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

Abstract

ORIGINAL ARTICLE 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. METHODSSonograms 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. RESULTSOf 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.A dvancements in ultrasonography (US) equipment has significantly increased the value of US in breast imaging (1). Especially in women under the age of 50, detection of mammographically occult masses by US has increased up to 27% (1, 2). With the increasing use of US in routine breast imaging, in 2003 the American College of Radiology developed the first version of Breast Imaging Reporting and Data System (BI-RADS) US lexicon in order to standardize breast lesion characterization with US, as with mammography (3). In 2013, the second version of BI-RADS US lexicon was published in the fifth edition of BI-RADS atlas (4). The first version of BI-RADS US lexicon included shape, orientation, margins, lesion boundary, echo pattern, posterior acoustic features, and surrounding tissue alterations as descriptors (1-3, 5-8). The changes were minimal in the second version of BI-RADS US lexicon, with no changes in shape, orientation, margin, and feature descriptors; however, lesion boundary was removed. There were some differences in the nomenclature such as "posterior features" instead of "posterior acoustic features," and "associated features" instead of "surrounding tissue alterations." In the second version, "elasticity assessment" was added among the associated features and heterogeneous term was added to its echo pattern. Macrocalcification was removed from calcifications terminology, but intraductal was added (4)...

Real‐time elastosonography of lipomatous vs. malignant subcutaneous neoplasms in dogs: Preliminary results

“…Statistical analyses did not identify any significant relationships between the shape, regularity of the margins, and the final diagnosis. It could be hypothesized that the more irregularly defined a lesion is, then the more likely it is to be locally infiltrative and thus malignant, in accordance with what has been previously reported in human patients; however, this was not identified in our population . Moreover the heterogeneity and variable echotexture of the neoplasms were not statistically related to the final diagnosis, supporting the fact that B‐mode ultrasound alone is less sensitive in detecting malignant subcutaneous nodules, as previously reported in the literature …”

“…3 Imaging using B-mode ultrasonography only provides information about the shape, margins, and echogenicity of lesions, and may display similar features between neoplastic and benign soft tissue lesions, as reported in humans. 6,7 In this context, elastosonography has been introduced into both human and veterinary medicine as a tool for classifying the nature of mammary lesions, suggesting malignancy if decreased plasticity is detected. [8][9][10][11][12][13] Elastosonography provides information on tissue elasticity, assigning different elastic strains to different chromatic patterns.…”

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

“…Elverici et al (2015) assessed the classification of 265 lesions in 240 female patients, according to the second edition and calculated PPVs of 19.5%, 41.5% and 74.3% respectively for subcategories 4a, 4b and 4c; however, the PPV for subcategory 4a was still higher than the theoretical value in their study. The problem has not been completely solved.…”

“…All statistical data were calculated with the SPSS 13.0 (SPSS, Chicago, IL, USA). As recommended by earlier studies (Elverici et al 2015;Heinig et al 2008;Lazarus et al 2006), we estimated the positive predictive values (PPVs) for subcategories 4a-4c and category 5 and then make compared them with the expected malignancy ratios (theoretical values). The c 2 test (for PPVs of category 4a-4c lesions) and the binomial test (for PPVs of category 5 lesions) were used to determine the significance of differences.…”

“…Under this condition, lesions with most suspicious features will easily be classified into category 5; however, other suspicious lesions with fewer features will cause a lack of diagnostic confidence and be very difficult to classify into subcategories. From the data on the distribution of features for lesions (Table 5) we analyzed, although new features are delineated in the second edition of the BI-RADS US lexicon, a clear and objective evaluation system is still lacking (Elverici et al 2015). The final results are based on the judgment of doctors.…”