Sonographic findings in focal fibrocystic changes of the breast

The purpose of this study was to identify the spectrum of sonographic appearances in histologically proven focal fibrocystic changes (FC) of the breast to enhance understanding of imaging findings in this commonly encountered benign condition of the breast. During a 28-month period, the pathology database at two breast centers was searched to identify all patients with a pathologic diagnosis of focal FC resulting from biopsy of a focal mammographic, sonographic, or palpable abnormality and who had undergone sonographic evaluation before biopsy. The authors included lesions with a pathologic diagnosis of FC with or without a specific histologic subtype, such as stromal fibrosis, sclerosing adenosis, and apocrine metaplasia. In 58 patients, there were 60 lesions with a pathologic diagnosis of focal FC. Sonographically, focal FC appeared as solid mass in 28 cases (46.6%) and as cysts in eight (13.3%). In nine cases (15%), heterogeneously echogenic tissue was seen, and in the remaining 15 (25%) cases, there was no sonographically visible focal change. Thirteen of the 28 (46.4%) masses were classified as sonographically indeterminate. One mass was classified as probably malignant, and 14 masses were sonographically benign. A significant number of focal FC appear as solid masses. The sonographic features are not specific enough to differentiate between those that have a dominant component of focal fibrosis, sclerosing adenosis, or apocrine metaplasia from FC without a specific histologic subtype. Many of these solid masses may appear indeterminate, based on published criteria. An understanding of the imaging findings also helps to avoid repeat biopsy for discordant histologic and imaging findings.