Objectives: To evaluate the ultrasound (US) features and rate of upgrade to malignancy in atypical apocrine lesions (AALs) of the breast, diagnosed on percutaneous needle biopsy.
Methods: This retrospective study included 17 AALs diagnosed by needle biopsy in 15 patients. For 16 of the 17 AALs, subsequent surgical excision (n = 14) or 8-gauge vacuum-assisted biopsy (n = 2) was performed. Ultrasound features were retrospectively analyzed according to the American College of Radiology Breast Imaging Reporting and Data System lexicon.
Results: Of 17 AALs, 13 (76.5%) were atypical apocrine hyperplasia; 3 (17.6%) were atypical apocrine adenosis; and 1 (5.9%) was combined atypical apocrine hyperplasia and atypical apocrine adenosis on needle biopsy. Subsequently, 4 of 16 AALs (25%) were upgraded to malignancy at surgical excision. On US imaging, all 17 lesions presented as masses, which were mainly irregular and noncircumscribed (n = 8) or oval/round and noncircumscribed (n = 7) with isoechogenicity or hypoechogenicity. Rarely, an AAL would show complex cystic and solid echogenicity (n = 1) or appear as a hypoechoic mass with oval shape and a circumscribed margin (n = 1).
Conclusions: Atypical apocrine lesions of the breast often showed suspicious malignant features on US imaging. Given the high upgrade rate (25%), the diagnosis of an AAL by needle biopsy warrants subsequent surgical excision.
Keywords: atypical apocrine lesion; breast; ultrasound; upgrade rate.
© 2020 by the American Institute of Ultrasound in Medicine.