True malignant mixed tumors (carcinosarcoma) of salivary glands.

True malignant mixed tumors (carcinosarcomas) of salivary glands are of a high grade of malignancy and are distinguishable from the more frequently occurring carcinomas ex pleomorphic adenoma. Having a putative origin from a benign pleomorphic adenoma, the true malignant mixed tumor is an aggressive, often rapidly lethal neoplasm in which the sarcomatous element is most often a chondrosarcoma and the epithelial element is most often a ductal carcinoma. The twelve cases in this report represent the largest recorded series to date.