Fine-needle aspiration cytology of polymorphous low-grade adenocarcinoma of the tongue.

The cytologic features derived from a fine-needle aspiration of polymorphous low-grade adenocarcinoma (PLGA) of the base of the tongue are described. The tumor cells were composed of cuboidal epithelial cells and short, spindle-shaped myoepithelial-like cells, and they formed large cell clusters. In the central portion of the clusters, myxoid materials were present, and palisading tumor cells occasionally surrounded them. Histological examination revealed solid proliferation of the epithelial cuboidal and spindle cells. The former frequently formed tubular and papillary structures. The tumor was not encapsulated, and invasion of adjacent muscle tissue was noted. Although the cytologic differentiation from cellular variants of pleomorphic adenoma and myoepithelioma is difficult, the feature of palisading tumor cells may be useful in the differential diagnosis.