Fig. 8.

40-year-old woman with palpable mass in her left breast.

A. On sonography (left: transverse view, right: longitudinal view), oval microlobulated hypoechoic mass with echogenic halo and nonparallel orientation is seen and classified as BI-RADS category 4b. Result of sonography-guided 14-gauge core needle biopsy indicates fibroadenoma, which is considered as discordant benign. B. Surgically excised specimen reveals well circumscribed, lobulated mass with tumoral florid adenosis, consistent with adenosis tumor (Hematoxylin & Eosin staining; original magnification, × 100).