Fine-needle aspiration cytology of low-grade cribriform cystadenocarcinoma with many psammoma bodies of the salivary gland.

Low-grade cribriform cystadenocarcinoma (LGCCC) is a rare salivary gland tumor that was recently defined as a variant of cystadenocarcinoma by the 2005 World Health Orgazniation (WHO) classification system. We report cytologic findings of an unusual case of LGCCC with many psammoma bodies. A 90-year-old man presented a palpable mass on his left parotid gland. Fine-needle aspiration (FNA) cytology showed tumor cells that were arranged in clusters and dispersed individually. The tumor cells showed mild atypia and had clear or dense cytoplasm with some vacuoles. Numerous psammoma bodies were noted. After surgical resection, the histologic examination revealed a mixed solid and cystic mass showing intraductal growth with focal stromal invasion. The S-100 protein expressed in the tumor cells, but smooth muscle actin and p63 were positive only in myoepithelial cells. Although LGCCCs resemble other salivary gland tumors, differentiating LGCCC during preoperative FNA is important to avoid unnecessary overtreatment.