroPure image quality over that of US (p <0.009) and vice versa for one reader (p = 0.003). Three readers saw fewer Cooper's ligament artifacts with MicroPure than with US (p <0.0001); one reader saw no significance difference between them (p = 0.58). In conclusion MicroPure identified more breast microcalcifications than grayscale US in ex vivo surgical breast specimens.

Compressibility and Density Weighting for Ultrasound Scattering Tomography

A novel reconstruction technique based on delay-and-sum ultrasound tomography algorithms is introduced. This reconstruction technique enables ultrasound tomographic systems to produce compressibility- and density-weighted images (D-WI) for spherically symmetric ultrasound scatterers. The efficacy of this reconstruction technique was demonstrated with simulation and phantom experiments. Separation between a dense wire target and a compressible thread target within a phantom was quantified, showing an increased signal of the wire target for D-WIs. The suppression of background scatter in D-WIs was also quantified. Resolution was calculated for these reconstruction techniques, exemplifying the half-wavelength diffraction-limited resolution capabilities of this ultrasound scattering tomography system. The proposed technique offers a enhanced minimum-detectable density-contrast sensitivity compared to traditional B-scan imaging for a 100- target. This enhanced detectability is expected to prove advantageous for microcalcification imaging.

Non-mass breast lesions on ultrasound: final outcomes and predictors of malignancy

Background Breast cancer can present as non-mass lesions (NMLs) on ultrasound. However, knowledge of and understanding about NMLs are scarce. Purpose To retrospectively investigate the final outcomes of sonographic breast NMLs and determine the clinical and radiologic variables associated with malignancy Material and Methods In our radiologic database of breast ultrasound examinations between 2011 and 2014, we found 119 women with 121 NMLs with available histopathologic or sonographic follow-up (over 2 years) data. We collected the clinical variables (patient's age, symptoms, and mammographic density) and histopathologic data as well as radiologic variables (mammographic and ultrasound findings) after retrospective review by two radiologists, the authors of the current paper, in consensus. We classified the ultrasound findings according to distribution (focal, linear or segmental, and regional) and associated features (calcification, architectural distortion, and ductal changes) and analyzed the associations between variables and malignancy using the t test and χ² test. Results Of the 121 NMLs, 88 (72.7%) were benign and 33 (27.3%) were malignant. Ductal carcinoma in situ (DCIS) (17/33, 51.5%) and invasive ductal cancer with or without DCIS (13/33, 39.4%) comprised the main malignancies, and malignancy was significantly associated with palpability ( P = 0.000). Mammographic findings and sonographic distribution and associated features were significantly different between benign and malignant lesions ( P = 0.000, P = 0.004, and P = 0.001, respectively). Malignant lesions showed more frequent calcifications combined with asymmetry ( P = 0.000) on mammography and linear-segmental distributions ( P = 0.001) and associated calcifications ( P = 0.019) or architectural distortions ( P = 0.015) on ultrasound. Conclusion Breast NMLs on ultrasound showed high risk of malignancy. Symptoms and mammographic and ultrasound findings can be possible predictors of malignancy in NMLs.

Ultrasound Image Classification of Ductal Carcinoma In Situ (DCIS) of the Breast: Analysis of 705 DCIS Lesions

The Japan Association of Breast and Thyroid Sonology (JABTS) proposed, in 2003, a conceptual classification system for non-mass abnormalities to be applied in addition to the conventional concept of masses, to facilitate detecting ductal carcinoma in situ (DCIS) lesions. The aim of this study was to confirm the utility of this system and to clarify the distribution of these findings in DCIS lesions. Data on 705 surgically treated DCIS lesions from 16 institutions in Japan were retrospectively reviewed. All 705 DCIS lesions could be classified according to the JABTS classification system. The most frequent findings were hypo-echoic areas in the mammary gland (48.6%), followed by solid masses (28.0%) and duct abnormalities (10.2%) or mixed masses (8.1%). Distortion (1.3%), clustered microcysts (1.4%) and echogenic foci without a hypo-echoic area (2.5%) were uncommon. These results suggest that the concept of non-mass abnormalities is useful in detecting DCIS lesions.

Detectability and Usefulness of Automated Whole Breast Ultrasound in Patients with Suspicious Microcalcifications on Mammography: Comparison with Handheld Breast Ultrasound

Purpose

The purpose of this study was to prospectively evaluate the detectability and usefulness of automated whole breast ultrasound (AWUS) and to compare it with handheld breast ultrasound (HHUS) in cases with suspicious microcalcifications identified by mammography.

Methods

Forty-two patients with 43 suspicious microcalcifications (25 malignant and 18 benign) detected by mammography underwent AWUS, HHUS, and histol-ogic examination. With knowledge of the mammographic findings, HHUS was performed to assess the visibility of the microcalcifications and the presence of associated masses or ductal changes. Two radiologists reviewed the AWUS images in consensus using the same methods employed for HHUS. Detectability of AWUS was compared with that of HHUS and was correlated with histologic and mammographic findings.

Results

Of the 43 lesions, 32 (74.4%) were detectable by AWUS and 31 (72.1%) by HHUS. No significant differences in sensitivity were found between the two methods (p=0.998). AWUS detected 96% (24/25) of malignant microcalcifications and 44.4% (8/18) of benign microcalcifications. AWUS was more successful in the detection of malignant vs. benign lesions (96.0% vs. 44.4%, p=0.002), lesions >10 mm vs. ≤10 mm in size (86.7% [26/30] vs. 46.2% [6/13], p=0.009), lesions with a fine pleomorphic or linear shape vs. a round or amorphous or coarse heterogeneous shape (94.7% [18/19] vs. 58.3% [14/24], p=0.021), and lesions associated with a mass or architectural distortion vs. without obvious changes on mammography (100% [19/19] vs. 54.2% [13/24], p=0.022).

Conclusion

Detectability of AWUS was comparable to that of HHUS in cases where suspicious microcalcifications were identified on mammography. Therefore, AWUS might be helpful in the performance of ultrasound-guided percutaneous procedures for highly suspicious microcalcifications.

Diagnosis of Columnar Cell Lesions and Atypical Ductal Hyperplasia by Ultrasound-Guided Core Biopsy: Findings Associated with Underestimation of Breast Carcinoma

The aim of the study described here was to determine underestimation rates and identify radiologic predictors of underestimation for columnar cell lesions (CCLs) and atypical ductal hyperplasia (ADH) detected by ultrasound-guided core needle biopsy. A total of 103 CCLs and ADH lesions in 100 patients diagnosed by ultrasound-guided core needle biopsy were evaluated. Breast sonographic and mammographic findings were reviewed, and underestimation rates were determined by surgical excision, percutaneous vacuum-assisted excision or 2-y imaging follow-up. All underestimated lesions were ductal carcinoma in situ, and the underestimation rates of flat epithelial atypia (FEA), FEA + ADH and ADH were 5.9% (1/17), 44.4% (4/9) and 27.3% (12/44), respectively. There was no underestimation of CCLs without atypia. The presence of calcifications on ultrasound was significantly associated with underestimation (p = 0.010). Therefore, except for CCLs without atypia, all other lesions may require excision, especially when calcification is present on ultrasound or when FEA + ADH is found.

Non-stereotactic method involving combination of ultrasound-guided wire localization and vacuum-assisted breast biopsy for microcalcification

BACKGROUND

Stereotactic breast biopsy is a standard intervention for evaluation of "microcalcification-only" lesions. However, an expensive stereotactic device and radiologic expertise are necessary for this procedure. We herein report a non-stereotactic technique involving the combination of wire localization and vacuum-assisted breast biopsy (VABB) under ultrasound (US) guidance.

METHODS

Twenty-two consecutive patients with category 3 or 4a microcalcification only as shown by mammography underwent the above-mentioned non-stereotactic combination method involving US-guided wire localization and VABB. The location of the microcalcification was measured by manual stereotaxis, and the microcalcification was confirmed by specimen mammography after the procedure.

RESULTS

The mean number ± standard deviation of removed cores and calcified cores was 28.4±13.4 and 2.2±0.9, respectively. In one case, the procedure was repeated 3 times. The histologic diagnoses were fibrocystic change (n=14), fibroadenoma (n=4), sclerosing adenosis (n=1), usual ductal hyperplasia (n=2), and atypical ductal hyperplasia (n=1).

CONCLUSIONS

"Microcalcification-only" breast lesions can be easily evaluated with the combination of non-stereotactic US-guided wire localization and VABB. This would be an effective diagnostic technique for breast lesion which reveals only microcalcification.

[Explorations of breast microcalcifications: Guidelines]

OBJECTIVES

To assess imaging performances for the detection, characterization and biopsy of breast microcalcifications and make recommendations.

MATERIALS AND METHODS

French and English publications were searched using PubMed, Cochrane Library and international learned societies recommendations.

RESULTS

Digital mammography (DR [Direct Radiography] and CR [Computed Radiography]) and screen-film mammography demonstrate good performances for the detection and the characterization of breast microcalcifications. Systematic use of the 2013 edition of the BI-RADS lexicon is recommended for description and characterization of microcalcifications. Faced with BI-RADS 4 or 5 microcalcifications, breast ultrasound is recommended but a normal result does not eliminate the diagnosis of cancer and other examination should be performed. Literature review does not allow recommending digital breast tomosynthesis, elastography or MRI to analyze microcalcifications. In case of probably benign microcalcifications (BI-RADS 3), six months, one year and at least two years follow-up are recommended. In case a biopsy is indicated, it is recommended to use a vacuum-assisted macrobiopsy system with 11-gauges needles or bigger. If no calcification is visible on the radiography of the specimen, it is recommended to obtain additional samples.

Sonographic Features of Ductal Carcinoma In Situ of the Breast With Microinvasion: Correlation With Clinicopathologic Findings and Biomarkers

OBJECTIVES

To compare the sonographic results, clinicopathologic characteristics, and biomarkers in pure ductal carcinoma in situ (DCIS) of the breast and DCIS with microinvasion.

METHODS

A total of 218 patients with pathologically proven DCIS based on sonography in our hospital (2009-2013) were retrospectively enrolled. Clinicopathologic characteristics and biomarkers were examined. Grayscale sonographic results were investigated according to the American College of Radiology Breast Imaging Reporting and Data System lexicon, and color Doppler sonography was used to assess the vascularization distribution and degree. All variables were compared by univariate and multivariate logistic regression analyses.

RESULTS

All patients were female, with a mean age of 55.3 years (range, 32-78 years). One hundred sixty patients with 160 lesions had pure DCIS, and 58 patients with 58 lesions had DCIS with microinvasion. Ductal carcinoma in situ with microinvasion was more likely to have sentinel lymph node metastases, larger tumors, a higher tumor grade, human epidermal growth factor receptor 2 positivity, and a high Ki-67 index (all P < .05). Univariate analysis showed that DCIS with microinvasion was more likely to be hypoechoic with microcalcifications, have a mixed vascularization distribution (equal peripheral and internal blood flow signals), and have a high degree of vascularization (at least 2 penetrating vessels; all P < .05). Multivariate analysis indicated that the presence of microcalcifications and a high degree of vascularization were significantly and independently associated with microinvasion (both P < .001).

CONCLUSIONS

Our findings suggest that DCIS with microinvasion is more likely to have microcalcifications and a high degree of vascularization than pure DCIS. Patients with these sonographic features are more likely to have a high tumor grade, sentinel lymph node metastases, larger tumors, a high Ki-67 index, and human epidermal growth factor receptor 2 positivity.

Breast Microcalcifications: Diagnostic Outcomes According to Image-Guided Biopsy Method

OBJECTIVE

To evaluate the diagnostic outcomes of ultrasonography-guided core needle biopsy (US-CNB), US-guided vacuum-assisted biopsy (US-VAB), and stereotactic-guided vacuum-assisted biopsy (S-VAB) for diagnosing suspicious breast microcalcification.

MATERIALS AND METHODS

We retrospectively reviewed 336 cases of suspicious breast microcalcification in patients who subsequently underwent image-guided biopsy. US-CNB was performed for US-visible microcalcifications associated with a mass (n = 28), US-VAB for US-visible microcalcifications without an associated mass (n = 59), and S-VAB for mammogram-only visible lesions (n = 249). Mammographic findings, biopsy failure rate, false-negative rate, and underestimation rate were analyzed. Histological diagnoses and the Breast Imaging Reporting and Data System (BI-RADS) categories were reported.

RESULTS

Biopsy failure rates for US-CNB, US-VAB, and S-VAB were 7.1% (2/28), 0% (0/59), and 2.8% (7/249), respectively. Three false-negative cases were detected for US-CNB and two for S-VAB. The rates of biopsy-diagnosed ductal carcinoma in situ that were upgraded to invasive cancer at surgery were 41.7% (5/12), 12.9% (4/31), and 8.6% (3/35) for US-CNB, US-VAB, and S-VAB, respectively. Sonographically visible lesions were more likely to be malignant (66.2% [51/77] vs. 23.2% [46/198]; p < 0.001) or of higher BI-RADS category (61.0% [47/77] vs. 22.2% [44/198]; p < 0.001) than sonographically invisible lesions.

CONCLUSION

Ultrasonography-guided vacuum-assisted biopsy is more accurate than US-CNB when suspicious microcalcifications are detected on US. Calcifications with malignant pathology are significantly more visible on US than benign lesions.

Correlation between sonographic findings and clinicopathologic and biologic features of pure ductal carcinoma in situ in 691 patients

OBJECTIVE

The objective of our study was to compare the sonographic features of pure ductal carcinoma in situ (DCIS) lesions with the initial clinical presentation and histopathologic findings.

MATERIALS AND METHODS

The images and records of 691 patients with pure DCIS who underwent preoperative mammography and whole-breast sonography as part of staging workup in a single institution from January 1, 1996, through July 31, 2009, were reviewed. The BI-RADS sonography lexicon was used when reviewing the sonographic studies. Histopathologic features recorded included estrogen receptor (ER) status, nuclear grade, and presence or absence of comedonecrosis. Statistical comparisons were made using the Student t test, chi-square test, Fisher exact test, Kruskal-Wallis or Wilcoxon rank sum test, multiple logistic regression analysis, and Pearson correlation coefficient.

RESULTS

A total of 304 (44%) tumors were visible on mammography and sonography; 315 (46%), on mammography only; 58 (8%), on sonography only; and 14 (2%), on neither mammography nor sonography. The most common sonographic appearance of DCIS was an irregular hypoechoic mass with indistinct margins and normal posterior features that was indistinguishable from invasive carcinoma. Patients with symptomatic high-nuclear-grade DCIS, dense breasts, and comedonecrosis were younger and had larger tumors on sonography than asymptomatic women with nondense breasts and low-nuclear-grade and noncomedo DCIS. Women with ER-negative DCIS were older and had larger tumors on sonography than women with ER-positive DCIS. ER-negative tumors were more frequently visible on sonography than ER-positive tumors (p=0.007). High-grade DCIS (p<0.0001) and comedo DCIS (p<0.0001) presented more frequently as microcalcifications, architectural distortion, and ductal changes on sonography than low-grade DCIS or noncomedo DCIS.

CONCLUSION

Of the 691 pure DCIS lesions, 362 (52%) were visible on sonography and presented most commonly as a mass. Lesion visibility of DCIS on sonography was not related to nuclear grade or the presence of comedonecrosis.

Incidental Breast Lesions Identified by (18)F-FDG PET/CT: Which Clinical Variables Differentiate between Benign and Malignant Breast Lesions?

Purpose

The aim of our study was to evaluate the risk of malignancy and to determine which clinical variables differentiate between benign and malignant focal breast lesions found incidentally on ¹⁸F-flourodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT).

Methods

From March 2005 to October 2011, 21,224 women with no history of breast cancer underwent FDG PET/CT at three university-affiliated hospitals. We retrospectively identified 214 patients with incidental focal hypermetabolic breast lesions and grouped them into benign and malignant lesion groups. Of the 214 patients, 82 patients with 91 lesions were included in this study. All lesions were confirmed histologically or were assessed by follow-up imaging for greater than 2 years. The patient age, maximum standardized uptake value (SUV_max), lesion size on ultrasonography (US), and Breast Imaging-Reporting and Data System (BI-RADS) category on US in conjunction with mammography were compared between the groups. Multivariate logistic regression analysis was used to identify independent factors associated with malignancy.

Results

The risk of malignancy was 29.7% (27/91) in breast incidentalomas detected by FDG PET/CT. The univariate analysis showed that the patient age, SUV_max, tumor size, and BI-RADS category differed significantly between the malignant and benign groups. The multivariate analysis showed that the BI-RADS category was the only significant factor differentiating benign from malignant lesions (p=0.002).

Conclusion

BIRADS category based on US in conjunction with mammography was the only useful tool to differentiate between malignant and benign lesions in breast incidentalomas on FDG PET/CT.

Interventional radiology in the diagnosis and treatment of diseases of the breast: a historical review and future perspective based on currently available techniques

OBJECTIVE

The topic of imaging-guided breast interventions spans more than 30 years. Radiologists pioneered procedures such as needle or wire localization and ultrasound and stereotactic-guided biopsy. Using recently developed devices and technology, the opportunity exists to treat lesions of the breast with minimally invasive imaging-guided techniques.

CONCLUSION

Breast imagers and interventional radiologists, along with our surgical and oncologic colleagues, are best qualified to participate together in the research and development of these procedures.

Breast ultrasound for the interventionalist

Ultrasound (US)-guided interventional procedures are routinely performed for lesions visualized on US and are the standard of care in the diagnosis and management of breast disease. When performed correctly, these procedures are safe, minimally invasive, and have a high diagnostic accuracy comparable to surgical biopsy. The most commonly performed US-guided procedures include fine-needle aspiration, core needle biopsy, and preoperative wire localization. The success of these procedures depends on a thorough understanding of the indications, strong technical skills, and appropriate postbiopsy management. This article reviews the indications and techniques for US-guided interventional procedures. Concordance of imaging and pathology results, potential challenges, and associated complications are also discussed.

Non-mass-like breast lesions at ultrasonography: feature analysis and BI-RADS assessment

OBJECTIVE

To analyze the features of non-mass-like (NML) breast lesions on ultrasound (US) and determine their corresponding malignancy rate and to stratify these lesion patterns according to US BI-RADS categories.

MATERIALS AND METHODS

One hundred sixty-four consecutive lesions were retrospectively classified into four types according to the US features, the corresponding positive predictive values (PPVs) were obtained. Clinical, imaging, and histopathological findings were reviewed.

RESULTS

Among the 164 lesions, 39 (24%) were classified as type Ia, 14 (8%) as type Ib, 39 (24%) as type IIa, 19 (12%) as type IIb, 19 (12%) as type III, and 34 (21%) as type IV. The PPVs for malignancy were 21% for type Ia, 79% for type Ib, 10% for type IIa, 58% for type IIb, 16% for type III, and 21% for type IV. All NML lesions were classified as BI-RADS category 4a (type IIa), 4b (type Ia, III and IV) and 4c (type Ib and IIb) according to their PPVs. There was a significantly higher frequency of malignancy among lesions of type Ib and type IIb compared with the other types (P<0.01 for each). Lesions with associated calcifications, presence of abnormal axillary nodes, or a mammographic finding of suspected malignancy had a higher probability of malignancy (P<0.05 for each).

CONCLUSION

US is useful in clarifying the indication for biopsy of NML lesions. The types of US classifications used in our study establish reliable references for the NML patterns when stratified according to the BI-RADS categories.

Photoacoustic imaging of breast microcalcifications: a preliminary study with 8-gauge core-biopsied breast specimens

Background

We presented the photoacoustic imaging (PAI) tool and to evaluate whether microcalcifications in breast tissue can be detected on photoacoustic (PA) images.

Methods

We collected 21 cores containing microcalcifications (n = 11, microcalcification group) and none (n = 10, control group) in stereotactic or ultrasound (US) guided 8-gauge vacuum-assisted biopsies. Photoacoustic (PA) images were acquired through ex vivo experiments by transmitting laser pulses with two different wavelengths (700 nm and 800 nm). The presence of microcalcifications in PA images were blindly assessed by two radiologists and compared with specimen mammography. A ratio of the signal amplitude occurring at 700 nm to that occurring at 800 nm was calculated for each PA focus and was called the PAI ratio.

Results

Based on the change of PA signal amplitude between 700 nm and 800 nm, 10 out of 11 specimens containing microcalcifications and 8 out of 10 specimens without calcifications were correctly identified on blind review; the sensitivity, specificity, accuracy, positive predictive and negative predictive values of our blind review were 90.91%, 80.0%, 85.71%, 83.33% and 88.89%. The PAI ratio in the microcalcification group was significantly higher than that in the control group (the median PAI ratio, 2.46 versus 1.11, respectively, P = .001). On subgroup analysis in the microcalcification group, neither malignant diagnosis nor the number or size of calcification-foci was proven to contribute to PAI ratios.

Conclusion

Breast microcalcifications generated distinguishable PA signals unlike breast tissue without calcifications. So, PAI, a non-ionizing and non-invasive hybrid imaging technique, can be an alternative in overcoming the limitations of conventional US imaging.

Discrimination of breast microcalcifications using a strain-compounding technique with ultrasound speckle factor imaging

The usefulness of breast ultrasound could be extended by improving the detection of microcalcifications by being able to detect and enhance microcalcifications while simultaneously eliminating hyperechoic spots (e.g., speckle noise and fibrocystic changes) that can be mistaken for microcalcifications (i.e., false microcalcifications). This study investigated the use of a strain-compounding technique with speckle factor (SF) imaging to analyze the degree of scatterer redistributions in breast tissues under strain conditions for identifying microcalcifications and false microcalcifications. The efficacy of the proposed method was tested by collecting raw data of ultrasound backscattered signals from 26 lesions at BI-RADS category 4 or 5 with suspicious microcalcifications. The different strain conditions were created by applying manual compression to deform the breast lesion. For each region in which microcalcifications were suspected, estimates of the SNR of the strain-compounding B-scan images and estimates of the mean SF (SFavg) in the strain-compounding SF images were calculated. Compared with microcalcifications, the severity of speckle of the false microcalcifications would be easily degraded under compressive strain conditions. The results demonstrated that the SNR estimates in the strain-compounding B-scan images for microcalcifications and false microcalcifications were 5.22 ± 1.04 (mean ± standard deviation) and 4.62 ± 1.09, respectively; the corresponding SFavg estimates in the strain-compounding SF images were 0.47 ± 0.10 and 0.22 ± 0.10 (p < 0.01). The mean area under the receiver operating characteristic curve using the SNR estimate was 0.71, whereas that using the SFavg estimate was 0.94. These findings indicate that the strain-compounding SF imaging method is more effective at discriminating between microcalcifications and false microcalcifications.

Nonmasslike lesions on breast sonography: comparison between benign and malignant lesions

OBJECTIVES

To compare the imaging and clinical features of benign and malignant nonmasslike lesions in the breast.

METHODS

During a 2-year period at a single institution, 186 nonmasslike lesions in 158 women were pathologically confirmed through surgery or sonographically guided biopsy. The sonographic patterns (mottled, geographic, and indistinct) and distributions (focal and regional) were compared between benign and malignant lesions. The presence of sonographically visible calcifications, amount of color Doppler signals, presence of positive findings on mammography, and presence of symptoms were also compared between the two groups.

RESULTS

A total of 156 lesions (84%) were confirmed as benign and 30 (16%) as malignant. On sonography, malignant nonmasslike lesions more frequently had mottled and geographic patterns and regional distribution than benign lesions (P < .0001). Malignant lesions also more frequently had sonographically visible calcifications (40% versus 0%; P < 0.0001) and a greater amount of color Doppler signals than benign lesions (P < .0001). On mammography, malignant lesions more frequently had densities and calcifications than benign lesions (30.4% versus 7.1%; P = 0.0052; 73.9% versus 6.1%; P < .0001, respectively). Clinically, malignant lesions were more frequently palpable and accompanied by localized pain than benign lesions (50% versus 2.6%; P< .0001; 13.3% versus 0.6%; P = .0025).

CONCLUSIONS

The imaging and clinical features of malignant nonmasslike lesions differed significantly from those of benign nonmasslike lesions.

Retrieval rate and accuracy of ultrasound-guided 14-G semi-automated core needle biopsy of breast microcalcifications

Objective

To evaluate the retrieval rate and accuracy of ultrasound (US)-guided 14-G semi-automated core needle biopsy (CNB) for microcalcifications in the breast.

Materials and Methods

US-guided 14-G semi-automated CNB procedures and specimen radiography were performed for 33 cases of suspicious microcalcifications apparent on sonography. The accuracy of 14-G semi-automated CNB and radiology-pathology concordance were analyzed and the microcalcification characteristics between groups with successful and failed retrieval were compared.

Results

Thirty lesions were successfully retrieved and the microcalcification retrieval rate was 90.9% (30/33). Thirty lesions were successfully retrieved. Twenty five were finally diagnosed as malignant (10 invasive ductal carcinoma, 15 ductal carcinoma in situ [DCIS]) and five as benign. After surgery and mammographic follow-up, the 25 malignant lesions comprised 12 invasive ductal carcinoma and 13 DCIS. Three lesions in the failed retrieval group (one DCIS and two benign) were finally diagnosed as two DCIS and one benign after surgery. The accuracy of 14-G semi-automated CNB was 90.9% (30/33) because of two DCIS underestimates and one false-negative diagnosis. The discordance rate was significantly higher in the failed retrieval group than in the successful retrieval group (66.7% vs. 6.7%; p < 0.05). Punctate calcifications were significantly more common in the failed retrieval group than in the successful retrieval group (66.7% vs. 3.7%; p < 0.05).

Conclusion

US-guided 14-G semi-automated CNB could be a useful procedure for suspicious microcalcifications in the breast those are apparent on sonography.

Breast US in patients with breast cancer presenting as only microcalcifications on mammography: can US differentiate ductal carcinoma in situ from invasive cancer?

PURPOSE

To retrospectively review sonographic findings of breast cancers presenting as only microcalcifications on mammography and to evaluate factors essential for differentiating ductal carcinoma in situ (DCIS) from invasive cancers.

METHODS

We retrospectively reviewed the medical records of 620 consecutive patients with confirmed breast cancer according to surgery performed between March 2008 and October 2011 at our institution. Of these, 53 lesions from 52 patients who had only microcalcifications without a mass or other associated findings on mammography were selected. Sonographic findings of microcalcification areas were analyzed and correlated with the histopathological findings.

RESULTS

Of the 53 lesions, 26 (49.18 %) were classified as invasive cancer and 27 (50.9 %) as DCIS. Ultrasonography (US) showed only echogenic calcifications in five (9.4 %), calcifications within hypoechoic parenchymal thickening in 14 (26.4 %), calcifications within ductal changes in three (5.7 %), and calcifications within a mass in 14 (26.4 %). Seventeen (32.1 %) lesions were not visible on US. Negative findings in US were more frequently observed for DCIS (n = 15, 55.6 %) than for invasive cancers (n = 2, 7.7 %) (p < 0.001). Masses (n = 11, 42.3 % of invasive cancer; n = 3, 11.1 % of DCIS; p = 0.01) were more frequently observed in invasive cancers than in DCIS.

CONCLUSIONS

US findings of breast cancers presenting as only mammographic microcalcifications were significantly different between DCIS and invasive cancers. Targeted US of microcalcifications might be helpful for predicting invasive cancers and for determining the clinical preoperative work-up, including axillary staging.

Breast ultrasonography: state of the art

Ultrasonography (US) is an indispensable tool in breast imaging and is complementary to both mammography and magnetic resonance (MR) imaging of the breast. Advances in US technology allow confident characterization of not only benign cysts but also benign and malignant solid masses. Knowledge and understanding of current and emerging US technology, along with the application of meticulous scanning technique, is imperative for image optimization and diagnosis. The ability to synthesize breast US findings with multiple imaging modalities and clinical information is also necessary to ensure the best patient care. US is routinely used to guide breast biopsies and is also emerging as a supplemental screening tool in women with dense breasts and a negative mammogram. This review provides a summary of current state-of-the-art US technology, including elastography, and applications of US in clinical practice as an adjuvant technique to mammography, MR imaging, and the clinical breast examination. The use of breast US for screening, preoperative staging for breast cancer, and breast intervention will also be discussed.

Sonographic findings of pure ductal carcinoma in situ

PURPOSE

To investigate the characteristic sonographic (US) findings of pure ductal carcinoma in situ (DCIS) in a large series.

METHODS

We retrospectively reviewed the US findings of 126 cases of pure DCIS in 123 consecutive patients who underwent surgery for breast cancer in our hospital. We analyzed the US findings of the lesions according to mass or nonmass abnormality, shape, margin, orientation, echogenicity, echotexture, boundary echo, posterior acoustic features, presence of associated ductal dilatation, presence of intralesional cystic focus, and presence of microcalcifications on US. We compared the US characteristics of pure DCIS with and without mammographic microcalcifications.

RESULTS

Seventy-eight cases of pure DCIS had microcalcifications and 48 had no microcalcifications on mammography (MG). Overall, 109 cases (86.5%) of pure DCIS were demonstrated on US. DCIS with microcalcifications on MG showed positive US findings in 79.5% of cases. The most common US finding was heterogeneous hyper- or isoechoic parenchyma with intralesional microcalcifications and without posterior acoustic features. DCIS without microcalcifications on MG showed positive US findings in 97.9% of cases. The most common US findings were masses with round or oval shape, microlobulated margin, parallel orientation, heterogeneous mild hypoechogenicity, and without boundary echo or posterior acoustic features. Ductal dilatations and intralesional cystic foci were present in 17.5% (22/126) and 23.8% (30/126) of pure DCIS, respectively.

CONCLUSIONS

Overall, US could demonstrate 85.7% of pure DCIS cases, including 16 (12.7%) cases of clinically and mammographically occult pure DCIS. DCIS with and without microcalcifications on MG showed different US characteristics.

Mammography in combination with breast ultrasonography versus mammography for breast cancer screening in women at average risk

BACKGROUND

Breast cancer is the most common malignant disease diagnosed in women worldwide. Screening with mammography has the ability to detect breast cancer at an early stage. The diagnostic accuracy of mammography screening largely depends on the radiographic density of the imaged breasts. In radiographically dense breasts, non-calcified breast cancers are more likely to be missed than in fatty breasts. As a consequence, some cancers are not detected by mammography screening. Supporters of adjunct ultrasonography to the screening regimen for breast cancer argue that it might be a safe and inexpensive approach to reduce the false negative rates of the screening process. Critics, however, are concerned that performing supplemental ultrasonography on women at average risk will also increase the rate of false positive findings and can lead to unnecessary biopsies and treatments.

OBJECTIVES

To assess the comparative effectiveness and safety of mammography in combination with breast ultrasonography versus mammography for breast cancer screening for women at average risk of breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group's Specialised Register, MEDLINE (via OvidSP) and EMBASE up until February 2012.To detect ongoing or unpublished studies, we searched the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov and the National Cancer Institute's clinical trial database until June 2012. In addition, we conducted grey literature searches using the following sources: OpenGrey; National Institute of Health RePORTER; Health Services Research Projects in Progress (HSRPROJ); Hayes, Inc. Health Technology Assessment; The New York Academy of Medicine's Grey Literature Index and Conference Papers Index.

SELECTION CRITERIA

For efficacy, we considered randomised controlled trials (RCTs), with either individual or cluster randomisation, and prospective, controlled non-randomised studies with a low risk of bias and a sample size of at least 500 participants.In addition to studies eligible for efficacy, we considered any controlled, non-randomised study with a low risk of bias and a study size of at least 500 participants for the assessment of harms.Our population of interest were women between the ages of 40 and 75 years who were at average risk for breast cancer.

DATA COLLECTION AND ANALYSIS

Two review authors screened abstracts and full-text publications against the inclusion criteria. None of the studies met our inclusion criteria.

MAIN RESULTS

Our review did not detect any controlled studies on the use of adjunct ultrasonography for screening in women at average risk for breast cancer. One ongoing randomised controlled trial was identified (J-START, Japan).

AUTHORS' CONCLUSIONS

Presently, there is no methodologically sound evidence available justifying the routine use of ultrasonography as an adjunct screening tool in women at average risk for breast cancer.

Training the ACRIN 6666 Investigators and effects of feedback on breast ultrasound interpretive performance and agreement in BI-RADS ultrasound feature analysis

OBJECTIVE

Qualification tasks in mammography and breast ultrasound were developed for the American College of Radiology Imaging Network (ACRIN) 6666 Investigators. We sought to assess the effects of feedback on breast ultrasound interpretive performance and agreement in BI-RADS feature analysis among a subset of these experienced observers.

MATERIALS AND METHODS

After a 1-hour didactic session on BI-RADS: Ultrasound, an interpretive skills quiz set of 70 orthogonal sets of breast ultrasound images including 25 (36%) malignancies was presented to 100 experienced breast imaging observers. Thirty-five observers reviewed the quiz set twice: first without and then with immediate feedback of consensus feature analysis, management recommendations, and pathologic truth. Observer performance (sensitivity, specificity, area under the curve [AUC]) was calculated without feedback and with feedback. Kappas were determined for agreement on feature analysis and assessments.

RESULTS

For 35 observers without feedback, the mean sensitivity was 89% (range, 68-100%); specificity, 62% (range, 42-82%); and AUC, 82% (range, 73-89%). With feedback, the mean sensitivity was 93% (range, 80-100%; mean increase, 4%; range of increase, 0-12%; p < 0.0001), the mean specificity was 61% (range, 45-73%; mean decrease, 1%; range of change, -18% to 11%; p = 0.19), and the mean AUC was 84% (range, 78-90%; mean increase, 2%; range of change, -3% to 9%; p < 0.0001). Three breast imagers in the lowest quartile of initial performance showed the greatest improvement in sensitivity with no change or improvement in AUC. The kappa values for feature analysis did not change, but there was improved agreement about final assessments, with the kappa value increasing from 0.53 (SE, 0.02) without feedback to 0.59 (SE, 0.02) with feedback (p < 0.0001).

CONCLUSION

Most experienced breast imagers showed excellent breast ultrasound interpretive skills. Immediate feedback of consensus BI-RADS: Ultrasound features and histopathologic results improved performance in ultrasound interpretation across all experience variables.