Mucoepidermoid carcinoma of the breast shares cytogenetic abnormality with mucoepidermoid carcinoma of the salivary gland: a case report with molecular analysis and review of the literature.

Mucoepidermoid carcinoma of the breast is a rare entity with specific morphologic and immunohistochemical features similar to its salivary gland counterpart. In the 28 reported cases to date, there has not been a comparison of the molecular characteristics of this tumor with salivary gland mucoepidermoid carcinomas. Herein, a case of mucoepidermoid carcinoma of the breast with a molecular alteration similar to its salivary gland counterpart is reported. A lymph node metastasis was identified despite a predominantly in situ component and foci of microinvasion. The morphologic, immunohistochemical, prognostic, and molecular features are discussed.