Mucoepidermoid carcinoma of the breast.

Five cases of mucoepidermoid carcinoma (MEC) of the breast are reported. All patients were women ranging in age from 29 years to 80 years. As histological grading is one of the most important prognostic factors in breast invasive carcinomas, MEC was graded using the Auclair et al. [1] grading system specific for MEC of salivary glands and the Elston and Ellis [4] grading method, a widely employed grading system in breast cancer. It was found that the two different grading systems appear to be interchangeable in assessing the grade of MEC of the breast. Accordingly, three cases were regarded low grade (G. 1), one intermediate (G. 2) and one high grade (G. 3). The cases were studied with immunohistochemistry and were found to have the same keratin pattern shown by their salivary gland counterpart. It was found that there are more similarities than differences between MEC of the breast and of salivary glands.