Salivary duct carcinoma. Is a specific diagnosis possible by fine needle aspiration cytology?

To review the cytomorphologic features of salivary duct carcinoma and to evaluate the likelihood of definitive diagnosis by fine needle aspiration.

The cytomorphologic features of two cases of salivary duct carcinoma, both occurring in the parotid gland in men over 80 years of age, were evaluated by fine needle aspiration and compared to cytologic features described in the literature. Additionally, previously reported diagnoses rendered by fine needle aspiration of salivary duct carcinomas were compiled from the cytology literature. The likelihood of arriving at a definitive diagnosis by fine needle aspiration was determined from the frequency of correct cytologic diagnoses reported in the literature.

The most characteristic features of salivary duct carcinoma by fine needle aspiration appear to be flat sheets with a cribriform pattern and tumor cells in a necrotic background with pleomorphic, eccentric nuclei and granular cytoplasm. However, no definitive diagnoses of salivary duct carcinoma by fine needle aspiration have been recorded in the cytology literature.

Because of the morphologic spectrum displayed by this tumor and the absence of definitive cytologic diagnoses in the literature to date, it is unclear whether a diagnosis of salivary duct carcinoma can be rendered by fine needle aspiration. Nevertheless, if cribriform groups are noted in a salivary gland aspirate, the diagnosis of salivary duct carcinoma should at least be considered.