Carcinoma arising in a benign lymphoepithelial lesion.

A rare case of carcinoma arising in a benign lymphoepithelial lesion of the parotid gland is reported and compared with seven previously reported cases. The carcinomas were poorly differentiated squamous cell carcinoma in two cases, acinic cell carcinoma in one case, and undifferentiated carcinoma in five cases. This group of tumors differs from undifferentiated carcinoma with lymphocytic infiltration in their association with a benign lymphoepithelial lesion. There has been no distinct racial or geographic distribution noted.