Secretory Carcinoma of the Breast

Objective. The purpose of this series was to evaluate the sonographic features of secretory carcinoma of the breast. Methods. Between 1994 and 2006, 9 patients had histologically confirmed secretory carcinoma of the breast in our institution, and 6 of them underwent breast sonography. We retrospectively evaluated the sonographic findings of the patients in correlation with other available images and reviewed the clinical records. Results. Clinical manifestations were a palpable mass (n = 3), a bloody nipple discharge (n = 1), and screening‐detected abnormalities (n = 2). Breast sonograms showed masses with a round or oval (n = 5) or tubular (n = 1) shape, with relatively well‐circumscribed (n = 2) or partially microlobulated (n = 4) margins, and with a hypoechoic (n = 4) or an isoechoic (n = 2) internal echo texture. Most lesions were single nodules (n = 3) or groups of nodules (n = 2) measuring 1 cm or smaller, except 1 mass measuring 3.5 cm with axillary lymph node metastasis. Two cases had associated ductectasia. Sonographic assessments were classified as Breast Imaging Reporting and Data System category 3 in 2 cases, category 4A in 3 cases, and category 4B in 1 case. Conclusions . Secretory carcinoma of the breast is frequently shown as a small benign‐looking nodule or group of nodules or sometimes as an intraductal lesion with a low clinical stage on sonography. Although secretory carcinoma is a rare breast malignancy, awareness of its sonographic features will be helpful for the differential diagnosis.