Abstract

A 65 year-old male patient presented with a large palpable mass beneath the areola of the right breast for 7 years. The resected breast tissue was almost totally replaced by a round large solid mass (9 6 cm) with a pink-gray to yellow firm, partly nodular cut surface. Microscopically, the tumor revealed the diagnostic biphasic cellular pattern of adenoid cystic carcinoma, which consisted of both cribriform pattern of myoepithelial cells and tubular pattern of epithelial cells. On immunohistochemistry, the tumor revealed immunoreactivities for alpha-smooth muscle actin and S-100 protein in the myoepithelial cells and for AE1/AE3 in the epithelial cells. Mitoses were scarce. Multifocal lymphatic permeation and foci of perineural invasion were also found. Underlying resection margins and overlying skin were invaded by the tumor. We diagnosed this tumor as grade II adenoid cystic carcinoma according to the system utilized for the salivary gland tumors.

• Keywords: Adenoid cystic carcinoma;Male breast