Imaging Manifestation of Adenoid Cystic Carcinoma of the Breast

摘要

Adenoid cystic carcinoma (ACC) is most commonly observed as a tumor of the salivary glands, but it also arises in breast tissue. Adenoid cystic carcinoma of the breast is a particularly uncommon subtype of breast cancer and constitutes roughly 0.1% of all breast malignancies. Although it parallels ACC of the salivary glands with respect to microscopic characteristics, immunologic phenotypes and even the molecular genetic defect, the biological behavior of these 2 entities is different. Adenoid cystic carcinoma of the breast carries a more favorable prognosis than that of the salivary glands. Adenoid cystic carcinoma of the breast is frequently negative for estrogen receptor (ER) and progesterone receptor (PR) proteins, and Her-2 gene amplification (triple-negative). Interestingly, unlike the poor prognosis that is associated with other triple-negative breast cancers, ACC has been reported to have excellent outcomes. The incidence of axillary lymph node involvement and distant metastases is low.