Breast MRI Does Not Help Differentiating Radial Scar With and Without Associated Atypia or Malignancy.

PURPOSE: To review breast magnetic resonance imaging (MRI) features of radial scar (RS) with and without associated atypia/malignancy. METHODS: Twenty-eight (mean age 56.8) patients diagnosed with 30 biopsy-proven RS (n = 25, ultrasound-guided 14-gauge, n = 5, stereotactically guided 9-gauge) subsequently underwent breast MRI followed by surgery. Magnetic resonance imaging protocol included axial T1, axial fat sat T2, and postgadolinium in axial and sagittal planes. Two radiologists reviewed the mammographic and MRI findings in consensus according to the Breast Imaging Reporting and Data System lexicon. RESULTS: Of the 30 RSs excised surgically, 14 (14/30, 47.7%) were not associated with atypia/malignancy while atypia/malignancy was found in 16 (16/30, 53.3%) RSs. Three (3/30, 10%) RS lesions did not enhance on dynamic MR. Mean lesion size on MRI was 1.4 cm (range, 0.5-5 cm). Seventeen (17/30, 56.7%) lesions presented as nonmass enhancement and 9 (9/30, 30%) as masses. Nonmass lesions showed focal distribution (13/17, 76.5%) and heterogeneous enhancement (15/17, 88.2%). Masses showed irregular shape and margins (6/9, 67%) and heterogeneous enhancement (8/9, 89%). Multivariate analysis did not show any significant difference in MRI presentation between RS only and RS associated with atypia/malignancy. CONCLUSION: Breast MRI does not help differentiate between RS with or without associated atypia/malignancy.

Value of Shear Wave Elastography for the Differentiation of Benign and Malignant Microcalcifications of the Breast.

OBJECTIVE. The objective of our study was to evaluate whether shear wave elastography (SWE) can differentiate benign from malignant microcalcifications of the breast when detected on ultrasound (US). SUBJECTS AND METHODS. Between February 9, and June 23, 2016, 74 patients with mammographically detected suspicious microcalcifications underwent breast US. When microcalcifications were identified on US, stiffness was assessed using SWE. Biopsy was subsequently performed under US guidance using a 10-gauge vacuum-assisted needle. Qualitative and quantitative elastography results were compared between benign and malignant calcifications as well as between pure ductal carcinoma in situ and lesions with invasive components using the Mann-Whitney U test. ROC curves were created to assess the performance of SWE in detecting malignancy and invasive components. RESULTS. Twenty-nine groups of microcalcifications in 29 patients were identified on US. At pathology, 16 groups were benign and 13 were malignant. Stiffness of malignant calcifications was significantly higher than that of the benign ones (p = 0.0004). The AUC, sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of SWE for the diagnosis of malignancy were 0.89, 69%, 100%, 80%, 100%, and 86%, respectively, and for detection of an invasive component were 0.93, 75%, 100%, 75%, 100%, and 85%. CONCLUSION. SWE has the potential to differentiate benign from malignant micro-calcifications of the breast when detected on US with high specificity.

Can strain elastography improve the characterization of breast lesions identified during second-look MRI-directed sonographic examination?

PURPOSE: To evaluate strain elastography as a complementary tool for characterization of lesions identified during second-look MRI-directed sonographic examination. METHODS: We reviewed 83 breast lesions evaluated with MRI, secondlook ultrasound (US) and strain elastography in 75 consecutive patients (median age, 56 years). US-guided biopsies were performed in all cases. RESULTS: After histopathological examination, 44 lesions were benign, 38 were malignant and 1 was high-risk. At MRI, the mean size of the lesions was 12 mm. Forty lesions (48.2%) appeared as masses, 30 (36.1%) as "non-masses" and 13 (15.7%) as "foci." At second-look US examination, 56 (67.5%) appeared as masses (mean size, 7 mm) and 27 (32.5%) as non-masses (mean size, 14 mm). At strain elastography, among the 39 malignant/high risk lesions, 5 (12.8%) had a score of 4 or 5, whereas 16 (41%) had a score of 1 and 2 (false negative). Among the 44 benign lesions, 36 (82%) had a score of 1 or 2, whereas none had a score of 5. Sensitivity and specificity of strain elastography in the diagnosis of breast cancer were 58% and 81%, respectively. CONCLUSION: The addition of strain elastography offers no benefit in the characterization of lesions identified on second-look US after breast MRI.(E1, 3).

Evaluating the Impact of Breast Density on Preoperative MRI in Invasive Lobular Carcinoma.

BACKGROUND: The focus of this study was to assess the accuracy of breast MRI in predicting pathologic tumor size in invasive lobular carcinoma (ILC) and to evaluate the incidence and factors associated with the detection of additional MRI lesions in ILC patients. STUDY DESIGN: We retrospectively reviewed data from patients with stage I to III ILC diagnosed between 2010 and 2016 at our institution. Univariable and multivariable logistic regression were used to determine factors associated with detection of additional suspicious lesions on MRI. RESULTS: The cohort included 99 women with ILC who underwent preoperative MRI, with a median age of 61 years (range 35 to 80 years). The sensitivity of MRI for detecting invasive lobular carcinoma was 99%, higher than that of mammography (68%) and ultrasound (92%). Mammography and ultrasound had a tendency to underestimate ILC, and MRI estimates of final tumor size were concordant in the majority (58.6%) of cases, with a median discordance of -2 mm. Magnetic resonance imaging detected additional ipsilateral malignancy in 23.2%, occult contralateral disease in 3.0%, and altered surgical management in 29.3% of ILC cases. In multivariable analyses, factors significantly associated with additional suspicious findings on MRI included higher breast density (odds ratio 3.19; 95% CI 1.01 to 10.0) and lymph node-positive disease (odds ratio 4.02; 95% CI 0.96 to 16.9). CONCLUSIONS: Preoperative MRI is a useful adjunct to conventional breast imaging in ILC, particularly in women with dense breast tissue.

The Positive Outcome of MRI-Guided Vacuum Assisted Core Needle Breast Biopsies Is Not Influenced by a Prior Negative Targeted Second-Look Ultrasound.

PURPOSE: The study sought to investigate the outcome of breast magnetic resonance-guided biopsies as a function of the indication for magnetic resonance imaging (MRI), the MRI features of the lesions, and the performance or not of a targeted second-look ultrasound (SLUS) prior breast MRI-guided biopsy. METHODS: We identified 158 women with MRI-detected breast lesions scheduled for MRI-guided biopsy (2007-2013). Patient demographics, performance of targeted SLUS, imaging characteristics, and subsequent pathology results were reviewed. RESULTS: Three biopsies were deferred, and 155 lesions were biopsied under MRI guidance (155 women; median age 55.14 years; range 27-80 years). Ninety-eight women underwent a SLUS prior to the MRI-guided biopsy (63%). Of the 155 biopsied lesions, 23 (15%) were malignant, 106 (68%) were benign, and 26 (17%) were high risk. Four of 15 surgically excised high-risk lesions were upgraded to malignancy (27%). Most of the biopsied lesions corresponded to non-mass-like enhancement (81%, 126 of 155) and most of the biopsies (52%, 81 of 155) were performed in a screening context. No demographic or MRI features were associated with malignancy. No differences were noted between the 2 subgroups (prior SLUS vs no prior SLUS) except for the presence of a synchronous carcinoma associated with a likelihood of targeted SLUS before MRI-guided biopsy (P = .001). CONCLUSION: A negative SLUS does not influence the pathology outcome of a suspicious lesion biopsied under MR guidance.

Imaging features and conspicuity of invasive lobular carcinomas on digital breast tomosynthesis.

OBJECTIVE: To review the imaging features of invasive lobular carcinoma (ILC) seen on digital breast tomosynthesis (DBT) in comparison with invasive ductal carcinoma (IDC), and to evaluate whether DBT could improve conspicuity and tumour size assessment of ILC in comparison with digital mammography (DM). METHODS: Institutional review board with waiver of informed consent was obtained for this retrospective study. Patients with ILC or IDC who underwent DBT and DM at the time of diagnosis were included. DM and DBT images were reviewed in consensus by two breast radiologists in order to assess imaging features, conspicuity and maximum tumour diameter of ILC and IDC. Pathology on the surgical specimen was considered the standard of reference for assessment of tumour size. RESULTS: 43 patients (20 patients with ILC and 23 patients with IDC) were included. On DBT, compared with IDC, ILC presented less frequently as masses (40% vs 78%) (p = 0.01) and more frequently as isolated distortion (20% vs 0%) (p = 0.03). ILC presented more often as asymmetries (60%) than masses (20%) on DM (p = 0.02) but not on DBT (35% vs 40%; p = 1.00). Conspicuity of ILC was significantly higher on DBT than on DM (p = 0.002), while the difference between the two techniques was not significant for IDC (p = 0.2). Regarding ILC, concordance in tumour size measurement between DBT and pathology was fair (intraclass correlation coefficient = 0.24). CONCLUSION: ILC rarely presented as dense masses but frequently demonstrated architectural distortion on DBT. DBT increased lesion conspicuity but failed to accurately assess tumour size of ILC. Advances in knowledge: (1) This study describes specific features of ILC on DBT. (2) It shows that DBT can improve conspicuity of ILC.

Differentiation of Fibroadenomas and Pure Mucinous Carcinomas on Dynamic Contrast-Enhanced MRI of the Breast Using Volume Segmentation for Kinetic Analysis: A Feasibility Study.

OBJECTIVE: The objective of this study was to retrospectively evaluate the diagnostic performance of volume-based kinetic analysis in dynamic contrast-enhanced MRI (DCE-MRI) of the breast for the differentiation of fibroadenomas (FAs) with high T2 signal intensity from pure mucinous carcinomas (PMCs). MATERIALS AND METHODS: A review of records from 2007 to 2013 that were stored in the pathology department database at our institution identified nine patients with PMCs (defined as tumor cells with a mucinous component ≥ 90%) who underwent preoperative breast MRI. The PMCs were compared with 15 biopsy-proven FAs from 13 patients. Characteristics noted on DCE-MRI were evaluated using computer-assisted diagnosis software. For each mass, the proportion of progressive enhancement in the lesion at the delayed phase was quantified. Both groups of masses were compared using a Wilcoxon signed rank test. A ROC curve was used to define an appropriate cutoff point. RESULTS: The median rate of progressive enhancement was 100% (range, 99-100%) for FAs and 97% (range, 87-99%) for PMCs (p = 0.0326). The AUC of the kinetic curve for progressive enhancement was 0.7519 (95% CI, 0.5258-0.9407). A more appropriate cutoff value to maximize sensitivity and specificity was 98.5%. With this cutoff, sensitivity was 66.7% (95% CI, 11.1-100%) and specificity was 80% (95% CI, 39.6-99.8%) for the diagnosis of PMCs. CONCLUSION: Volume-based kinetic analysis may aid in differentiating FAs from PMCs on DCE-MRI studies of the breast.

Value of pre-operative breast MRI for the size assessment of ductal carcinoma in situ.

OBJECTIVE: To retrospectively evaluate the accuracy of pre-operative breast MRI and mammography in determining the size of ductal carcinoma in situ (DCIS) compared with the histopathological results. METHODS: 79 patients [mean age: 56.5 (standard deviation 10.2) years] with pathologically proven DCIS (79 lesions) obtained a bilateral mammogram and a pre-operative contrast-enhanced MRI. The accuracy of MRI and mammography to detect tumour size were estimated and compared, using histopathological size as the gold standard, on the subjects with measurements with both modalities (n = 60). RESULTS: MRI detected 67 (85%) lesions, mammography detected 72 (91%) and both modalities detected 60 (76%). Median DCIS size detected by mammography vs MRI was smaller (1.55 vs 1.65 cm). Out of these 60 cases, compared with the histopathological size, the accuracy of MRI and mammography was 0.66 and 0.56, respectively (p = 0.045). MRI showed better accuracy than mammography for younger patients (age ≤ 50 years, p = 0.003). For tumour nuclear grade, there was a statistically significant difference for the intermediate level, with higher accuracy for MRI (p = 0.03). CONCLUSION: MRI was more accurate than mammography in DCIS size assessment when visible, particularly in lesions of intermediate grade and in patients less than 50 years of age. ADVANCES IN KNOWLEDGE: Breast MRI may help in management of DCIS of intermediate grade and in females less than 50 years of age.

Retroareolar Carcinomas in Breast Ultrasound: Pearls and Pitfalls.

Breast Ultrasound (US) is an important tool for both screening and diagnostic examinations. Although breast US has benefitted from significant recent technical improvements, its use for the retroareolar region is known to be more challenging than for other locations. The retroareolar location was defined by Giess et al. in 1998 as the region where any lesion is situated at less than two cm from the nipple and/or involves the nipple-areolar complex on mammogram. Understanding of the complex anatomy and physiology of the nipple-areolar region is important to avoid misinterpretation and misdiagnosis. The ability for the breast imager to manage difficulties related to the retroareolar area is paramount by adjusting settings (compounding, frequency, Doppler) and utilizing specific manoeuvers. Cases illustrating difficulties encountered in diagnosis of retroareolar carcinomas are presented.

Atypical ductal hyperplasia diagnosed at sonographically guided core needle biopsy: frequency, final surgical outcome, and factors associated with underestimation.

OBJECTIVE: The purposes of this article were to review the mammographic and sonographic features of breast masses yielding atypical ductal hyperplasia (ADH) at sonographically guided biopsy, evaluate the surgical pathology outcome of these lesions, and determine whether clinical or imaging features can be used to predict upgrade to malignancy. MATERIALS AND METHODS: Among 6325 sonographically guided biopsies (2003- 2010) (14-gauge cores), 56 yielded the diagnosis of ADH (0.9%). Six patients were excluded (lost to follow-up). Fifty lesions were surgically excised in 45 patients. Mammographic and sonographic features were analyzed in consensus by two radiologists using the BI-RADS lexicon. RESULTS: Forty-five patients (mean age, 56 years; 12 < 50 years; six with synchronous breast carcinoma) had 50 ADH lesions (median size, 0.6 cm). Surgical excision yielded malignancy in 28 cases (56% underestimation rate). Among 42 mammograms (47 lesions), 30 lesions were identified (30/47, 64%) as masses (12/30, 40%), asymmetric densities (10/30, 33%), microcalcifications (4/30, 13%), and architectural distortions (4/30, 13%). Sonographically, most lesions appeared as hypoechoic masses (64%, 30/47) with irregular shape (51%, 24/47), microlobulated margins (49%, 23/47), no posterior acoustic feature (25/47, 53%), abrupt interface (70%, 33/47), and parallel orientation (57%, 27/47). No mammographic and sonographic features were associated with malignant outcome, whereas age less than 50 years (p = 0.03) and synchronous malignancy (p = 0.03) were associated with malignant outcome. CONCLUSION: ADH diagnosed at sonographically guided 14-gauge core needle biopsy shows a high underestimation rate. Synchronous carcinoma or age less than 50 years is associated with malignant outcome.

Flat epithelial atypia of the breast: pathological-radiological correlation.

OBJECTIVE: This study was undertaken to determine the prevalence of flat epithelial atypia at ultrasound-guided and stereotactically guided needle biopsies, to describe the mammographic and sonographic features of flat epithelial atypia, and to determine the significance of lesions diagnosed as flat epithelial atypia at imaging-guided needle biopsies. MATERIALS AND METHODS: Retrospective review of a database of 1369 consecutive sonographically and stereotactically guided needle biopsies performed during a 12-month period yielded 33 lesions with flat epithelial atypia as the most severe pathologic entity (32 patients). Two radiologists retrospectively reviewed the imaging presentation, by combined consensus, according to the BI-RADS lexicon. RESULTS: Twenty-two of 33 flat epithelial atypia diagnoses (67%) were obtained under stereotactic guidance, and 11 (33%) were obtained under sonographic guidance. Six patients had synchronous breast cancer. Flat epithelial atypia lesions presented mammographically most often as microcalcifications (20/33 [61%]) distributed in a cluster (14/20 [70%]) with amorphous morphology (13/20 [65%]). Sonographically, flat epithelial atypia lesions appeared most often as masses (9/11 [82%]), with an irregular shape (6/9 [67%]), microlobulated margins (5/9 [56%]), and hypoechoic or complex echotexture (7/9 [78%]). Twenty-eight of 33 lesions (85%) were surgically excised, confirming the flat epithelial atypia diagnosis in 11 of the 28 lesions (39%), yielding carcinoma in four (14%) and atypical ductal hyperplasia in six (21%). Columnar cell changes without atypia were diagnosed in four lesions (14%), and lobular carcinoma in situ was diagnosed in three lesions (11%). CONCLUSION: Mammographic and sonographic presentation of flat epithelial atypia is not specific (clustered amorphous microcalcifications and irregular, hypoechoic or complex masses). Given the underestimation rate of malignancy, surgical excision should be considered when imaging-guided biopsy yields flat epithelial atypia.

Cavernous hemangioma of the breast: mammographic and sonographic findings and follow-up in a patient receiving hormone-replacement therapy.

We report the case of a 78-year-old woman who had been receiving hormone-replacement therapy (HRT) for 6 years and had a 4-month history of a painless nodule in the 9 o'clock position in her right breast. Mammography performed 4 years previously had shown a 4-mm bilobed, ovoid, well-defined nodule in that location; mammography performed 1 year previously had shown that the nodule had increased to 6 mm. We performed mammographic and sonographic examinations, which revealed a 10-mm ovoid nodule in the same 9 o'clock position in the right breast. The imaging findings appeared to indicate benignity, but because of the increasing size of the nodule, we undertook an ultrasound-guided large-core needle biopsy. The histopathologic diagnosis was typical cavernous hemangioma. It was not excised, but HRT was discontinued. Follow-up mammography and sonography 8 months later showed that the nodule had decreased to 6 mm. We believe that the HRT played a contributory role in the increasing size of this patient's cavernous hemangioma. The use of ultrasound-guided large-core needle biopsy is reliable enough to ascertain the benignity of such masses and can thus avoid, if it is clinically appropriate, the need for their surgical removal.