Sarcomatoid salivary duct carcinoma of the oral cavity.

This report recounts a new case of sarcomatoid variant of salivary duct carcinoma in a 45-year-old woman. The 1.5-cm polypoid mass protruded from the retromolar area and focally extended into the pharyngeal wall. The patient was free of disease for 11 years. The tumor showed a biphasic malignancy; nondescript sarcomatous proliferation predominated over ductal carcinoma population, with perceptible blending of the two components. The sarcomatoid areas had no heterologous properties. Discohesive pleomorphic cells were immunopositive for vimentin, epithelial membrane antigen and AE1/AE3 at a significant rate. A dual expression of AE1/AE3 and vimentin was also evident in enmeshed foci of conventional cribriform adenocarcinoma. Thus, the sarcomatoid histology represents a dedifferentiated phenotype of salivary duct carcinoma.