Clinicopathological characteristics of adenoid cystic carcinoma of the breast: an analysis of 3 cases

Objective To explore the clinicopathological features and diagnosis of adenoid cystic carcinoma of the breast (ACCB) . Methods Clinical data of 3 cases of ACCB were collected and followed up to observe the clinical pathological features. Immunohistochemistry was used to determine the immune phenotype. Results All the 3 cases were female, aging from 55 to 72 years old (61 years old as the average) . The tumors were found in subareolar region well-circumscribed. ACCB was characterized by the presence of a dual cell population of luminal and basaloid cells arranged in cribriform and tubular-trabecular patterns. On immunohistochemical staining, the myoepithelial cells expressed SMA, CK5/6, P63, CD117 and the glandular epithelium cells were mostly positive for CK18, EMA, CK7, while no expression of ER, PR, HER-2, CD10 was observed. Conclusions ACCB is a rare neoplasm with a triple-negative, basal-like phenotype, but exhibits an indolent clinical behavior. The diagnosis can be worked out by evaluation of clinical characterstics, histological and immunohistochemical features. Key words: Breast; Adenoid cystic carcinoma; Clinical pathology; Immunohistochemisty