ADENOID CYSTIC CARCINOMA OF THE BREAST - DIAGNOSIS BY FINE-NEEDLE ASPIRATION

Adenoid cystic carcinoma rarely occurs as a primary breast malignancy. When seen in fine-needle aspiration (FNA) material, it is identical t o its counterpart in the salivary glands. We report six cases diagnose d by aspiration in patients aged 32-82 yr. The smears were highly cell ular and featured extracellular spheres of metachromatic material. The se were surrounded by small, uniform cells with bland nuclei and very little cytoplasm. Numerous similar cells occurred singly in the backgr ound The cytologic differential diagnosis of adenoid cystic carcinoma includes other entities that produce extracellular metachromatic spher es including collagenous spherulosis. We describe and illustrate simil ar material originating in inspissated secretions or stromal fragments from fibrocystic change and fibroadenoma, as well as infiltrating duc tal carcinoma. Diagnostic criteria for adenoid cystic carcinoma and th e clinical relevance of distinguishing this rare tumor from typical in filtrating ductal carcinoma are discussed.