Abstract
A rare case of Carcinoma in pleomorphic adenoma arising in the left tongue margin in an 88-year-old Japanese woman is reported. Histologically, most of the lesion showed undifferentiated carcinoma composed of clear cells and moderately or poorly differentiated squamous cell carcinoma, with a small area of pleomorphic adenoma. The small number of tumor cells showed a positive immunoreaction for S-100 protein and pan-keratin. From these histological and immunohistochemical findings, the lesion was diagnosed as carcinoma in pleomorphic adenoma.
