DIAGNOSTIC PITFALLS OF ASPIRATION CYTOLOGY OF SALIVARY DUCT CARCINOMA

BACKGROUND. Salivary duct carcinoma (SDC) is a highly aggressive prima ry salivary gland neoplasm that resembles intraductal and infiltrating breast carcinoma histologically. The purpose of this study was to rev iew the cytologic features of histologi cally proven salivary duct car cinomas and to identify the potential pitfalls in cytologic diagnosis. METHODS. Fine-needle aspiration cytology of nine histologically prove n salivary duct carcinomas was reviewed. RESULTS. The patients' age ra nged from 62 to 89 years (median, 69 years). There were eight males an d one female. The cytologic diagnoses of these cases were as follows: pleomorphic adenoma (PA) (three cases), high grade carcinoma, not othe rwise specified (three cases), mucoepidermoid carcinoma (MEG) (two cas es), and atypical cytology with differential diagnosis including MEG, oncocytoma, and acinic cell carcinoma (one case). The spectrum of cyto logic findings included broad flat sheets and three-dimensional cluste rs. There was mild to severe cellular pleomorphism and nuclear atypia. Papillary clusters and cribriforming occasionally were identified. Bl and cytologic features and prominent hyaline stroma, shown to represen t the dense fibrosis on histologic sections, were identified in three cases cytologically interpreted as PA. CONCLUSIONS. Fine-needle aspira tion of SDC may be difficult to interpret accurately, and bland cytomo rphologic features in some cases may lead to a false-negative interpre tation; several clinically important pitfalls are demonstrated in our series. (C) 1997 American Cancer Society.