Sonographic Appearance of Lesions Diagnosed as Lobular Neoplasia at Sonographically Guided Biopsies

OBJECTIVE. The objective of our study was to review the sonographic features of breast lesions yielding lobular neoplasia (LN) at sonographically guided biopsy, evaluate the surgical pathology outcome of these lesions, and determine if imaging findings or clinical features can be used to predict an upgrade to malignancy. MATERIALS AND METHODS. Of the 8205 sonographically guided breast biopsies (14-gauge cores) performed from 2007 through 2014, 22 yielded a diagnosis of LN, which means that LN was the most severe pathologic lesion. Imaging features were analyzed in consensus by two radiologists. Correlation of biopsy findings with definitive pathologic results was performed when available. RESULTS. Twenty-two LN lesions (20 patients [mean age +/- SD, 52.05 +/- 13.66 years]) were diagnosed at biopsy. Of the LN lesions that were seen on mammography (6/22, 27.3%), most lesions appeared as masses (3/6, 50%). On sonography, LN lesions (mean size, 8.10 mm) appeared as masses (15/22, 68.2%) with oval shape (10/15, 66.7%), well-circumscribed or microlobulated margins (11/15, 73.3%), hypoechoic echotexture (10/15, 66.7%), posterior enhancement (73.3%, 11/15), and parallel orientation (8/15, 53.3%). Most of the masses were categorized as BI-RADS category 4 (21/22, 95.5%). Seven lesions (7/22, 31.8%) appeared as areas of shadowing or distortion without discrete masses. Twenty (20/22, 90.9%) lesions were excised surgically, and pathology results led to an upgrade in five lesions (5/20, 25% [one nonmass lesion and four masses]). Neither mammographic nor sonographic features were associated with malignant outcome (p > 0.05). CONCLUSION. LN diagnosed at sonographically guided 14-gauge core needle biopsy does not show any specific features according to the BI-RADS lexicon and is associated with a 25% underestimation rate. No clinical or imaging characteristic is predictive of malignancy.