Clinical application of the BI-RADS final assessment to breast sonography in conjunction with mammography

Comparative analysis of automated breast volume scanner (ABVS) combined with conventional hand-held ultrasound and mammography in female breast cancer detection

Objective and background

This study aimed to compare the diagnostic value of an automated breast volume scanner (ABVS) combined with conventional hand-held ultrasound and mammography in detecting female breast cancer. Early detection is vital in improving patient outcomes for this prevalent disease.

Methods

Seventy-eight suspicious breast lesions from 60 patients were examined between August 2019 and July 2020. Each patient underwent ABVS, conventional hand-held ultrasound, and mammography. Diagnostic values, including coincidence rate, sensitivity, specificity, positive predictive value, and negative predictive value, were calculated using histopathology results as the "gold standard."

Results

Histopathology confirmed 55 malignant (70.51%) and 23 benign lesions (29.48%). ABVS combined with conventional hand-held ultrasound identified 56 malignant (52 confirmed, 4 benign) and 22 benign nodules (3 confirmed, 19 benign). Mammography detected 48 malignant (45 confirmed, 3 benign) and 30 benign nodules (10 confirmed, 20 benign). ABVS combined with conventional hand-held ultrasound had a sensitivity of 94.5%, specificity of 82.6%, positive predictive value of 92.9%, and negative predictive value of 86.4%. Mammography showed a sensitivity of 81.8%, specificity of 87.0%, positive predictive value of 93.8%, and negative predictive value of 66.7%.

Conclusion

ABVS combined with conventional hand-held ultrasound showed high diagnostic value in detecting female breast cancer. The "convergence sign" in the coronal section played a significant role. It slightly outperformed mammography and offered advantages in terms of cost, convenience, comfort, and absence of radiation. Further promotion and implementation are supported.

Principal component regression-based contrast-enhanced ultrasound evaluation system for the management of BI-RADS US 4A breast masses: objective assistance for radiologists

A portion of detected breast masses might be overrated by using the Breast Imaging-Reporting and Data System ultrasonography (BI-RADS US) lexicon. A principal component regression-based contrast-enhanced ultrasound (PCR-CEUS) evaluation system was built to quantitatively illustrate whether CEUS could help radiologists to differentiate 4A masses. The PCR-CEUS evaluation system, based on principal component analysis (PCA) and logistic regression, was verified by random assignment into training and test sets and shown to reduce the data dimension and avoid collinearity in CEUS variables. This prospective study consecutively collected 238 patients with 238 4A masses confirmed pathologically. All enrolled patients accepted CEUS examination. The diagnostic performance of senior and junior radiologists, PCR-CEUS and combined methods was compared. The PCR-CEUS system had consistent diagnostic performance in both the training and test sets, with an area under the curve (AUC) of 0.831 (0.765-0.897), 0.798 (0.7034-0.892) and 0.854 (0.765-0.943) (all P > 0.05). The AUC of the combined diagnostic model (PCR-CEUS + Senior radiologists) was higher than that of senior radiologists, and the combined model had higher sensitivity (0.875 (0.781-0.969) vs. 0.729 (0.603-0.855)) without compromising specificity. Furthermore, the AUC and specificity of the combined model (PCR-CEUS + Junior radiologists) (0.852 (0.787-0.916)) was higher than that of junior radiologists (0.665 (0.592-0.737) (P < 0.00001)). PCR-CEUS demonstrated good ability in differentiating malignant BI-RADS-US 4A masses and was helpful for both senior and junior radiologists.

Mammography breast density: an effective supplemental modality for the precise grading of ultrasound BI-RADS 4 categories

Background

High breast density is significantly associated with an increased risk of breast diseases. Presently, suspected breast masses assessed as Breast Imaging-Reporting and Data System (BI-RADS) grade 4 provide a wide range of positive predictive values. Moreover, subcategories (4a, 4b, and 4c) are still under consideration as the diagnostic criteria are neither comprehensive nor objective. However, whether mammography breast density (MBD) has any impact on the accurate grading of BI-RADS 4 assessed by ultrasound (US) remains unknown.

Methods

A total of 1,086 women with 1,293 breast masses were included and assessed as BI-RADS 3-5 by US. The subcategories of MBD (from the ACR-a to the ACR-d group) were assessed by mammography according to the criteria of the American College of Radiology (ACR). The clinicopathological characteristics of these patients were reviewed retrospectively. The malignancy rates of breast masses among different subgroups assessed by BI-RADS were re-estimated with MBD.

Results

Almost all BI-RADS 3 masses were classified as benign and nearly all BI-RADS 5 masses were identified as malignant. Significant inverse associations between MBD and malignancy rates were detected between the BI-RADS 4a and BI-RADS 4b groups. Moreover, malignancy rates decreased significantly from ACR-a to ACR-d for BI-RADS 4a and 4b breast lesions (P<0.001). However, this trend was not observed in BI-RADS 4c breast lesions.

Conclusions

MBD could serve as a crucial factor for the accurate grading of BI-RADS 4 lesions assessed by US. We strongly recommend the adoption of the MBD as a possible supplemental screening modality for US. Furthermore, it is equally beneficial for accurate risk assessment and screening recommendations based on MBD.

Risk-predicted dual nomograms consisting of clinical and ultrasound factors for downgrading BI-RADS category 4a breast lesions - A multiple centre study

Purpose: To develop and to validate a risk-predicted nomogram for downgrading Breast Imaging Reporting and Data System (BI-RADS) category 4a breast lesions. Patients and Methods: We enrolled 680 patients with breast lesions that were diagnosed as BI-RADS category 4a by conventional ultrasound from December 2018 to June 2019. All 4a lesions were randomly divided into development and validation groups at the ratio of 3:1. In the development group consisting of 499 cases, the multiple clinical and ultrasound predicted factors were extracted, and dual-predicted nomograms were constructed by multivariable logistic regression analysis, named clinical nomogram and ultrasound nomogram, respectively. Patients were twice classified as either "high risk" or "low risk" in the two nomograms. The performance of these dual nomograms was assessed by an independent validation group of 181 cases. Receiver Operating Characteristic (ROC) curve and diagnostic value were calculated to evaluate the applicability of the new model. Results: After multiple logistic regression analysis, the clinical nomogram included 2 predictors: age and the first-degree family members with breast cancer. The area under the curve (AUC) value for the clinical nomogram was 0.661 and 0.712 for the development and validation groups, respectively. The ultrasound nomogram included 3 independent predictors (margins, calcification and strain ratio), and the AUC value in this nomogram was 0.782 and 0.747 in the development and validation groups, respectively. In the development group of 499 patients, approximately 50.90% (254/499) of patients were twice classified "low risk", with a malignancy rate of 1.18%. In the validation group of 181 patients, approximately 47.51% (86/181) of patients had been twice classified as "low risk", with a malignancy rate of 1.16%. Conclusions: A dual-predicted nomogram incorporating clinical factors and imaging characteristics is an applicable model for downgrading the low-risk lesions in BI-RADS category 4a and shows good stability and accuracy, which is useful for decreasing the rate of invasive examinations and surgery.

Discrepancies between radiological and histological findings in preoperative core needle (CNB) and vacuum-assisted (VAB) breast biopsies

Background

Ultrasound (US)-guided breast biopsy is a routine diagnostic method used to correlate imaging finding to a histological diagnosis which is still the gold standard in preoperative diagnostics. The accuracy of US-guided breast biopsies relies on a precise radiologic-histopathologic correlation, which is discussed amongst an interdisciplinary team of gynecologists, radiologists and pathologists. However, false-negative or non-diagnostic biopsy results occur. Hence, a thorough and honest discussion to clarify the reason for discrepancies and to decide the next diagnostic step between specialists of the different disciplines is warranted. In this retrospective study, we analyzed discrepant findings between imaging and pathology results on preoperative breast biopsies.

Methods

Core and vacuum-assisted breast biopsies from 232 patients were included in this study. Inclusion criteria were (1) non-diagnostic (B1) category on histology independent from imaging category and (2) histological benign (B2) category with a BIRADS 5 (Breast Imaging Reporting and Data System) rating on imaging. Histological diagnoses were retrieved from all cases. Follow-up data were available in most cases.

Results

138 biopsies were classified as B1, 94 biopsies as B2 category. 51 of 138 B1 cases (37%) underwent re-biopsy. Re-biopsy found malignancy (B5) in 19 of 51 cases, and B3/4 (premalignant) lesions in 3 of 51 cases. All B2 cases underwent second-look imaging-diagnosis, in 57 of 94 cases (66%) consecutive direct surgery or re-biopsy. Of these, malignancy was diagnosed histologically in 26 of 57 cases (45.6%).

Conclusion

Determining imaging-pathology concordance after US-guided breast biopsy is essential. Discrepant cases and further diagnostic steps need to be discussed with an interdisciplinary approach.

Role of ultrasound in predicting the molecular subtypes of invasive breast ductal carcinoma

Background

Breast cancer is a heterogeneous disease that was explained recently by the presence of multiple molecular subtypes. These subtypes are the luminal A (LA), luminal B (LB), human epidermal growth factor receptor 2 (HER2), and triple-negative (TN). In this study, we aim to investigate whether ultrasound imaging features can play a role in predicting the molecular subtypes of invasive ductal breast cancer (IDC) and to assess whether the nodal metastasis is an independent predictor for each subtype.

Results

The predictive sonographic signs for each subtype are as follows: echogenic halo, posterior shadowing, angular or spiculated margin, and unifocal mass for LA subtype; irregular shape for LB subtype; unifocal mass, abrupt interface of the tumor boundary, and posterior enhancement or no posterior change for HER2 subtype; and circumscribed or lobulated margin, oval or rounded shape, posterior enhancement or no posterior change, abrupt interface of the tumor boundary, and parallel orientation of the mass for TN. By multivariate logistic regression, presence of nodal metastasis is the strongest independent predictor for HER2 subtype, and its absence is the strongest independent predictor for LA subtype.

Conclusions

Certain sonographic signs are predictors for each molecular subtype of IDC. Nodal metastasis is an independent predictor for HER2 subtype when present and for LA subtype when absent.

The role of tissue elasticity in the differential diagnosis of benign and malignant breast lesions using shear wave elastography

Background

Elastography is a promising way to evaluate tissue differences regarding stiffness, and the stiffness of the malignant breast lesions increased at the lesion margin. However, there is a lack of data on the value of the shear wave elastography (SWE) parameters of the surrounding tissue (shell) of different diameter on the diagnosis of benign and malignant breast lesions. Therefore, the purpose of our study was to evaluate the diagnostic performance of shell elasticity in the diagnosis of benign and malignant breast lesions using SWE.

Methods

Between September 2016 and June 2017, women with breast lesions underwent both conventional ultrasound (US) and SWE. Elastic values of the lesions peripheral tissue were determined according to the shell size, which was automatically drawn along the edge of the lesion using the following software guidelines: (1): 1 mm; (2): 2 mm; and (3): 3 mm. Quantitative elastographic features of the inner lesions and shell, including the elasticity mean (E_mean), elasticity maximum (E_max), and elasticity minimum (E_min), were calculated using an online-available software. The receiver operating characteristic curves (ROCs) of the elastographic features was analyzed to assess the diagnostic performance, and the area under curve (AUC) of each elastographic feature was obtained. Logistic regression analysis was used to predict significant factors of malignancy, permitting the design of predictive models.

Results

This prospective study included 63 breast lesions of 63 women. Of the 63 lesions, 33 were malignant and 30 were benign. The diagnostic performance of E_max-3shell was the highest (AUC = 0.76) with a sensitivity of 60.6% and a specificity of 83.3%. According to stepwise logistic regression analysis, the E_max-3shell and the E_min-3shell were significant predictors of malignancy (p < 0.05). The AUC of the predictive equation was 0.86.

Conclusions

SWE features, particularly the combination of E_max-3shell and E_min-3shell can improve the diagnosis of breast lesions.

Non-mass lesions detected by breast US: stratification of cancer risk for clinical management

OBJECTIVE

To develop a classification system using imaging features to interpret breast non-mass lesions (NMLs) detected on US and to stratify their cancer risk.

METHODS

This retrospective study included 715 patients with 715 breast NMLs detected on breast US from 2012 to 2016. Each patient underwent mammography at the time of diagnosis. Radiologists assessed US and mammographic features and final BI-RADS categories. Multivariable logistic regression was used to find imaging features associated with malignancy in a development dataset (n = 460). A system to classify BI-RADS categories (3 to 5) was developed based on the odds ratios (ORs) of imaging features significantly associated with malignancy and validated in a distinct validation dataset (n = 255).

RESULTS

Among 715 NMLs, 385 (53.8%) were benign and 330 (46.2%) were malignant. In the development dataset, the following B-mode US features were associated with malignancy (all p < 0.001): segmental distribution (OR = 3.03; 95% confidence interval [CI], 1.50-6.15), associated calcifications (OR = 4.26; 95% CI, 1.62-11.18), abnormal ductal change (OR = 4.91; 95% CI, 2.07-11.68), and posterior shadowing (OR = 20.20; 95% CI, 6.46-63.23). The following mammographic features were also associated with malignancy (all p < 0.001): calcifications (OR = 7.98; 95% CI, 3.06-20.81) and focal asymmetry (OR = 4.75; 95% CI, 1.90-11.88). In the validation dataset, our classification system using US and mammography showed a higher area under the curve (0.951-0.956) compared to when it was not applied (0.908-0911) to predict malignancy with BI-RADS categories (p < 0.05).

CONCLUSION

Our classification system which incorporates US and mammographic features of breast NMLs can help interpret and manage all NMLs detected on breast US by stratifying cancer risk according to BI-RADS categories.

KEY POINTS

• When diagnosing breast NMLs detected on US, suspicious US features are segmental distribution, associated abnormal ductal change, calcifications, and posterior shadowing within or around the NML on B-mode US, while a probably benign US feature is the presence of multiple small cysts. • Corresponding suspicious mammographic features of breast NMLs detected on US are associated calcifications and focal asymmetry. • Our classification system which incorporates US features with and without mammography can potentially be used to interpret and manage any NMLs detected on breast US in clinical practice.

Triple metachronous primary cancer of uterus, colon, and breast cancer: A case report and review of the literature

RATIONALE

Triple or more primary malignancies are rare, with only 23 previous cases including breast cancer reported in the English language studies between January 1990 and December 2019.

PATIENT CONCERNS

The patient was a 67-year-old woman with a mass in her right breast. She had a previous history of uterine and colon cancer. Both ultrasonography and mammography revealed a Breast Imaging Reporting and Data System (BI-RADS) category 3 breast lesion, in which proliferative nodules are more likely. Given her previous history of 2 malignancies, her doctors strongly recommended a biopsy.

DIAGNOSIS AND INTERVENTIONS

The biopsy pathology suggested intraductal breast cancer. Mastectomy and sentinel lymph node biopsy were performed. The postoperative pathological diagnosis was invasive ductal carcinoma, grade II, stage I. The sample was positive for estrogen receptor and progesterone receptor and negative for cerbB-2. No radiotherapy or chemotherapy was administered except for endocrine therapy. A follow-up at 19 months showed no breast recurrence or distant metastases.

OUTCOMES

No recurrence or distant metastasis occurred within the 19-month, 11-year, and 20-year follow-ups for breast, colon, and uterine cancers, respectively.

LESSONS

To our knowledge, this is the first review of triple or more primary malignancies including breast cancer. These malignancies occur predominantly in older female patients. The most prevalent tumors of triple or more primary malignancies including breast cancer occur in the colon, uterus, and lung. A favorable prognosis is associated with early-stage malignancies.

Does contrast-enhanced ultrasound (CEUS) play a better role in diagnosis of breast lesions with calcification? A comparison with MRI

OBJECTIVE

To compare the efficacy of contrast-enhanced ultrasound enabled reclassification of Breast Imaging Reporting and Data System (CEUS-BI-RADS) with MRI in the diagnosis of breast lesions with calcification.

METHODS

A total of 52 breast lesions with calcification from 51 patients were detected by ultrasound as hyperechoic foci and categorized as BI-RADS 3-5. The 51 patients further underwent CEUS scan and MRI. The ultrasound-BI-RADS combined with CEUS 5-point score system redefined the classification of BI-RADS which was called CEUS-BI-RADS. The diagnostic efficacy of three methods was assessed by receiver operating characteristic (ROC) curve analysis. Histopathological assessment used as the gold-standard.

RESULTS

The sensitivities of Ultrasound-BI-RADS, MRI classification of BI-RADS (MRI-BI-RADS) and CEUS-BI-RADS were 85%, 90% and 95% without significant difference among the three modalities (p > 0.05). The diagnostic specificities of ultrasound-BI-RADS, MRI-BI-RADS and CEUS-BI-RADS were 78.1%, 78.1% and 96.8%, respectively (p < 0.05); and the accuracy were 80.7%, 82.6% and 96.1% for ultrasound-BI-RADS, MRI-BI-RADS and CEUS-BI-RADS, respectively (p < 0.05). The area under ROC (AUROC) in differentiation of breast lesions with calcification was 0.945 for CEUS-BI-RADS, 0.907 for MRI-BI-RADS and 0.853 for ultrasound-BI-RADS, with no significant difference among the three modalities (p > 0.05).

CONCLUSION

The CEUS-BI-RADS has a better diagnostic efficiency than MRI-BI-RADS in the differentiation of the breast lesions with calcification.

ADVANCES IN KNOWLEDGE

•CEUS is a better method in differentiation of breast lesions with calcification.•CEUS-BI-RADS increases the efficiency of diagnosis compared to MRI.

Evaluation of the predictive ability of ultrasound-based assessment of breast cancer using BI-RADS natural language reporting against commercial transcriptome-based tests

Purpose

The objective of this study was to assess the classification capability of Breast Imaging Reporting and Data System (BI-RADS) ultrasound feature descriptors targeting established commercial transcriptomic gene signatures that guide management of breast cancer.

Materials and methods

This retrospective, single-institution analysis of 219 patients involved two cohorts using one of two FDA approved transcriptome-based tests that were performed as part of the clinical care of breast cancer patients at Harbor-UCLA Medical Center between April 2008 and January 2013. BI-RADS descriptive terminology was collected from the corresponding ultrasound reports for each patient in conjunction with transcriptomic test results. Recursive partitioning and regression trees were used to test and validate classification of the two cohorts.

Results

The area under the curve (AUC) of the receiver operator curves (ROC) for the regression classifier between the two FDA approved tests and ultrasound features were 0.77 and 0.65, respectively; they employed the ‘margins’, ‘retrotumoral’, and ‘internal echoes’ feature descriptors. Notably, the ‘retrotumoral’ and mass ‘margins’ features were used in both classification trees. The identification of sonographic correlates of gene tests provides added value to the ultrasound exam without incurring additional procedures or testing.

Conclusions

The predictive capability using structured language from diagnostic ultrasound reports (BI-RADS) was moderate for the two tests, and provides added value from ultrasound imaging without incurring any additional costs. Incorporation of additional measures, such as ultrasound contrast enhancement, with validation in larger, prospective studies may further substantiate these results and potentially demonstrate even greater predictive utility.

Application of Point Shearwave Elastography to Breast Ultrasonography: Initial Experience Using “S-Shearwave” in Differential Diagnosis

Purpose

To evaluate the optimal measurement location, cut-off value, and diagnostic performance of S-Shearwave in differential diagnosis of breast masses seen on ultrasonography (US).

Materials and Methods

During the study period, 225 breast masses in 197 women were included. S-Shearwave measurements were made by applying a square region-of-interest automatically generated by the US machine. Shearwave elasticity was measured three times at four different locations of the mass, and the highest shearwave elasticity was used for calculating the optimal cut-off value. Diagnostic performance was evaluated by using the area under the receiving operator characteristic curve (AUC).

Results

Of the 225 breast masses, 156 (69.3%) were benign and 69 (30.7%) were malignant. Mean S-Shearwave values were significantly higher for malignant masses (108.0 ± 70.0 kPa vs. 43.4 ± 38.3 kPa; p < 0.001). No significant differences were seen among AUC values at different measurement locations. With a cut-off value of 41.9 kPa, S-Shearwave showed 85.7% sensitivity, 63.9% specificity, 70.7% accuracy, and positive and negative predictive values of 51.7% and 90.8%, respectively. The AUCs for US and S-Shearwave did not show significant differences (p = 0.179).

Conclusion

S-Shearwave shows comparable diagnostic performance to that of grayscale US that can be applied for differential diagnosis of breast masses seen on US.

Effect of a Deep Learning Framework-Based Computer-Aided Diagnosis System on the Diagnostic Performance of Radiologists in Differentiating between Malignant and Benign Masses on Breast Ultrasonography

OBJECTIVE

To investigate whether a computer-aided diagnosis (CAD) system based on a deep learning framework (deep learning-based CAD) improves the diagnostic performance of radiologists in differentiating between malignant and benign masses on breast ultrasound (US).

MATERIALS AND METHODS

B-mode US images were prospectively obtained for 253 breast masses (173 benign, 80 malignant) in 226 consecutive patients. Breast mass US findings were retrospectively analyzed by deep learning-based CAD and four radiologists. In predicting malignancy, the CAD results were dichotomized (possibly benign vs. possibly malignant). The radiologists independently assessed Breast Imaging Reporting and Data System final assessments for two datasets (US images alone or with CAD). For each dataset, the radiologists' final assessments were classified as positive (category 4a or higher) and negative (category 3 or lower). The diagnostic performances of the radiologists for the two datasets (US alone vs. US with CAD) were compared.

RESULTS

When the CAD results were added to the US images, the radiologists showed significant improvement in specificity (range of all radiologists for US alone vs. US with CAD: 72.8-92.5% vs. 82.1-93.1%; p < 0.001), accuracy (77.9-88.9% vs. 86.2-90.9%; p = 0.038), and positive predictive value (PPV) (60.2-83.3% vs. 70.4-85.2%; p = 0.001). However, there were no significant changes in sensitivity (81.3-88.8% vs. 86.3-95.0%; p = 0.120) and negative predictive value (91.4-93.5% vs. 92.9-97.3%; p = 0.259).

CONCLUSION

Deep learning-based CAD could improve radiologists' diagnostic performance by increasing their specificity, accuracy, and PPV in differentiating between malignant and benign masses on breast US.

Evaluation of the positive predictive value (PPV3) of ACR BI-RADS category 4 and 5 based on the outcomes of Invasive Diagnostic Office in an outpatient clinic

PURPOSE

The American College of Radiology (ACR) BI-RADS classification is the applicable for breast lesion assessment. BI-RADS categories 4 and 5 need to be followed by biopsy. The aim of our study was to evaluate the tissue biopsy-proven positive predictive value (PPV3) for BI-RADS 4 (and its subcategories) and for BI-RADS 5, and BI-RADS distribution, in comparison to ACR assumptions and literature.

MATERIAL AND METHODS

We retrospectively analysed biopsies performed in our outpatient clinic in 2017. Our target group of patients consisted of 797 patients at the average age of 52 years.

RESULTS

BI-RADS 5 constituted 12% of cases (95 cases), and BI-RADS 4 88% (698 cases). Within BI-RADS 4 subdivisions there were 359 cases in 4a (45.3%), 215 in 4b (27%), and 124 in 4c (15.6%). Overall PPV3 was 34.8%. BI-RADS 5 category PPV3 number was 97.89%. In category BI-RADS 4 the values of PPV3 equalled 26.22% without subdivision and 3.6%, 27.9%, and 88.7% for subcategories BI-RADS 4a, 4b, and 4c, respectively.

CONCLUSIONS

BI-RADS categorisation by radiologists in the studied group matches the literature data according to achieved PPV and BI-RADS percentage distribution. The stratification of cancer risk among categories was proven with Mann-Whitney U test p value < 0.005. There was a statistically important unaccepted difference of PPV3 between core biopsy and vacuum-assisted biopsy, which needs further investigation.

A preliminary study to propose a diagnostic algorithm for PET/CT-detected incidental breast lesions: application of BI-RADS lexicon for US in combination with SUVmax

OBJECTIVES

To develop a diagnostic algorithm for positron emission tomography (PET)-detected incidental breast lesions using both breast imaging reporting and data system (BI-RADS) and maximum standardized uptake value (SUVmax) criteria.

METHODS

Fifty-six PET-detected incidental breast lesions from 51 patients, which were subsequently investigated by breast ultrasound within 1 month of the PET study, constituted the study cohort and they were finally verified by tissue diagnosis or a 2-year follow-up. Based on the maximum specificity with sensitivity > 60.0% and maximum sensitivity with specificity > 60.0%, two SUVmax cutoff values were calculated at 2 and 3.7. BI-RADS ≥ 4 was considered as highly suspicious for malignancy. The diagnostic accuracies were estimated for SUVmax levels above or below the cutoff points combined with the BI-RADS suspicion level.

RESULTS

Overall, 46 benign and 10 malignant lesions were studied. The diagnostic characteristics of SUVmax ≥ 2, SUVmax ≥ 3.7, and BI-RADS ≥ 4 were 80.0%, 60.0%, and 80.0% for sensitivity, 73.9%, 95.7%, and 92.7% for specificity, and 75.0%, 89.3%, and 90.2% for accuracy, respectively. When the SUVmax threshold was set at 2, combined with BI-RADS suspicion level, the sensitivity, specificity, and accuracy were 100.0%, 69.6%, and 75.0%, respectively. The results for SUVmax threshold set at 3.7 combined with BI-RADS were 90.0%, 91.3%, and 91.1% for the sensitivity, specificity, and accuracy, respectively. A diagnostic algorithm was accordingly generated.

CONCLUSION

The need for biopsy should be justified in low BI-RADS lesions presenting with high SUVmax at 3.7 or higher. The biopsy of patients with high B-IRADS and low SUVmax could be preserved.

KEY POINTS

• A diagnostic algorithm was developed for PET-detected incidental breast lesions using both BI-RADS and SUVmax criteria. • Diagnostic performance was calculated separately and conjunctively for SUVmax ≥ 2, SUVmax ≥ 3.7, and BI-RADS ≥ 4. • The need for biopsy can be justified in BI-RADS < 4 lesions with SUVmax ≥ 3.7. Lesions with BI-RADS < 4 and indeterminate SUVmax (2 < SUVmax < 3.7) benefit from a short-interval follow-up. BI-RADS < 4 lesions with SUVmax < 2 may confidently be scheduled for routine screening.

Role of elastography for downgrading BI-RADS category 4a breast lesions according to risk factors

BACKGROUND

Elastography has been introduced as an additional diagnostic tool to ultrasonography (US) which helps clinicians decide whether or not to perform biopsy on US-detected lesions.

PURPOSE

To evaluate the role of strain elastography in downgrading Breast Imaging Reporting and Data System (BI-RADS) category 4a breast lesions according to personal risk factors for breast cancer in asymptomatic women.

MATERIAL AND METHODS

Strain elastography features of a total of 255 asymptomatic category 4a lesions were classified as soft and not soft (intermediate and hard). Malignancy was confirmed by surgery or biopsy, and benignity was confirmed by surgery or biopsy with no change on US for at least six months. Malignancy rates of lesions with soft and not soft elastography were calculated according to the presence of risk factors.

RESULTS

Of 255 lesions, 25 (9.8%) were malignant and 230 (90.2%) were benign. Of 195 lesions in average-risk women, the malignancy rate of lesions with soft elastography was 1.5% (1/68), which was significantly lower than the 14.2% (18/127) of lesions with not soft elastography ( P = 0.004). Of 60 lesions in increased-risk women, the malignancy rate of lesions with soft elastography was 15.0% (3/20), which was not significantly different from the 7.5% (3/40) of lesions with not soft elastography ( P = 0.390).

CONCLUSION

In average-risk women, category 4a lesions with soft elastography could be followed up with US because of a low malignancy rate of 1.5%.

Probably Benign Solid Breast Lesions on Ultrasound: Need for Biopsy Reassessed

Objective:

To determine the negative predictive value of ultrasound for breast masses with probably benign morphology, and to assess whether follow-up may be an acceptable alternative to biopsy.

Methods:

After Institutional Review Board approval, all solid breast masses categorized as probably benign (American College of Radiology Breast Imaging Reporting and Data System [BI-RADS] 3) on ultrasound from January 2014 to December 2015, and having either tissue diagnosis or imaging stability for 24 months, or downgrading to BIRADS 2 during imaging surveillance were included.

Result:

A total of 157 lesions in 40 patients constituted the study population. The mean patient age was 31.3 years (range, 20-56 years). Seventeen of these 157 lesions underwent tissue diagnosis with no invasive breast cancer. Out of the remaining 140 lesions, 115 were stable on imaging for 24 months or more. The rest 25 were deemed benign because of decrease in size on follow up (n=1), non-recommendation of further imaging by the second radiologist on follow up ultrasound (n= 13) or presence of benign tissue diagnosis in the largest lesion (n=11).

Conclusion:

Ultrasound has 100% negative predictive value for breast lesions with probably benign morphology, whether palpable or not. Follow up is an appropriate option to immediate biopsy of such lesions keeping in mind that noncompliance with surveillance may be a potential problem.

Breast Imaging Reporting and Data Systems category 3 (probably benign) breast lesions detected on diagnostic breast ultrasound: The prevalence, outcome and malignancy detection rate in Zaria, Nigeria

Background

Probably benign breast lesions in the Breast Imaging Reporting and Data Systems (BI-RADS 3) constitute a crucial category and a considerable number of all palpable breast masses. Local data concerning the outcome of such lesions in the Nigerian environment is almost non-existent.

Objectives

The goal of this article is to report the frequency, outcome and malignancy detection rate among palpable breast masses that were categorised on ultrasound as BI-RADS category 3 (probably benign) according to the American College of Radiology (ACR).

Methods

Between January 2015 and July 2017, 603 patients had diagnostic whole-breast ultrasound scans. There were 277 women who complained of palpable breast masses, of whom 151 women were diagnosed as having BI-RADS 3 lesions. The final lesion outcome was determined by either biopsy or ultrasound follow-up examination for a total of 2 years. All data were recorded and analysed with Statistical Package for the Social Sciences (SPSS) version 20 (Chicago, USA).

Results

The frequency of BI-RADS category 3 lesions among all the women who underwent breast ultrasound was 25% (151/603); and 54% (151/277) in patients with palpable breast masses. There were 25 patients who were excluded because of incomplete data or who were lost to follow-up. A total of 122 patients had both ultrasound examination and histopathologic diagnosis, while only 4 were followed up for 2 years on ultrasound alone. Of the 122 women biopsied, 117 (95.9%) had benign histologic outcomes, and of the remaining 5, cancer was confirmed in 2 (1.6%), while the remaining 3 patients (2.5%) had lesions considered intermediate at histology (juvenile papillomatosis, borderline phylloides and atypical ductal hyperplasia). Three out of four patients who had ultrasound follow-up alone had stable lesions after 2 years, while one patient had complete resolution.

Conclusion

This study found a significantly high biopsy rate of 80% (122/151) for probably benign lesions but a low detection rate for malignancy (1.6%). Follow-up with imaging rather than biopsy for lesions sonographically described as probably benign, will reduce medical costs and unwarranted invasive procedures.

Length Scale Matters: Real-Time Elastography versus Nanomechanical Profiling by Atomic Force Microscopy for the Diagnosis of Breast Lesions

Real-time elastography (RTE) is a noninvasive imaging modality where tumor-associated changes in tissue architecture are recognized as increased stiffness of the lesion compared to surrounding normal tissue. In contrast to this macroscopic appraisal, quantifying stiffness properties at the subcellular level by atomic force microscopy (AFM) reveals aggressive cancer cells to be soft. We compared RTE and AFM profiling of the same breast lesion to explore the diagnostic potential of tissue elasticity at different length scales. Patients were recruited from women who were scheduled for a biopsy in the outpatient breast clinic of the University Hospital Basel, Switzerland. RTE was performed as part of a standard breast work-up. Individual elastograms were characterized based on the Tsukuba elasticity score. Additionally, lesion elasticity was semiquantitatively assessed by the strain ratio. Core biopsies were obtained for histologic diagnosis and nanomechanical profiling by AFM under near-physiological conditions. Bulk stiffness evaluation by RTE does not always allow for a clear distinction between benign and malignant lesions and may result in the false assessment of breast lesions. AFM on the other hand enables quantitative stiffness measurements at higher spatial, i.e., subcellular, and force resolution. Consequently, lesions that were false positive or false negative by RTE were correctly identified by their nanomechanical AFM profiles as confirmed by histological diagnosis. Nanomechanical measurements can be used as unique markers of benign and cancerous breast lesions by providing relevant information at the molecular level. This is of particular significance considering the heterogeneity of tumors and may improve diagnostic accuracy compared to RTE.

The added value of contrast-enhanced ultrasound to conventional ultrasound in differentiating benign and malignant solid breast lesions: a systematic review and meta-analysis

AIM

To investigate the added value of contrast-enhanced ultrasound (CEUS) to the conventional ultrasound (US) in the diagnosis of breast lesions.

MATERIALS AND METHODS

PubMed, EMBASE, and Web of Science were searched for relevant studies published between 24 May 2005, and 29 October 2017. Studies incorporating CEUS into the conventional US were included. The reference standard was set by means of histopathological findings. The quality assessment of diagnostic studies (QUADAS) instrument was used to assess the quality of the included studies. Meta-Disc version 1.4. was used to calculate the sensitivity, specificity, summary receiver-operating characteristic (sROC) curves, and area under the curve (AUC). Meta-regression with Stata 12.0 was used to compare the diagnostic accuracy of the two techniques.

RESULTS

Five studies, comprising 992 patients, were eligible for this meta-analysis. For conventional US, the pooled sensitivity and specificity for were 0.87 (95% confidence interval [CI]: 0.84-0.91) and 0.80 (95% CI: 0.76-0.84), respectively, the AUC was 0.9049. For CEUS-rerated US, the pooled sensitivity and specificity were 0.93 (95% CI: 0.90-0.95) and 0.87 (95% CI: 0.84-0.90). The AUC was 0.9482. Meta-regression showed the sensitivity of CEUS-rerated US did not differ from conventional US (p=0.29), while specificity showed significant difference (p<0.01). There was evidence of between-study heterogeneity regarding sensitivity and specificity for both assessments.

CONCLUSIONS

Adding CEUS to conventional US could improve the diagnostic performance in differentiating benign from malignant solid breast lesions, whilst retaining high sensitivity, especially in Breast Imaging-Reporting and Data System (BI-RADS) 3-5 lesions. A uniform standard to distinguish benign from malignant lesions might be needed for further clinical application.

Interobserver agreement in breast ultrasound categorization in the Mammography and Ultrasonography Study for Breast Cancer Screening Effectiveness (MUST-BE) trial: results of a preliminary study

Purpose

The purpose of this study was to record and evaluate interobserver agreement as quality control for the modified categorization of screening breast ultrasound developed by the Alliance for Breast Cancer Screening in Korea (ABCS-K) for the Mammography and Ultrasonography Study for Breast Cancer Screening Effectiveness (MUST-BE) trial.

Methods

Eight breast radiologists with 4-16 years of experience participated in 2 rounds of quality control testing for the MUST-BE trial. Two investigators randomly selected 125 and 100 cases of breast lesions with different ratios of malignant and benign lesions. Two versions of the modified categorization were tested. The initially modified classification was developed after the first quality control workshop, and the re-modified classification was developed after the second workshop. The re-modified categorization established by ABCS-K added size criteria and the anterior-posterior ratio compared with the initially modified classification. After a brief lecture on the modified categorization system prior to each quality control test, the eight radiologists independently categorized the lesions using the modified categorization. Interobserver agreement was measured using kappa statistics.

Results

The overall kappa values for the modified categorizations indicated moderate to substantial degrees of agreement (initially modified categorization and re-modified categorization: κ=0.52 and κ=0.63, respectively). The kappa values for the subcategories of category 4 were 0.37 (95% confidence interval [CI], 0.24 to 0.52) and 0.39 (95% CI, 0.31 to 0.49), respectively. The overall kappa values for both the initially modified categorization and the re-modified categorization indicated a substantial degree of agreement when dichotomizing the interpretation as benign or suspicious.

Conclusion

The preliminary results demonstrated acceptable interobserver agreement for the modified categorization.

Follow-up interval for probably benign breast lesions on screening ultrasound in women at average risk for breast cancer with dense breasts

Background Women at high risk for breast cancer and women at average risk have different pretest probabilities. Probably benign lesions on screening ultrasound (US) should be assessed and managed differently for these two risk groups. Purpose To evaluate the effectiveness of short-term follow-up for probably benign lesions on screening US in women at average risk for breast cancer with dense breasts. Material and Methods A total of 445 women at average risk for breast cancer with probably benign lesions on screening US, dense breasts, and negative or benign mammography results were included. Women were classified into the six-month group (n = 345) or 12-month group (n = 100) according to when the first follow-up was performed (3-9 months or 9-15 months). The cancer detection rate, frequencies of newly developed lesions and progressed lesions, and biopsy rate were compared. Results There were no malignancies from three to 15 months. Three cancers newly developed after 15 months. One was a 3-mm ductal carcinoma in situ and two were 10-mm and 18-mm invasive ductal carcinoma without lymph node metastasis. The frequency of newly developed lesions and progressed lesions and biopsy rate were not significantly different between the six-month and 12-month groups ( P = 0.320, 0.621, and >0.999). Conclusion A follow-up at 12 months can be considered for probably benign lesions on screening US in women at average risk for breast cancer with dense breasts. However, a large series prospective study is needed before clinical application.

Growing BI-RADS category 3 lesions on follow-up breast ultrasound: malignancy rates and worrisome features

OBJECTIVE

  To determine the frequency and malignancy rate among growing Breast Imaging Reporting and Data System (BI-RADS) category 3 lesions diagnosed on follow-up breast ultrasound and to evaluate the radiological and clinical features associated with malignancy.  Methods:  Of the 38,482 women who underwent breast ultrasound between January 2010 and December 2011, 11,582 (30.1%) patients had 12,514 BI-RADS category 3 lesions. Patients whose lesions showed ≥20% enlargement on follow-up ultrasound were selected for this study. Radiological and clinical features including increase in the maximum diameter and anteroposterior dimension, morphological changes determined via ultrasound, palpability, multiplicity, new mass, baseline breast ultrasound indication and mammographic BI-RADS category were evaluated to determine their association with malignancy. Multivariate analyses were used to identify independent predictors of malignancy.  Results:  The frequency of growing BI-RADS category 3 lesions on follow-up ultrasound was 5.9% (738 of 12,514). Of 527 lesions examined in 459 patients with a follow-up duration of at least 24 months or with available pathological results, 26 proved to be malignant (4.9%). Multivariate analyses further indicated that sonographic morphological changes (OR, 7.662, p < 0.001) and development of suspicious features on follow-up mammography (OR, 3.812, p = 0.009) were associated with malignancy. Enlargement without associated suspicious mammography or sonographic morphological abnormalities had only 1.9 % (BI-RADS category 3) chance of malignancy.  Conclusion:  The malignancy rate for growing BI-RADS category 3 lesions is 4.9%. Sonographic morphological changes and suspicious mammographic features in these tumors are significantly associated with malignancy. Advances in knowledge: For lesions with an interval growth in the anteroposterior dimension of ≤50% without morphological changes, together with a benign mammogram, follow-up rather than an immediate biopsy can be recommended to reduce false-positive biopsy results. The risk of malignancy in lesions with a size increment but with no morphologic change on sonography is only 1.9%, compatible with continued BI-RADS category 3 classification.

Diagnostic performances of supplemental breast ultrasound screening in women with personal history of breast cancer

Background Supplemental breast ultrasonography (US) has been used as a surveillance imaging method in women with personal history of breast cancer (PHBC). However, there have been limited data regarding diagnostic performances. Purpose To evaluate diagnostic performances of supplemental breast US screening for women with PHBC and to compare with those for women without PHBC. Material and Methods Between 2011 and 2012, 12,230 supplemental US exams were performed in 12,230 women with negative mammograms: 6584 women with PHBC and 5646 women without PHBC. Cancer detection rate, interval cancer rate, abnormal interpretation rate, positive predictive values (PPVs), sensitivity, and specificity were calculated and compared. Results Overall cancer detection rate and first-year interval cancer rate were 1.80/1000 exams and 0.91/1000 negative exams, both of which were higher in women with PHBC than in women without PHBC (2.88 vs. 0.53 per 1000, P = 0.003; 1.50 vs. 0.20 per 1000, P = 0.027). Abnormal interpretation rate was lower in the women with PHBC than in women without PHBC (9.1% vs. 12.1%, P < 0.001). Sensitivity was not different (67.9% vs. 75.0%, P = 1.000), whereas specificity and PPV₃ were higher in women with PHBC than in women without PHBC (91.2% vs. 88.0%, P < 0.001; 22.6% vs. 3.1%, P < 0.001). The majority of detected cancers in women with PHBC (78.9%, 15/19) were stage 0 or 1. Conclusion Supplemental breast US screening increases early stage second breast cancers with high specificity and PPV₃ in women with PHBC, however, high interval cancer rate in younger women with PHBC should be noted.

A case-oriented web-based training system for breast cancer diagnosis

BACKGROUND AND OBJECTIVE

Breast cancer is still considered as the most common form of cancer as well as the leading causes of cancer deaths among women all over the world. We aim to provide a web-based breast ultrasound database for online training inexperienced radiologists and giving computer-assisted diagnostic information for detection and classification of the breast tumor.

METHODS

We introduce a web database which stores breast ultrasound images from breast cancer patients as well as their diagnostic information. A web-based training system using a feature scoring scheme based on Breast Imaging Reporting and Data System (BI-RADS) US lexicon was designed. A computer-aided diagnosis (CAD) subsystem was developed to assist the radiologists to make scores on the BI-RADS features for an input case. The training system possesses 1669 scored cases, where 412 cases are benign and 1257 cases are malignant. It was tested by 31 users including 12 interns, 11 junior radiologists, and 8 experienced senior radiologists.

RESULTS

This online training system automatically creates case-based exercises to train and guide the newly employed or resident radiologists for the diagnosis of breast cancer using breast ultrasound images based on the BI-RADS. After the trainings, the interns and junior radiologists show significant improvement in the diagnosis of the breast tumor with ultrasound imaging (p-value < .05); meanwhile the senior radiologists show little improvement (p-value > .05).

CONCLUSIONS

The online training system can improve the capabilities of early-career radiologists in distinguishing between the benign and malignant lesions and reduce the misdiagnosis of breast cancer in a quick, convenient and effective manner.

Evaluating imaging-pathology concordance and discordance after ultrasound-guided breast biopsy

Ultrasound (US)-guided breast biopsy has become the main method for diagnosing breast pathology, and it has a high diagnostic accuracy, approaching that of open surgical biopsy. However, methods for confirming adequate lesion retrieval after US-guided biopsy are relatively limited and false-negative results are unavoidable. Determining imaging-pathology concordance after US-guided biopsy is essential for validating the biopsy result and providing appropriate management. In this review article, we briefly present the results of US-guided breast biopsy; describe general aspects to consider when establishing imaging-pathology concordance; and review the various categories of imaging-pathology correlations and corresponding management strategies.

Combination of shear-wave elastography and color Doppler: Feasible method to avoid unnecessary breast excision of fibroepithelial lesions diagnosed by core needle biopsy

Background

We evaluated shear-wave elastography (SWE) and color Doppler ultrasonography (US) features for fibroepithelial lesions (FELs), and to evaluate their utility to differentiate fibroadenomas (FAs) and phyllodes tumors (PTs).

Methods

This retrospective study included 67 FELs pathologically confirmed (49 FAs, 18 PTs). B-mode US, SWE and color Doppler US were performed for each lesion. Mean elasticity (E_mean), maximum elasticity (E_max), and vascularity were determined by SWE and Doppler US. Diagnostic performances were calculated to differentiate FAs and PTs. Equivocal FELs diagnosed by core needle biopsy (CNB) were further analyzed.

Results

Median E_mean and E_max were significantly lower for FAs than PTs (E_mean, 15.7 vs. 66.7 kPa; E_max, 21.0 vs. 76.7 kPa, P<0.01). Low vascularity (0–1 vessel flow) on color Doppler US were more frequent in FAs than in PTs (P<0.01). SWE showed significantly higher specificities (E_mean >43.9 kPa, 89.8%; E_max >46.1 kPa, 79.6%) than B-mode US (42.9%) (P<0.01) for differentiating PTs from FAs. Other diagnostic values of SWE and overall diagnostic values of Doppler US were not significantly different from B-mode US (P>0.05). The combination of SWE and Doppler US with ‘E_mean>43.9 kPa or high vascularity (≥2 vessel flows)’ showed a higher area under the curve (0.786 vs. 0.687) and higher diagnostic values than B-mode US (sensitivity, 100 vs. 94.4%; specificity, 57.1 vs. 42.9%; positive predictive value, 46.2 vs. 37.8%; negative predictive value, 100 vs. 95.5%), without statistical significance (P>0.05). Of the 30 equivocal FELs, all lesions with ‘E_mean≤43.9 kPa and low vascularity (0–1 vessel flow)’ (23.3%, 7/30) were finally confirmed as FAs by excision.

Conclusion

FAs have a tendency to have less stiffness and lower vascularity than PTs. Combined SWE and color Doppler US may help patients with equivocal FELs diagnosed by CNB avoid unnecessary excision.

First ultrasound diagnosis of BI-RADS 3 lesions in young patients: Can 6-months follow-up be sufficient to assess stability?

OBJECTIVES

To evaluate the outcome of repeated short-term follow-up with ultrasound in no high-risk young patients with a BI-RADS3 lesion at first examination.

METHODS

In this IRB-approved study 492 women, aged 18-34 years (mean±standard deviation, 28±4.5years) with first breast ultrasound examination in 2012-2014 were retrospectively evaluated. Inclusion criteria were: at least one BI-RADS3 lesion and (a) biopsy/surgical excision or (b) follow-up of at least 18 months (including a 6-month follow-up). BI-RADS category assigned during follow-up and pathologic findings in cases undergoing biopsy/surgical excision were collected. At the 6- and 18-month follow-up the recommended biopsy rates (RBR) and the corresponding positive predictive value (PPV) were calculated.

RESULTS

In 97 patients, 151 BI-RADS3 lesions were identified. Biopsy/surgical excision was initially performed in 25/151 (16.5%) lesions. After 6-month, category was downgraded to BI-RADS1/2 in 23/126 (15.3%) and upgraded to BI-RADS4 in 9/126 lesions (7.1%). Pathological diagnosis of these lesions was fibroadenoma in 5 and benign phyllodes tumor in 4 cases (RBR 7%, PPV_bio 44.4%). After 18-month one lesion was classified BI-RADS4 and pathological diagnosis was fibroadenoma (RBR 1.1%, PPV_bio 0%).

CONCLUSIONS

Our preliminary data show that follow-up imaging performed after 18 months from a first BI-RADS3 diagnosis does not affect clinical treatment and 6-month follow-up may be sufficient to assess the stability of probably benign lesions.

Application of 3D and 2D quantitative shear wave elastography (SWE) to differentiate between benign and malignant breast masses

As breast cancer tissues are stiffer than normal tissues, shear wave elastography (SWE) can locally quantify tissue stiffness and provide histological information. Moreover, tissue stiffness can be observed on three-dimensional (3D) colour-coded elasticity maps. Our objective was to evaluate the diagnostic performances of quantitative features in differentiating breast masses by two-dimensional (2D) and 3D SWE. Two hundred ten consecutive women with 210 breast masses were examined with B-mode ultrasound (US) and SWE. Quantitative features of 3D and 2D SWE were assessed, including elastic modulus standard deviation (E_SD^E) measured on SWE mode images and E_SD^U measured on B-mode images, as well as maximum elasticity (E_max). Adding quantitative features to B-mode US improved the diagnostic performance (p < 0.05) and reduced false-positive biopsies (p < 0.0001). The area under the receiver operating characteristic curve (AUC) of 3D SWE was similar to that of 2D SWE for E_SD^E (p = 0.026) and E_SD^U (p = 0.159) but inferior to that of 2D SWE for E_max (p = 0.002). Compared with E_SD^U, E_SD^E showed a higher AUC on 2D (p = 0.0038) and 3D SWE (p = 0.0057). Our study indicates that quantitative features of 3D and 2D SWE can significantly improve the diagnostic performance of B-mode US, especially 3D SWE E_SD^E, which shows considerable clinical value.

Incorporating Contrast-Enhanced Ultrasound into the BI-RADS Scoring System Improves Accuracy in Breast Tumor Diagnosis: A Preliminary Study in China

The aim of the study was to develop a scoring model incorporating the Breast Imaging Reporting and Data System (BI-RADS) and the contrast-enhanced ultrasound (CEUS) scoring system to differentiate between malignant and benign breast lesions. A total of 524 solid breast masses in 490 consecutive patients were evaluated with conventional US and CEUS in this prospective study. Each lesion was scored according to BI-RADS, CEUS, and CEUS-rerated BI-RADS. The diagnostic specificity, sensitivity and accuracy of BI-RADS were 77.9%, 88.9% and 84.0%, respectively, and the area under the receiver operating characteristic curve was 0.834. The corresponding values for rerated BI-RADS were 82.1%, 96.9%, 90.3% and 0.895. The area under the receiver operating characteristic curve of BI-RADS alone was significantly smaller than that of CEUS and the rerated BI-RADS (p = 0.008 compared with CEUS, p = 0.002 compared with rerated BI-RADS). This study indicates that rerating BI-RADS with the CEUS scoring system improves its diagnostic accuracy.

Which supplementary imaging modality should be used for breast ultrasonography? Comparison of the diagnostic performance of elastography and computer-aided diagnosis

Purpose

The aim of this study was to evaluate and compare the diagnostic performance of grayscale ultrasonography (US), US elastography, and US computer-aided diagnosis (US-CAD) in the differential diagnosis of breast masses.

Methods

A total of 193 breast masses in 175 consecutive women (mean age, 46.4 years) from June to August 2015 were included. US and elastography images were obtained and recorded. A US-CAD system was applied to the grayscale sonograms, which were automatically analyzed and visualized in order to generate a final assessment. The final assessments of breast masses were based on the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) categories, while elasticity scores were assigned using a 5-point scoring system. The diagnostic performance of grayscale US, elastography, and US-CAD was calculated and compared.

Results

Of the 193 breast masses, 120 (62.2%) were benign and 73 (37.8%) were malignant. Breast masses had significantly higher rates of malignancy in BI-RADS categories 4c and 5, elastography patterns 4 and 5, and when the US-CAD assessment was possibly malignant (all P<0.001). Elastography had higher specificity (40.8%, P=0.042) than grayscale US. US-CAD showed the highest specificity (67.5%), positive predictive value (PPV) (61.4%), accuracy (74.1%), and area under the curve (AUC) (0.762, all P<0.05) among the three diagnostic tools.

Conclusion

US-CAD had higher values for specificity, PPV, accuracy, and AUC than grayscale US or elastography. Computer-based analysis based on the morphologic features of US may be very useful in improving the diagnostic performance of breast US.

Reliability of Breast Ultrasound BI-RADS Final Assessment in Mammographically Negative Patients with Nipple Discharge and Radiologic Predictors of Malignancy

Purpose

The purpose of this study was to retrospectively investigate the reliability of breast ultrasound (US) Breast Imaging Reporting and Data System (BI-RADS) final assessment in mammographically negative patients with pathologic nipple discharge, and to determine the clinical and ultrasonographic variables associated with malignancy in this group of patients.

Methods

A total of 65 patients with 67 mammographically negative breast lesions that were pathologically confirmed through US-guided biopsy were included.

Results

Of the 53 BI-RADS category 4 and 5 lesions, eight (15.1%) were malignant (six ductal carcinomas in situ, one invasive ductal carcinoma, and one solid papillary carcinoma). There was no malignancy among the remaining 14 category 3 lesions. Malignant lesions more frequently displayed a round or irregular shape (75.0%, 6/8; p=0.030) and nonparallel orientation (33.3%, 4/12; p=0.029) compared to the benign lesions. The increase in the BI-RADS category corresponded with a rise in the malignancy rate (p=0.004).

Conclusion

The BI-RADS lexicon and final assessment of breast US reliably detect and characterize malignancy in mammographically negative patients with pathologic nipple discharge.

Assessment of Diagnostic Accuracy and Efficiency of Categories 4 and 5 of the Second Edition of the BI-RADS Ultrasound Lexicon in Diagnosing Breast Lesions

The purpose of this study was to evaluate the diagnostic accuracy and efficiency of categories 4 and 5 of the second edition of the Breast Imaging Reporting and Data System (BI-RADS) ultrasound (US) lexicon in diagnosing breast lesions. In our retrospective study, 579 lesions in 544 patients were assessed by US as the preliminary diagnosis and classified in subcategories 4a-4c and category 5 based on the second edition of the BI-RADS US lexicon with some obvious changes, such as the redefined margin, new calcification type, associated features and some special cases. Inter-observer agreement was determined. Ultrasound results were compared with the pathologic results for confirmation. Positive predictive values (PPVs) of subcategories 4a-4c were compared with theoretical values using the χ(2) test; the binomial test was used for category 5 lesions. Of the 579 lesions, 212 were confirmed as benign (36.61%), and the remaining 367 lesions were confirmed as borderline/malignant (63.39%). Inter-observer agreement was moderate for subcategories 4a-4c (κ = 0.52), moderate for subcategories 4a-4c and category 5 (κ = 0.56) and substantial for categories 4 and 5 (κ = 0.67). The PPVs for subcategories 4a-4c were 23.74%, 70.67% and 81.25%, respectively. In addition, the total PPV for category 4 was 46.92% (183/390), and the total PPV for category 5 was 97.35% (184/189). Statistical results revealed that the PPVs of subcategories 4a and 4b differed significantly from the theoretical values (p < 0.05); the PPVs of subcategory 4c and category 5 were significantly correlated with the theoretical PPVs (p > 0.05). In conclusion, subcategories 4a and 4b have lower diagnostic efficiency than subcategory 4c and category 5. Inter-observer agreement for subcategories 4a-4c remains to be improved. The most common features of subcategories 4a-4c differ, but overlap. It is recommended that inexperienced doctors in primary hospitals not classify lesions into subcategories in clinical practice.

Comparison of Inter-Observer Variability and Diagnostic Performance of the Fifth Edition of BI-RADS for Breast Ultrasound of Static versus Video Images

Our aim was to compare the inter-observer variability and diagnostic performance of the Breast Imaging Reporting and Data System (BI-RADS) lexicon for breast ultrasound of static and video images. Ninety-nine breast masses visible on ultrasound examination from 95 women 19-81 y of age at five institutions were enrolled in this study. They were scheduled to undergo biopsy or surgery or had been stable for at least 2 y of ultrasound follow-up after benign biopsy results or typically benign findings. For each mass, representative long- and short-axis static ultrasound images were acquired; real-time long- and short-axis B-mode video images through the mass area were separately saved as cine clips. Each image was reviewed independently by five radiologists who were asked to classify ultrasound features according to the fifth edition of the BI-RADS lexicon. Inter-observer variability was assessed using kappa (κ) statistics. Diagnostic performance on static and video images was compared using the area under the receiver operating characteristic curve. No significant difference was found in κ values between static and video images for all descriptors, although κ values of video images were higher than those of static images for shape, orientation, margin and calcifications. After receiver operating characteristic curve analysis, the video images (0.83, range: 0.77-0.87) had higher areas under the curve than the static images (0.80, range: 0.75-0.83; p = 0.08). Inter-observer variability and diagnostic performance of video images was similar to that of static images on breast ultrasonography according to the new edition of BI-RADS.

Invasive ductal carcinoma of the breast with osteoclast-like giant cells and clear cell features: a case report of a novel finding and review of the literature

BACKGROUND

Osteoclast-like giant cells (OLGCs) are a rare histologic finding within a tumor of the breast. Although there has been discussion as to the pathogenesis and prognosis related to this finding, our understanding of its significance remains inconclusive. Clear cells are another unique histologic finding in breast tumors and are typically associated with tumors arising in other organs such as renal cell carcinoma.

CASE PRESENTATION

This is a case report of a 64-year-old female who presented with one tumor identified as invasive ductal carcinoma with a combination of OLGCs and clear cell features.

CONCLUSIONS

To our knowledge, this combination of findings has not been previously described in the literature and therefore represents another morphologic manifestation of breast carcinoma. As patients are diagnosed earlier and live longer, a growing number of these rare variants may be recognized and provide opportunities to further our understanding of the associated molecular pathways which could contribute to the possibility of therapeutic intervention.

Validation of the fifth edition BI-RADS ultrasound lexicon with comparison of fourth and fifth edition diagnostic performance using video clips

Purpose

The aim of this study was to evaluate the positive predictive value (PPV) and the diagnostic performance of the ultrasonographic descriptors in the fifth edition of BI-RADS, comparing with the fourth edition using video clips.

Methods

From September 2013 to July 2014, 80 breast masses in 74 women (mean age, 47.5±10.7 years) from five institutions of the Korean Society of Breast Imaging were included. Two radiologists individually reviewed the static and video images and analyzed the images according to the fourth and fifth edition of BI-RADS. The PPV of each descriptor was calculated and diagnostic performances between the fourth and fifth editions were compared.

Results

Of the 80 breast masses, 51 (63.8%) were benign and 29 (36.2%) were malignant. Suspicious ultrasonographic features such as irregular shape, non-parallel orientation, angular or spiculated margins, and combined posterior features showed higher PPV in both editions (all P<0.05). No significant differences were found in the diagnostic performances between the two editions (all P>0.05). The area under the receiver operating characteristics curve was higher in the fourth edition (0.708 to 0.690), without significance (P=0.416).

Conclusion

The fifth edition of the BI-RADS ultrasound lexicon showed comparable performance to the fourth edition and can be useful in the differential diagnosis of breast masses using ultrasonography.

Nonpalpable BI-RADS 4 breast lesions: sonographic findings and pathology correlation

PURPOSE

We aimed to evaluate ultrasonography (US) findings for Breast Imaging Reporting and Data System (BI-RADS) category 4 lesions using BI-RADS US lexicon and determine the positive and negative predictive values (PPV and NPV) of US with respect to biopsy results.

METHODS

Sonograms of 186 BI-RADS 4 nonpalpable breast lesions with a known diagnosis were reviewed retrospectively. The morphologic features of all lesions were described using BI-RADS lexicon and the lesions were subcategorized into 4A, 4B, and 4C on the basis of the physician's level of suspicion. Lesion descriptors and biopsy results were correlated. Pathologic results were compared with US features. PPVs of BI-RADS subcategories 4A, 4B, and 4C were calculated.

RESULTS

Of 186 lesions, 38.7% were malignant and 61.2% were benign. PPVs according to subcategories 4A, 4B, and 4C were 19.5%, 41.5%, and 74.3%, respectively. Microlobulated, indistinct, and angular margins, posterior acoustic features, and echo pattern were nonspecific signs for nonpalpable BI-RADS 4 lesions. Typical signs of malignancy were irregular shape (PPV, 66%), spiculated margin (PPV, 80%) and nonparallel orientation (PPV, 58.9%). Typical signs of benign lesions were oval shape (NPV, 77.1%), circumscribed margin (NPV, 67.5%), parallel orientation (NPV, 70%), and abrupt interface (NPV, 67.6%).

CONCLUSION

BI-RADS criteria are not sufficient for discriminating between malignant and benign lesions, and biopsy is required. Subcategories 4A, 4B, and 4C are useful in predicting the likelihood of malignancy. However, objective and clear subclassification rules are needed.

Variability in Observer Performance Between Faculty Members and Residents Using Breast Imaging Reporting and Data System (BI-RADS)-Ultrasound, Fifth Edition (2013)

Background

Ultrasonography (US) is a useful tool for breast imaging, yet is highly operator-dependent.

Objectives

We evaluated inter-observer variability and performance discrepancies between faculty members and radiology residents when describing breast lesions, by the fifth edition of breast imaging reporting and data system (BI-RADS)-US lexicon, and then attempted to identify whether inter-observer variability could be improved after one education session.

Patients and Methods

In total, 50 malignant lesions and 70 benign lesions were considered in our retrospective study. Two faculty members, two senior residents, and two junior residents separately assessed the US images. After the first assessment, the readers received one education session, and then reassessed the images in a random order. Inter-observer variability was measured using the kappa coefficient (κ). Performance discrepancy was evaluated by receiver operating characteristic (ROC) curves.

Results

For the faculty members, fair-to-good agreement was obtained in all descriptors and final assessment, while for residents, poor-to-moderate agreement was obtained. The areas under the ROC curves were 0.78 for the faculty members, 0.59 for the senior residents, and 0.52 for the junior residents, respectively. Diagnostic performance was significantly higher in the faculty members than the senior and junior residents (P = 0.0001 and < 0.0001, respectively). After one education session, the agreement in the final assessment was one level higher in the faculty members and senior residents, yet in the senior residents, the degree of agreement was still only fair. Moreover, in the junior residents, there was no improvement.

Conclusion

Investigative assessment of breast US by residents is inadvisable. We recommend continued professional resident training to improve the degree of agreement and performance.

Ultrasound Elastography Combined With BI-RADS-US Classification System: Is It Helpful for the Diagnostic Performance of Conventional Ultrasonography?

PURPOSE

To evaluate the additive diagnostic performance of ultrasound elastography (UE) to ultrasound (US) with the 2003 or 2013 Breast Imaging Reporting and Data System (BI-RADS)-US classification systems for the differentiation of benign and malignant breast lesions.

METHODS

From June 2010 to December 2012, 738 women with 770 breast lesions were recruited into this retrospective study. Breast lesions were evaluated separately by US, UE, and both. US assessment was based on the 2003 or 2013 BI-RADS-US, and UE assessment was based on a previously reported 5-point scale. Diagnostic performance of US, UE, and both was compared.

RESULTS

Before category 4 lesions were subdivided, the area under the receiver operating characteristic curve (AUC) for US, UE, and both were, respectively, 0.735, 0.877, 0.878 (P < .01). When subcategories of 4 lesions were considered, the AUC for US, UE, and both were, respectively, 0.865, 0.877, and 0.883 (P > .05). Adding UE to analysis of 4A lesions can decrease the percentages of malignancy to 2.56%.

CONCLUSION

When the 2003 BI-RADS was considered, UE could give US some help in differentiating breast lesions. However, when the 2013 BI-RADS was considered, UE gave little help to US, although it reduced unnecessary biopsies of benign category 4A lesions.

Combined Use of Ultrasound Elastography and B-Mode Sonography for Differentiation of Benign and Malignant Circumscribed Breast Masses

OBJECTIVES

To evaluate the diagnostic performance of combined B-mode sonography and ultrasound elastography for differentiation between benign and malignant breast masses with circumscribed margins.

METHODS

We analyzed 109 pathologically proven circumscribed breast masses. Two radiologists retrospectively reviewed B-mode sonograms and elastograms in consensus. Based on the American College of Radiology Breast Imaging Reporting and Data System, we determined categories of the masses on B-mode sonography. Elastographic scores were assessed by a 3-point scale (negative, 0; equivocal, 1; and positive, 2). When the elastographic score for a lesion was 0 or 2, we downgraded or upgraded the B-mode category, respectively; thus, the reclassified Breast Imaging Reporting and Data System category was defined as the "reclassification category." Mean category values for benign and malignant lesions were compared by a Student t test. The diagnostic performance of B-mode, elastographic, and reclassification assessments was compared by receiver operating characteristic curve analysis.

RESULTS

The mean B-mode category (2.5 versus 1.7), elastographic score (1.7 versus 0.8), and reclassification category (3.2 versus 1.6) were significantly higher in malignant than benign lesions (P < .001). The area under the curve for reclassification assessment was significantly higher than that for B-mode sonography (0.916 versus 0.795; P < .05). With a cutoff value between 1 and 2, the specificity was increased from 26.5% to 42.9% after reclassification.

CONCLUSIONS

For differentiation between benign and malignant circumscribed breast masses, combined use of B-mode sonography and elastography could provide a better diagnostic performance than B-mode sonography alone.

Breast Imaging-Reporting and Data System (BI-RADS) classification in 51 excised palpable pediatric breast masses

INTRODUCTION

The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) classification was developed to risk stratify breast lesions and guide surgical management based on imaging. Previous studies validating BI-RADS for US do not include pediatric patients. Most pediatric breast masses present as palpable lesions and frequently undergo ultrasound, which is often accompanied with a BI-RADS classification. Our study aimed to correlate BI-RADS with pathology findings to assess applicability of the classification system to pediatric patients.

METHODS

We performed a retrospective review of all patients who underwent excision of a breast mass at a single center from July 2010 to November 2013. We identified all patients who underwent preoperative ultrasound with BI-RADS classification. Demographic data, imaging results, and surgical pathology were analyzed and correlated.

RESULTS

A total of 119 palpable masses were excised from 105 pediatric patients during the study period. Of 119 masses, 81 had preoperative ultrasound, and BI-RADS categories were given to 51 masses. Of these 51, all patients were female and the average age was 15.9 years. BI-RADS 4 was given to 25 of 51 masses (49%), and 100% of these lesions had benign pathology, the most common being fibroadenoma.

CONCLUSIONS

Treatment algorithm based on BI-RADS classification may not be valid in pediatric patients. In this study, all patients with a BI-RADS 4 lesion had benign pathology. BI-RADS classification may overstate the risk of malignancy or need for biopsy in this population. Further validation of BI-RADS classification with large scale studies is needed in pediatric and adolescent patients.

Adding Ultrasound to the Evaluation of Patients with Pathologic Nipple Discharge to Diagnose Additional Breast Cancers: Preliminary Data

The aim of this study was to assess the malignancy yield of ultrasound Breast Imaging Reporting and Data System (BI-RADS) classification and the diagnostic value of adding ultrasound to diagnosis of breast cancer in patients with pathologic nipple discharge. Of 267 patients with pathologic nipple discharge seen from February 2003 to March 2011, 198 with histopathologic confirmation and follow-up data were included. Ultrasound images and mammograms were analyzed according to BI-RADS. The malignancy rate for each BI-RADS category and the difference in diagnostic performance resulting from the addition of ultrasound to mammography were calculated. Of the 198 enrolled patients, 34 were diagnosed with a malignancy. The malignancy rates obtained with the addition of ultrasound to mammography were 0.0% (0 of 27) for category 1, 5.9% (1/17) for category 2, 9.4% (5/53) for category 3, 21.5% (20/93) for category 4 and 100% (8/8) for category 5. The malignancy rates for mammography alone were 7.7%-9.0% for categories 1-3, 68.5% (13/19) for category 4 and 100.0% (5/5) for category 5. Adding US to mammography did not significantly increase sensitivity compared with mammography alone. Other diagnostic performance markers such as specificity and positive predictive value were not improved. Among patients for whom mammograms were available, ultrasound detected 5 breast cancers (26.3%) in addition to the 19 breast cancers found by positive mammography. Although it did not increase overall diagnostic performance in patients with pathologic nipple discharge, addition of ultrasound to mammography did detect an additional 26.3% of malignant lesions.

Synchronous BI-RADS Category 3 Lesions on Preoperative Ultrasonography in Patients with Breast Cancer: Is Short-Term Follow-Up Appropriate?

Purpose

Breast ultrasonography (US) has been widely used in the preoperative examination of patients with breast cancer. Breast Imaging Reporting and Data System (BI-RADS) category 3 (C3) lesions (probably benign) are regarded as having a low probability of malignancy (≤2%). The purposes of this study were to verify the malignancy rates for synchronous BI-RADS C3 lesions in patients with breast cancer and consider appropriate management strategies for these lesions.

Methods

Between January 2010 and January 2013, a total of 161 patients underwent surgery in our institute for breast cancer and synchronous BI-RADS C3 lesions. In the US reports, we found records of 219 synchronous BI-RADS C3 nodules in 161 patients. They were excised during surgery for breast cancer management. Stepwise logistic regression analysis was used to identify predictors of malignancy for synchronous BI-RADS C3 lesions.

Results

The rate of malignancy among the 219 BI-RADS C3 lesions was 9.6%. In simple logistic regression analysis, the size of the primary tumor (p<0.001), pathologic T (pT) stage (p=0.002), and progesterone receptor (PR) status of the primary tumor (p=0.029) were significant predictive factors. In multiple logistic regression analysis, the pT stage and PR status of the primary tumor remained significant predictors (p=0.004 and p=0.003, respectively), and human epidermal growth factor receptor 2 (HER2) was identified as another significant factor (p=0.006).

Conclusion

In patients with breast cancer who are scheduled for surgery, needle biopsy or excision should be considered for synchronous BI-RADS C3 lesions identified on preoperative US when the primary tumor has the following risk factors: large size, high PR expression, and HER2 positivity.

Undiagnosed Breast Cancer: Features at Supplemental Screening US

PURPOSE

To retrospectively investigate the reasons for and features of undiagnosed cancers at previous supplemental screening ultrasonography (US) in women who subsequently received a diagnosis of breast cancer.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the requirement to obtain informed patient consent. The study consisted of 230 women (median age, 49 years; age range, 29-81 years) with 230 pairs of US examinations (prior and subsequent examinations) performed between December 2003 and August 2013 who were found to have cancer (median interval, 12 months; range, 2-24 months). The authors compared the clinical-pathologic features of patients with negative findings on prior images with those of patients with visible findings on prior images. Findings visible at prior US were classified as actionable or underthreshold by means of a blinded review by five radiologists. Lesions classified as Breast Imaging Reporting and Data System category 4 or 5 by fewer than three readers were determined to be underthreshold. Reasons for undiagnosed cancers and their imaging features were analyzed.

RESULTS

Among the 230 prior US examinations, 72 (31.3%) showed visible findings and 158 (68.7%) showed negative findings. High-nuclear-grade cancers and triple-negative cancers were more common in patients with negative findings than in those with visible findings (P = .023 and P = .006, respectively). Blinded review revealed that 57 of the 72 visible findings (79%) were actionable. Misinterpretation (39% [28 of 72 lesions]) and multiple distracting lesions (17% [12 of 72 lesions]) were the two most common reasons for missing these actionable findings, which showed more noncircumscribed margins than did underthreshold findings (P = .028).

CONCLUSION

At supplemental screening breast US, close attention should be paid to the presence of a margin that is not circumscribed, and multiple lesions should be separately assessed to reduce the number of missed breast cancers.

A set of shear wave elastography quantitative parameters combined with ultrasound BI-RADS to assess benign and malignant breast lesions

The goal of this study was to determine whether a combination of shear wave elastography (SWE) quantitative parameters could improve the accuracy of ultrasonography in the differentiation of benign and malignant breast lesions. Two hundred seventy-nine breast lesions in 251 women were evaluated with ultrasonography and SWE; pathologic results of all lesions were available. Each lesion was classified according to the Breast Imaging Reporting and Data System (BI-RADS) for ultrasound. SWE quantitative parameters, including maximum elastic value (Emax), mean elastic value (E mean), standard deviation (SD) and ratio of E mean of the lesion to E mean of the surrounding parenchyma (E ratio), were recorded. A receiver operating characteristic curve was used to determine their cutoff values. When any of the four parameters was equal to or higher than the cutoff value, the set of SWE parameters was counted as positive. When both BI-RADS and the set were positive, lesions were evaluated as positive for malignancy. We compared the performance of this combination with use of BI-RADS, Emax, E mean, SD or E ratio alone and also with the combination of BI-RADS and Emax for benign/malignant differentiation. The combination of Emax, E mean, SD, or E ratio with BI-RADS had a sensitivity, specificity, positive predictive value, negative predictive value, accuracy and Youden index of 0.967, 0.912, 0.908, 0.969, 0.938 and 0.879, respectively. The accuracy was the highest (p < 0.01) without loss of sensitivity. Combining a set of SWE quantitative parameters (E max, E mean, SD and E ratio) could improve the accuracy of ultrasonography in differentiation of benign from malignant breast lesions, without loss of sensitivity.

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.

Prognostic importance of ultrasound BI-RADS classification in breast cancer patients

OBJECTIVE

We investigated the prognostic importance of pre-operative Breast Imaging Reporting and Data System classification in ultrasound imaging.

METHODS

Histopathological differences and disease-free survival were analyzed in Breast Imaging Reporting and Data System classification subgroups. Univariate and multivariate analyses were used to identify the prognostic factors.

RESULTS

We identified 531 invasive breast cancer patients eligible for this study. Most patients classified as Breast Imaging Reporting and Data System 5 had large tumors and a higher rate of lymph node metastasis. However, hormonal receptor or HER-2 status did not differ according to Breast Imaging Reporting and Data System classification. During a median post-operative follow-up of 42.0 months, 43 patients were diagnosed with a disease-specific event. Disease-free survival was significantly lower in patients with Breast Imaging Reporting and Data System 5 than in patients with Breast Imaging Reporting and Data System 3-4. Subgroup analysis of patients with invasive breast cancer of Stage I showed that Breast Imaging Reporting and Data System 5 was an independent negative prognostic indicator of disease-free survival (hazard ratio 9.195; 95% confidence interval, 1.175-71.955; P = 0.035).

CONCLUSIONS

Breast Imaging Reporting and Data System classification might be considered as prognostic factors especially in Stage I breast cancer. Further confirmatory studies are needed.

Mammographic and sonographic features of triple-negative invasive carcinoma of no special type

The aim of this study was to compare the mammography, ultrasound (US) and histologic features of triple-negative (TN) invasive carcinoma of no special type (NST) to non-TN invasive carcinoma of NST. The second aim was to assess whether the distinct imaging characteristics of TN breast cancer would persist after controlling for the histologic features. A total of 344 invasive carcinomas of NST in 337 patients from January 2007 to February 2008 were included in this study. Two radiologists retrospectively reviewed the mammography and US findings using the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) lexicon and our institution's criteria. On mammography, TN invasive carcinoma of NST most commonly presented as a mass with round shape and non-spiculated margin. On US, it was more likely to have internal hypoechogenicity, an abrupt boundary and posterior acoustic enhancement. TNBC lacked major suspicious imaging findings such as an irregular shape, spiculated margin and calcification.